fluffy weed

Why can’t I grow dense buds?

Bud density isn’t everything… but it sure is nice! If your buds keep coming out light and fluffy and you’re not sure why, this article will break it down for you. Learn exactly how to get the densest cannabis buds possible.

Example of dense buds

Learn how to prevent airy “popcorn” buds!

Here are the 5 most common reasons your buds aren’t as compact as they could be.

1. ) Genetics

You can’t overcome a plant’s genes. Some plants will only grow small and airy buds, even in perfect conditions. If the genetics don’t support bud density, it’s not your fault if buds come out fluffy, and there’s not much you can do. That being said, some of my absolute favorite strains have buds that tend to come out with a lower density. Low density doesn’t necessarily mean buds are bad. It’s common with sativa and haze-leaning strains, as well as certain hybrids.

Once you’re smoking the buds, you don’t notice the difference!

I personally love Durban Poison for the captivating bud effects and excellent yields, but the buds aren’t necessarily the most dense.

Same thing with Liberty Haze, another favorite of mine. High yields and potency, but a somewhat looser bud structure.

Choosing a strain that’s known to grow dense will considerably increase the chance of producing dense buds. Indica-leaning strains tend to develop the densest buds, though these days, just about every strain is a hybrid.

Aurora Indica is a hardy strain that stays short and tends to grow solid buds even in poor conditions (plus the yields and effects are fantastic)

These are the rock-hard buds from that Aurora Indica plant

Bubblelicious is another popular strain that produces dense buds with splendid effects

Here are more dense strain recommendations:

  • Original Amnesia – The effects more than live up to the name (you won’t remember what you’re doing). I’ve grown this strain a few times, and buds alway come out dense and tight!
  • Bubba Kush – One of the densest versions of the classic strain, and outstanding effects!
  • L.A. Sorbet – A lovely cross with the effects of L.A. Confidential but sweeter flavors and even denser nugs.
  • Critical Purple Kush – Purple strain with strong body effects. Buds leave you relaxed and happy.
  • Somango – Although the buds have strong, psychoactive Sativa-like effects, the plant grows dense buds and has a relatively short flowering period just like an Indica.
  • Wonder Woman – Not only does this strain produce rock-hard buds, but it’s also one of the highest yielding strains I’ve ever grown. It always yields more than any other plant in the tent.
  • Pink Kush – Beautiful dense buds with exceptional effects. Superb bag appeal.
  • Black Sugar – Stays short, high yields, and dense sparkly buds!
  • Power Africa x MK Ultra FAST – Great for outdoors, mold-resistant, and ready to harvest earlier than most strains.
  • Cinderella Jack auto – Most dense (and potent) autoflowering strain I’ve grown so far!

What’s your favorite dense strain? Let us know!

2.) Poor Nutrition in the Flowering Stage

Cannabis plants tend to be relatively forgiving in the vegetative stage, and the exact nutrients provided don’t matter much as long as plants are growing green and healthy. Yet once you’re in the flowering stage and buds are forming, nutrients begin to have a direct effect on your bud quality, density, and yields.

Don’t Let Plants Run Out of Nutrients While Buds Form

Don’t rely on regular potting soil for nutrients in the flowering stage. Plants that are grown in the same soil from seed to harvest often use up the nutrients by the time buds start forming. Proper nutrition is crucial for a plant to produce the biggest, densest buds.

Don’t rely on regular potting soil to provide nutrients while buds are forming. Plants need plenty of P&K in the flowering stage.

If you’re already adding cannabis-friendly nutrients in the water, this likely doesn’t apply to you.

However, if you’re not using nutrients, It’s a good idea to supplement your plant with flowering stage nutrients (high in P and K). The exception is when you’re either regularly transplanting into fresh soil, or using a composted, amended soil (which slowly releases organic nutrients throughout the plant’s life). The specific brand of nutrients isn’t nearly as critical as making sure you’re giving the plant what it needs. Learn more about the best cannabis nutrients.

Get quality nutrients to make sure your plants get enough nutrients in the flowering stage

Avoid Too Much Nitrogen in the Flowering Stage

On the flip side, you can give plants too high levels of nutrients. Providing high levels of nutrients overall causes nutrient burn, which is cosmetic and doesn’t have a massive effect on bud density. However, if you’re giving plants too high levels of nitrogen (N) in the flowering stage, it can inhibit bud development.

Too much nitrogen (N) causes dark green leaves. Sometimes they appear almost shiny

A nitrogen toxicity sometimes causes the tips of leaves to claw down

Luckily it’s effortless to tell if your plant has too much nitrogen. The main symptom of a nitrogen toxicity is dark green leaves, and possibly also clawed tips.

Too much nitrogen in the flowering stage can suppress bud development

A nitrogen toxicity is super easy to fix. Just reduce the amount of nitrogen your plants are getting. Don’t stop giving nitrogen altogether though, pull it back.

If you’re using all-purpose or vegetative nutrients (which are high in nitrogen), you need to find different nutrients. Suitable nutrients for the flowering stage are typically labeled as “Bloom” nutrients and contain low levels of Nitrogen. If you’re using nutrients with multiple bottles that you combine according to a nutrient schedule (like the General Hydroponics Flora trio or the Fox Farm trio), you don’t need to worry. The schedule will automatically decrease the amount of Nitrogen during the flowering stage.

Buds don’t develop as well as they could when a plant is getting too much nitrogen

What if you’re using Bloom nutrients with low nitrogen, but plants still look dark?

In this case, reduce the nutrient levels overall. Don’t change the ratio. You can use fractions to figure out how much nutrients to add (for example trying to cut the nutrients by a 1/3), but I don’t like doing fractions. It’s too easy for me to mess up! Instead, I add extra water after mixing nutrients to dilute the overall levels without messing with the proportions.

When treating a Nitrogen Toxicity, make sure that you give enough water to get some runoff. Runoff water helps flush out any nutrient buildup in the grow medium.

Don’t Ignore Nutrient Deficiencies

Now you know that flowering cannabis plants need plenty of Phosphorus and Potassium (P&K), but not much Nitrogen (N). The next most common nutrient challenge in the flowering stage is the appearance of nutrient deficiencies. If you’re not adding nutrients in the water, there’s a chance that the plant needs higher levels of nutrients overall, and supplementing with a suitable Bloom nutrient will solve the problem.

Not sure which bloom nutrient to get? Dyna-Gro Bloom is an affordable and effective bloom nutrient for cannabis in any grow medium that will provide your plant with complete flowering stage nutrition in any grow medium. An easy way to prevent flowering stage deficiencies!

However, if you’re already using nutrients and still see a nutrient deficiency, it’s likely caused by incorrect pH at the roots.

Don’t ignore nutrient problems like this potassium deficiency! Keep plant leaves as healthy as possible in the flowering stage for the best bud development.

Why should you care about nutrient deficiencies?

Although P&K are most important to bud development, your plants need a variety of nutrients to complete normal plant processes. Any time you ignore a plant that’s getting sick, you’re lowering the overall growth rates and potentially reducing bud size and density.

What About Supplements?

What about plant supplements? How important are they to bud density?

The truth is, you can achieve incredible bud quality and density using just base nutrients. They contain everything your plant needs for healthy growth, and so you don’t need any supplements to grow great buds. When I first started growing, I felt confused because it seemed like you need supplements to produce brag-worthy buds and yields. I’ve learned over the years that nutrient companies want you to believe that because that helps them sell more bottles. I’m not saying that supplements don’t provide benefits, I just want to assure you that they’re not necessary. They can sometimes make things more complicated by interacting with your nutrients or each other. Many supplements can be useful in small doses but may kill your plants at higher doses, so give sparingly at first to see what effect they have.

Some supplements claim to increase the density of buds, but it’s hard to pin down exactly which ones work. Unfortunately, there are not many side-by-side experiments showing the difference that each supplement makes. Here are some popular choices.

These supplements claim to increase yields and density with extra Phosphorus (P) & Potassium (K)

  • Liquid Koolbloom (by General Hydroponics)
  • Hydroplex (by Botanicare)
  • Beastie Bloomz (by Fox Farms)

Tips for using supplements in the flowering stage

  • Only add one new supplement at a time. You’re most likely to have unexpected results if you add several new things at once.
  • Adding just one supplement at a time also helps you pinpoint which supplement is causing the effects you see.
  • Always use supplements made by the same company as your base nutrients. Sticking with one company reduces the chance of unwanted interactions. Each company designs its nutrients and supplements to be used together.
  • Use any supplement sparingly. A little usually goes a long way! Too much of certain supplements can harm plants, burn the leaves, or stunt bud growth. Always start at the lowest recommended dose (or less) and only increase if plants seem to be responding well.

We all want magic in a bottle, but it’s important to remember that the environment and overall plant care are much more critical to achieving excellent bud quality and yields than any particular supplement. You can’t overcome a bad growing environment no matter what you give your plants (more on that next).

3.) Wrong grow light

Unfortunately, some grow lights struggle to grow dense buds no matter what you do.

Grow lights that excel at producing excellent bud density:

Fluorescent lights like CFLs and T5s can produce dense buds when you keep the lights close. However, the lower buds on plants grown under fluorescents are typically on the fluffier side because the light doesn’t penetrate far into the plant. Fluorescent lights produce high bud quality and potency (I’ with CFLs), but if density is most important to you, fluorescent lights may not be the best choice.

CFLs and T5s must be kept extremely close to achieve high bud density. Only the buds close to the light will get dense.

Specific LEDs (especially the no-name ones) have low penetration down into the plant and buds simply don’t harden up.

Low-quality LEDs often produce airy buds. These buds were grown under cheap LEDs. They stayed small and larfy even though plants looked happy and healthy.

If density is the most crucial factor for you, generally, you’ll get the best results with HID lights like HPS in the flowering stage. However, the technology for LEDs has improved dramatically in the last few years, and there are many modern models of LEDs that consistently produce long, dense buds.

High-quality LEDs tend to cost a bit more, but the results can be worth it. For example, you can achieve impressive density and yields from LED models like the HLG Quantum Boards (HLG 100 3000k version, HLG 300 V2 R-spec, HLG 550 V2 R-Spec, etc.). Learn more about the best LED grow lights for cannabis.

Certain LEDs produce high density. The HLG 100 (3000k version) uses only 100W and made these extremely dense buds for me. I’m currently flowering several plants under an HLG 300, and so far, I’m even more impressed!

HPS grow lights consistently produce dense buds as long as plants are healthy and the environment is right

This bud was grown under HPS

Buds become solid even with low-wattage models like this 150W HPS.

LEC/CMH grow lights also tend to produce dense buds (though often not as dense as HPS). One of my favorite aspects of growing with an LEC is buds come out extremely sparkly and stinky compared to other grow lights.

These sticky, dense buds were grown under a 315 LEC.

4.) Vegetative Stage Mistakes

During the vegetative stage, you have total control over a plant’s final shape and size. You can use this to your advantage. Set your plants up correctly so they can support dense buds later.

Too Many Bud Sites

You can increase your overall yields by training your plant in the vegetative stage (with techniques like LST or manifolding), so it grows multiple primary buds instead of one.

Plant training increases yields by forcing plants to grow multiple main buds instead of just one

However, if you grow a plant with tons and tons of buds sites, it may not be able to fatten them all up before harvest. This is most likely to happen on smaller plants, younger plants, and when using smaller grow lights. If you’ve got a relatively small plant, try to force the plant to focus on just a few main buds instead of dozens. A general rule of thumb is that plants under 2 feet tall should have 4-10 primary buds. Big or wide plants can support more.

Don’t spread the plant’s energy too thin or you may end up with tons of baby “popcorn” buds.

This plant has too many bud sites for its size. Although it may get good yields, none of the buds will grow particularly big or dense.

Bigger plants, older plants, and manifolded plants can support more big, dense buds. Especially when combined with a powerful grow light!

Don’t Switch to Flowering Stage Too Early

This is sort of related to the last point. Bigger plants can support bigger buds, and switching to 12/12 early means that your plant might not get big enough to make dense, thick colas/buds.

Try to switch to the flowering stage when your plant has reached about half the final desired size. Since plants about double in size after they start getting 12/12, this should give you the biggest plants possible for your grow space.

Switch to 12/12 when plants are half the final desired height. This helps ensure they’re big enough to support dense buds

5.) Flowering Stage Mistakes

A common cause of airy buds is poor care in the flowering stage. Here are several factors that can prevent you from getting the best density. This stage is the most essential part of your plant’s life when it comes to bud quality, density, and yields!

Ultra-leafy plants

When plants are so leafy that air and light can’t get through the plant, the buds don’t get as dense as they could.

These plants are too leafy for the flowering stage. Buds won’t fatten far into the plant, and won’t be as dense as they could be.

Air and light should be able to travel through the plant in the flowering stage. For some plants, you won’t have to do anything. But with some plants, you may need to remove leaves to achieve the optimal amount of leafiness.

You may need to remove leaves if plants get too leafy

Not sure if your plants are too leafy?

This 3-step defoliation tutorial ensures your plants have the perfect amount of leaves.

Don’t ignore pests or disease

I mentioned nutrient deficiencies already, but it’s also vital that you react immediately to any other issues that may come up. Don’t ignore a problem until it gets out of control.

Typically a plant is simple to treat when it’s just starting to experience problems, but the longer it goes on, the worse it gets. An unhealthy plant won’t grow buds as well as a healthy one, so stay on top of your plant’s health.

Don’t ignore problems like pests or disease

Extreme temperatures (especially heat)

A lot of growers ignore issues with the plant’s flowering stage environment. Growers often don’t realize how much this can hurt their results. It’s easy to ignore environmental problems like heat because typically, your plants and buds will still be growing.

If plants look okay, the heat should be fine, right? Unfortunately, no.

When the air is too warm (above 80°F/26°C) in the flowering stage, buds tend to grow more light and airy. Sometimes buds even grow unsightly foxtails as a result of heat.

Buds get less dense when it’s too hot. Look at the loose structure of this bud grown in extreme heat.

Too-cold air can also cause buds to grow small, airy, and loose

Another thing about temperature: cannabis plants in the flowering stage like it to be a little warm in the day, but cool at night. Warm nights are also associated with airy buds. Try to keep the temperature between 65-80F (18-27C) for the best bud development in the flowering stage.

High Humidity

Humidity in the flowering stage is another factor that’s often ignored. Each plant leaf is constantly adding moisture in the air, which means that the humidity tends to rise in the grow space as plants get bigger. That’s ironic because plants like high humidity when they’re young/small, but it causes problems in the flowering stage.

High humidity can trigger bud rot and powdery white mildew, which is plenty enough reason to control humidity. But there’s more. Buds don’t get as sparkly as they could in high humidity, and buds overall tend to grow more loose and airy.

Keep humidity under 50% RH while buds are forming for the best results!

Keep humidity under 50% RH while buds are forming, or they may not get as dense as they could

Poor Airflow

Buds seem to fatten the best when they get plenty of light and fresh air. You’ve already taken care of light, but you should also ensure your plants get excellent airflow. Air circulation helps control humidity, prevent wet spots, and moves air through the plant and around the buds.

Make sure plants get fresh air and good airflow

Any other major stress

If your plant doesn’t “look good” or seems sickly in the flowering stage, that’s the first thing you should focus on to improve the density.

If plants look generally unhealthy, focus on fixing that before trying anything else. These plants are suffering from heat stress. Look how loose the buds are.

Buds tend to stay small and fluffy on an unhealthy plant.

6.) Harvest Mistakes

Don’t harvest too early

Buds gain a lot of size, weight, and density during the last few weeks before harvest time. That means if you harvest your plants a few weeks early, they will be significantly smaller and less dense than they could be. Early-harvested buds also aren’t as potent and may give some people a headache. There are lots of great reasons to harvest your plants at the right time.

Don’t harvest until plants are ready. These Original Amnesia buds are dense and ready to harvest!

Not drying and curing

Drying and curing buds makes them smoke better, smell better, feel more potent. Don’t skip this step!

As a bonus, drying and curing can help tighten buds up for that “California dispensary” look.

Buds tend to look more “tight” and feel denser after being dried and cured

I’ve found that waiting to trim buds until after drying can also help them feel and appear more dense (compared to trimming before drying)

If you avoid these mistakes, you will produce cannabis buds as dense as you’ve always dreamed!

Why can’t I grow dense buds? Bud density isn’t everything… but it sure is nice! If your buds keep coming out light and fluffy and you’re not sure why, this article will break it down for you.

How To Grow Dense Cannabis Buds

Say “No” to Small, Airy Buds!

Grow Fat, Dense Cannabis Buds!

Top 5 Most Common Reasons for Airy Marijuana Buds
(get a complete breakdown of all the ways to increase bud density in the article below)

Light – The most common reason buds don’t develop as densely as they could is the plant didn’t get enough light in the flowering stage. Although cannabis can survive in relatively low light levels, it won’t produce much bud. Up to a point, more light in the flowering stage = bigger buds. On the flip side, too-bright light (less common, but can happen when buds are too close to grow lights) can also cause buds to develop poorly and/or produce airy, hairy fox-tails.

Strain / Genetics – Some strains will only produce airy buds no matter what you do. For example Sativa plants often grow buds that are less dense, while Indica buds tend to grow more compact. Although one style isn’t necessarily better than the other, if you want dense buds it’s important to start with genetics that come from a plant that grows dense buds.

Temperature – Cannabis wants the temperature just right for optimal bud growth, which is about the same temperature as what’s comfortable for humans. Too hot temps in the flowering stage (especially above 85°F/30°C) can cause plants to develop loose buds, and can also cause buds to herm and become seedy.

Nutrients – Buds won’t fatten and get dense unless they’re getting the right nutrients at the right time, which means low Nitrogen (N) and plenty of Phosphorus (P) and Potassium (K) in the flowering stage. Giving too much Nitrogen (found in all-purpose plant food) in the flowering stage results in smaller, looser buds. Learn more about nutrient ratios. Other nutrient problems and deficiencies can also negatively affect your bud development if left unchecked. However, the most common reason growers see nutrient problems hurt development in the flowering stage is incorrect pH at the plant roots.

Airflow & Bud Spacing – Poor airflow around buds and lack of strong, direct light will prevent those buds from developing as densely as they could. Buds need a little space to themselves in order to get big and dense, and won’t fatten up if they’re not directly exposed to fresh air and strong light. In the wild cannabis is a wind-pollinated plant, so it only spends energy growing and fattening buds that are exposed to a breeze and the sun. To make sure the buds are getting a breeze, each big cola on your plant should have a few inches of space around it that it’s not sharing with leaves or other buds.

Never grow loose, airy buds again!

6 More Tactics to Increase Bud Density
In addition to fixing the problems stated above, here’s a complete breakdown of additional tactics to increase bud density (more complete info in the article below or click the links)

Reduce humidity below 45% RH during last 2-3 weeks before harvest – Lowering the humidity towards the end of the flowering stage triggers a natural plant response that can make buds more dense as well as increase resin production

Density Boosting Supplements – There are two main classes of bloom-boosters. The first class focuses on enhancing plant processes, and uses dozens of various ingredients like amino acids and trace minerals. The second class works by increasing Phosphorus/Potassium levels directly. Some growers also use Blackstrap molasses in order to accomplish many of the same goals without needing a special plant supplement.

Don’t harvest too early! Harvesting too early will prevent your buds from finishing up. They gain a lot of weight and density during the last few weeks before harvest, and you’re hindering all your hard work by not waiting just a little longer.

Dry & Cure Your Buds – In addition to improving taste, smell and potency, drying and curing your buds the right way will cause them to “tighten up” a bit. If you dry your buds too quickly or don’t cure them in glass jars, you’re missing out on almost 50% of what’s going to determine your final bud quality!

Don’t overwater your plants – it’s boring but true! Not much to say about this, but don’t overlook this common issue and make sure to water your plants right. If your plants leaves are droopy, it means you could be missing out on better growth!

Get a Big Enough Container – If your container is too small your plant just won’t be able to support bigger, denser buds no matter what else you do. Make sure to get the right size container and if possible, get a “smart pot” or “air pot” as they prevent overwatering, increase growth and support larger plants!

Continue reading to learn more in depth about these tactics and techniques to boost buds density!

How to Grow Dense Cannabis Buds Every Time

1.) Provide enough light (but not too much)

Bright but not too bright. When new growers have problems with light, it’s usually that their grow is under-powered. A few small CFLs or a tiny LED grow light that uses less than 100W is seriously underpowered even for one plant. Although plants will grow under these types of light in the vegetative stage, they’re not powerful enough to really drive bud growth in the flowering stage. Which cannabis grow light works best?

Even if the plant is healthy, buds never thicken up properly if they don’t get enough light in the flowering stage

The next most common reason growers have trouble with light levels is they keep their grow lights too close or too far away from their plants.

How far away to keep different types of lighting

MH/HPS – depends on the size of the grow light – learn how far away MH/HPS grow lights should be from your plants

Fluorescents & CFLs – keep as close as possible without hurting your plants with heat. If cool enough, these can be kept just inches away from plants. Make sure all parts of the plants are within a few inches of a fluorescent bulb for the densest buds.

LED grow lights – it’s a good idea to consult the manufacturer to learn how far away these should be from your plant because every model is different. Most LED grow lights should be kept at least 18″ (45cm) from the tops of the plants. The more powerful LEDs may need to be kept even further away to prevent bud and leaf burn in the second half of the flowering stage.

Outdoor growers should try to ensure that plants get 8+ hours of direct sunlight every day, but you may want to protect plants with a screen on scorching hot days.

CFL grow lights should be kept as close to buds as possible as long as heat is under control. If they’re kept more than a few inches away from the buds, like these ones, the buds will never fatten up or become dense

On the flip side, LED grow lights are commonly kept too close, which burns your buds in the late flowering stage and may cause bleaching, hermies and/or foxtails. Most LEDs need to be kept 18″ or more away from the tops of your plants in the second half of the flowering stage

LED burnt buds (from LEDs being too close) often end up growing thin, loose and leafy

Read the full tutorial on optimal grow light distance from plants

Color spectrum – yellow/orange/red colored grow lights (like the light from HPS bulbs or “soft white” colored CFLs/fluorescents) tend to produce the densest buds. Their color mimics the reddish light from the autumn sun. However bright light in any spectrum will produce good bud as long as there’s enough brightness.

HPS lights produce intense light levels and give off a color spectrum that is ideal for big yields and very dense buds.

HPS grow lights are one of the most efficient grow lights available today as far as electricity used for density/yields produced (even more efficient than most LED grow lights). They’re actually relatively cheap to start with, they’re just the right color spectrum for optimal flowering, and they’re more standardized and intuitive to use than many other types of grow lights. Learn more about finding the right size HPS for your space

Some growers use Metal Halide and other more “blue” colored lights for the flowering stage, and still produce good results. In fact some growers prefer MH lights for budding (even though yields are lower) because they believe the light spectrum increases trichome/resin production and overall potency. There is still testing going, but the results look especially promising for CMH / LEC grow lights, a variant of MH lights that uses a ceramic arc tube (very similar to what’s used in HPS bulbs) to increase the brightness. However, even with these improvements, CMH grow lights are still significantly less bright than HPS grow lights (CMH: 90-105 lumens/watt vs HPS: 105-150 lumens/watt). Learn more.

No matter which grow lights you’re using…

  • Make sure you’re using a good reflector and reflective walls to get as much light as possible to your plants
  • Keep lights close to the top of your canopy without increasing heat to unsuitable levels or light-burning plants. Close but not too close! It’s important to find out how far your grow lights should be for optimum growth.
  • Make sure that all parts of the plant (and especially bud sites) are bathed in bright light – any buds in a shadowy part of the plant won’t become dense!

2.) Grow a strain that tends to produce dense buds

Genetics play a huge role in how your cannabis plants grow, including the appearance, smell and taste of their buds.

Indica-dominant strains tend to produce more dense buds (though not always of course). The indica-leaning buds pictured to the right are incredibly dense and were grown under intense light, but the majority of strains could never achieve this density no matter what you do as a grower. To a certain degree, density is determined by strain.

Some sativa-leaning strains tend to produce less dense buds, but also provide a cerebral “daytime” effect that many growers love. Sativa-dominant strains can still be high-yielding so you may end up with very long buds as opposed to small thick nuggets like with some indica-leaning strains.

Seeing different grows featuring a strain will help give you an idea of what the buds of that particular strain tend to look like.

Important! There are sometimes different versions of strains by different breeders. You can often find several versions of very popular strains, and each version can grow wildly different from each other and which produce different results.

“White Widow” from one breeder may be completely different that “White Widow” by another breeder. So when researching strains, always pay attention to the breeder in addition to the strain name. Learn about some trusted breeders.

How to Research a Marijuana Strain
(or read the full tutorial here)

  • Make a list of a few possible strains to grow – If you don’t already have an idea about which strain you want to grow, it helps to start by narrowing down your list of possible strains. When I’m researching for a new grow, I usually start with a big seed bank,since they give you lots of helpful information about each strains. These big seed sources usually have a “strain selector” option that lets you put in the specific features you’re looking for and get a list of results. I use Seedsman because they only carry seeds by trusted breeders.
  • Search for a grow journal with pictures of your strain during the grow process – Type “STRAIN-NAME grow” into and look at the regular results plus the Google image results. When looking at image results, it’s important to click through to the page instead of just looking at the image so you can learn more. These steps may give you good leads toward finding a grow journal featuring your strain, but not always. Remember to also pay attention to which breeder the grower got their strain from.
  • Search for the strain name on Youtube – you may possibly find people who may have grown the strain and documented their grow with video. Video is a great way to give you an idea of your strain might look like in the flowering stage, and lots of growers post full video grow journals on Youtube. Again, also pay attention to the strain breeder.
  • Seedfinder – I like the site for strain research. It is one of the best ways to find out the genealogy and ancestry of a strain by a particular breeder. It has growing reviews and pictures for some strains which is really helpful, but that can be hit or miss since many strains are missing any type of grower feedback. Some of the reviews are in German or other languages. You can translate almost any language into English by copying and pasting it here:

One last thing to keep in mind… Looks are important to many growers, and looks are part of the whole experience when using cannabis.

…But when it comes down to choosing the strain, I recommend to first choose strains that produce the effects you like as opposed to thinking only about density or looks. Some strains may not produce buds that look as dense as what you see in magazines and online, but will give you exactly the effects you are looking for.

3.) Keep temperature under 85°F (30°C)

While it isn’t always possible to control temperature, there’s a lot you can do (especially indoors) to keep temps at the optimum levels for bud development. Choosing a suitable strain for your growing environment will also make a big difference.

Cannabis plants like temps around 70-80°F (20-26°C) in the flowering stage for best development. Temps over 85°F (30°C) usually makes buds grow parts that are noticeably more airy than the same plant grown under proper temps.

  • Indica-leaning strains are better at handling cold
  • Sativa or equatorial strains are better at handling heat

Too much heat triggers heat burn, airy buds, fox-tailing and also reduces potency and smell, especially for indica-leaning strains which are less resistant to heat. High temps can also lead to seedy buds if your plant herms as a result of the stress.

This bud was exposed to high temps and never really grew more than a few calyxes and lots of sugar leaves

Fox-tailing caused by heat – the entire bud is larfy and airy

Too much heat causes thin buds and strange growth patterns

Too-cold temps (especially during first 6 weeks of flowering) are less common but can also cause airy buds that don’t ever fatten up and grow dense.

Cold temps can also keep buds from developing, like this outdoor plant grown in a cold climate

Cold temps can also cause leaves and stems to turn purple. Purple leaves can be problematic since green leaves make more energy from light. That’s why it’s a good idea to avoid letting leaves turn purple too early in the flowering process.

Although indica-leaning strains tend to be more cold-resistant and sativa-leaning strains tend to be more heat-resistant, almost all strains available today are some sort of hybrid. Instead of relying just on a strain’s classification as Indica or Sativa, it’s important to learn about the particular strain and how it reacts to heat and cold. Even more importantly, watch your plant for signs of stress!

4.) Nutrients – Use the right N-P-K ratios for the flowering stage! (but don’t go overboard)

Give your plants the right ratios of cannabis nutrients during the flowering stage (while avoiding nutrient burn). Not only does this help you avoid nutrient deficiencies, it also gives your plant the building blocks needed to make buds.

Don’t forget about pH! It can be tempting to ignore this part, but pH is also incredibly important when it comes to nutrient absorption. Managing pH properly is one of the best ways to make sure that plant has easy access to nutrients at the roots.

The N-P-K values are listed on the back of most nutrient bottles

What nutrients does a cannabis plant need in order to make dense buds? In the budding stage, make sure to provide a little Nitrogen, a lot of Potassium, and a good source of Phosphorus.

Best for cannabis flowering stage (“Bloom Nutes”):

  • A little Nitrogen (N)
  • A good source of Phosphorus (P) – definitely more than Nitrogen, and possibly more than Potassium as well
  • A lot of Potassium (K) – about double the amount of Nitrogen or more

Giving relatively low levels of Nitrogen during the flowering stage helps buds fatten up

It’s important to avoid giving too much N while plants are budding, as too much Nitrogen prevents proper bud formation and results in lower yields and airy buds. This means you should not use your vegetative or all-purpose nutrients (which are high in N) during the flowering stage!

Nutrient bottles list their nutrient levels with 3 numbers. These numbers stand for N-P-K levels. In the flowering stage, avoid giving plants too much Nitrogen (N) but make sure plants get a good source of Phosphorus (P) and Potassium (K).

Dyna-Gro “Bloom” plant food, shown below, is an example of a flowering formula that has good ratios of N-P-K for the cannabis flowering stage. Any quality cannabis nutrients designed for the flowering are formulated to give your plants exactly what’s needed to produce buds.

You can take out pretty much all of the guesswork out of nutrient ratios by using a cannabis-friendly “bloom” nutrient formula during the flowering stage.

Examples of cannabis-friendly “Bloom” NPK ratios:

  • 3-12-6
  • 4-8-7
  • 2-3-5

Note: Avoid nutrients that are labeled “Grow,” “Vegetative” or “All-Purpose” in the flowering stage! In an emergency, if you can’t find specific Bloom nutrients, get cactus nutrients as they use a similar nutrient ratio as flowering cannabis plants.

For those not using nutrients, starting with amended and composted super soil is the best way make sure plants get access to the nutrients they need at the right time. As a bonus, when starting with properly composted soil, it’s the one time you don’t need to worry about pH!

5.) Expose all buds to both high levels of light and a gentle breeze – each cola needs space to increase density to maximum levels!

The most dense and weighty buds on the plant have a few inches of space to themselves and are exposed to both bright light and airflow. Buds hidden in the plant by leaves (without access to much airflow or light) stay airy and tend to never fatten up or become dense. In fact, buds sitting in stagnant, non-moving air may stop developing completely. This is why you often see small buds on very leafy plants!

Let me show you how much a difference it makes to expose buds to bright light and air. This example used defoliation. Defoliation means removing leaves, and is an advanced technique that is not suitable for beginners. Defoliation should only be used on very leafy, healthy plants that are under bright lights.

For those worried about taking off too much, similar results can be obtained much more safely simply by tucking leaves to expose bud sites.

Here’s a leafy, healthy plant which is being grown under bright grow lights – notice how many bud sites are hidden in the middle of the plant. You cant even see them all!

Here’s the plant immediately after tucking and removing leaves – notice that the buds are now much more exposed to air

Less than 2 weeks later (and after another defoliation session)

The biggest colas are the ones that get exposed to the most light and air. This may happen because cannabis plants are wind-pollinated in nature. Buds that aren’t exposed to air can never be pollinated in the wild, so the plants may “give up” on them. Yet when buds are exposed to light and air, the plant “knows” they can possibly be pollinated by the wind and so the plant puts energy toward fattening them up. Hidden buds don’t fatten up, so give your buds room and expose them to a gentle breeze!

For the most dense buds, make sure each cola has a few inches of space to itself while developing

One easy way to accomplish this growth pattern is to use the manifolding technique while the plant is still young. This spreads the plant out while producing many well-spaced colas.

6.) Lower humidity below 45% RH during last 2-3 weeks before harvest

Keep humidity under 45% in the flowering stage (especially in the last 2-3 weeks before harvest) to trigger your plant’s natural response to go into bud production overdrive. Very low relative humidity in late flower may enhance density levels, promote resin production, produce more of a smell/taste, and possibly even increase potency. Lower humidity will also prevent bud rot from forming in the middle of dense buds.

Indoor growers have a lot of options for controlling humidity in the grow space.

Outdoors, it’s best to find a strain that is suitable to growing in your climate, and give plants cover when you know there’s going to be bad weather coming soon. Protect buds from getting too wet in rainy weather, and if at all possible try to plant them in a place where they will get some amount of wind.

Lower humidity during the last few weeks before harvest can boost resin production and bud density

7.) Use Density Boosting Supplements

Before thinking about supplements, it’s most important to making sure you’re first providing the right base nutrients. Without proper base nutrients, your plant simply won’t grow or produce buds no matter what supplements you provide. So get your base nutrients first. But once you know you’re giving your plants the essentials, what do you add next?

Some cannabis supplements claim to increase yields and bud density, and generally these supplements contain a source of sugar. They also often contain ingredients such as amino acids, humic acids, vitamins, trace minerals and other additives which may be helpful to bud formation. There is another common “formula” for bloom boosters that adds a lot of extra Phosphorus and Potassium.

Give 1/2 tsp per gallon of Blackstrap Molasses when watering (for soil or coco coir) for the last 2-3 weeks before harvest to possibly increase density as well as improve taste/smell of buds

As a cheap alternative to expensive bloom boosting supplements, some growers water plants with a small amount of blackstrap molasses for the last few weeks or so before to help buds get bigger/more dense (it’s just the regular stuff you find in your kitchen or at the grocery store). It adds sugar as well as amino acids and various trace minerals. As a bonus, molasses can also improve the taste/smell of your buds. However, anything organic like molasses is not suitable for a hydroponic reservoir! Only for soil and coco growers 🙂

The jury is still out and which is the most effective supplement, but many growers are happy with bloom promoting supplements that include sources of…

  • carbohydrates/sugar
  • amino acids
  • humic acids
  • vitamins
  • trace minerals

I personally don’t use this type of supplement so I can’t recommend a particular one, but some of the most popular cannabis supplements based on this type of formula include…

  • Floralicious Plus (by General Hydroponics)
  • Liquid Karma (by Botanicare)
  • Diamond Black (by General Organics)

Note: These are only for soil or coco coir! (since these supplements contain a lot of organic materials like guano and fishmeal, they are not suitable to hydroponic reservoirs)

The supplements listed above use ingredients that add only tiny amounts of base nutrients (NPK). They use other ingredients to help the plant use its resources better, or in the case of sugar, to directly plump up buds. But that’s not the ony kind of density-boosting supplement.

Density-Boosting Supplements with Extra P & K

  • Phosphorus (P) increases number of flowers
  • Potassium (K) increases weight/density of flowers

Many popular density/yield increasing supplements contain extra Phosphorus (P) and Potassium (K), sometimes with a small amount of Sulfur (S), and possibly other ingredients like amino acids, trace minerals and/or sugar.

However, it’s very important to use these types of supplements sparingly as your regular base Bloom nutrients will already contain quite a bit of P and K. Although you want to make sure your plant can get as much P and K as it can use while making buds, you don’t want to give too much or you’re just going to burn your plants and/or cause a nutrient deficiency (too much of one nutrient can cause deficiencies in others).

Suitable for Hydro, Soil or Coco – Supplements to Increase Yields/Density with extra P & K

  • Liquid Koolbloom (by General Hydroponics)
  • Hydroplex (by Botanicare)
  • Beastie Bloomz (by Fox Farms)

8.) Don’t harvest too early!

When you harvest at the right time, you’re giving your buds the time they need to develop to their fullest. Harvesting too early will lower your yields and you’ll usually end up with more airy and less developed buds. Even worse, harvesting too early causes reduced potency and some people may get headaches from early-harvested buds.

Don’t harvest while pistils are still white and sticking out

Wait until buds are mature and have thickened up!

These buds were harvested at the right time, giving them the chance to thicken and tighten up as much as possible.

9.) Dry & Cure Your Buds

Proper drying and curing after harvest can help buds become slightly more dense, while also adding to better taste, smell, potency and bag appeal.

A proper dry/cure can help “tighten up” buds

10.) Don’t overwater your plants – it’s boring but true!

This may seem like a boring one, but just a few simple precautions can make your plant grow faster and produce bigger yields. If you want to get the most dense bud possibles, you want to cover all your bases.

So if your plant looks droopy all the time, chances are it’s hurting your yields even if otherwise your plant looks healthy!

Roots “breathe” oxygen, so good root health involves giving just the right amount of water while maximizing the amount of oxygen available to the roots with air pockets. When the roots aren’t getting enough oxygen, the plant can’t properly get water or use nutrients. As a result of unhappy roots, leaves may show signs of drooping or nutrient deficiencies, and buds stop developing.

So it’s important to water plants properly and take good care of roots for dense buds!

11.) Get a Big Enough Container & use a “Smart Pot” or “Air Pot” If Possible

The type and size of the containers you use for growing cannabis determine how big your plant can get and ultimately how much bud it can support. Smaller containers can only support smaller plants, and small plants can only grow relatively small buds. So when growng cannabis, it’s important to get a container that’s big enough to support the size plant you want.

Some types of containers such as smart pots (and air pots) actually make your plant grow faster! A smart pot is a fabric pot that lets plant roots get air from the sides, causing faster growth, while an air pot is a plastic pot with holes in the side. They also prevent plants from becoming root-bound from a too small container. Learn more about smart pots & air pots!

Get “smart pots” or “air pots” (containers that let air in from the side) to prevent plants from becoming rootbound so plants plants can get bigger than they would in a regular plant container. These types of pots also cause plants to grow faster!

In the end, density is definitely not the only thing to consider when deciding the quality of buds. There can be times when buds are too dense (which increases the chances of mold and bud rot) and there are also several strains that produce less dense buds which have amazing effects. In my opinion, an ounce is an ounce is an ounce. If you harvest an ounce of airy buds with great effects, to me that’s just as good as an ounce of dense buds with great effects, so enjoy what you grow while striving for better!

Review: How to Grow Dense Buds!

1.) Provide the right amount of light

Not enough light is the most common reason buds don’t develop as dense as they could. On the flip side, too-bright light (or buds being too close to grow lights) can also cause buds to develop poorly and/or produce airy fox-tails.

2.) Start with a strain that tends to grow dense buds

Start with the right strain to grow buds the way you want. Some strains won’t grow tight, dense buds no matter what you do.

Indica-leaning strains tend to have more dense buds, but it’s a good idea to always research a strain before growing it.

One strain that reliably produces dense buds and good yields is Moby Dick by Dinafem. This hybrid strain is popular because although the buds have strong, psychoactive Sativa-like effects, the plant grows dense buds and has a relatively short flowering period just like an Indica.

3.) Control temperature

Cannabis wants the temperature just right for optimal bud growth. Too-hot or too-cold temps can cause buds to grow airy.

Start with a thermometer! (this one also measures humidity)

Cannabis like temps around 70-80°F (20-26°C) in the flowering stage for best development.

  • Indica-leaning strains are better and handling cold
  • Sativa or equatorial strains are better at handling heat

4.) Cannabis Nutrients

Buds won’t fatten and get dense if the base nutrients aren’t right. Nutrient problems can be caused by incorrect pH, not giving enough nutrients, giving too much nutrients, or by giving the plant the wrong kind of nutrients in the flowering stage.

5.) Expose all buds to both light and a gentle breeze

Poor airflow around buds will prevent those buds from developing as dense as they could. In the wild cannabis is a wind-pollinated plant, and it only spends energy growing and fattening buds that are exposed to fresh air with a gentle breeze.

So make sure your buds are getting exposed to airflow. A small circulating fan works great to add more air movement to the grow space.

6.) Take care of roots

Under-watering, overwatering, and/or root problems (such as root rot or a too-small container) will hurt yields and prevent buds from getting as dense as they could be since the plant isn’t able to run at peak efficiency.

Roots “breathe” oxygen, so good root health involves giving just the right amount of water while maximizing the amount of oxygen available to the roots with air pockets.

So it’s important to water plants properly and take good care of roots for dense buds. Your plants will thank you for it.

There are also a few popular root supplements to help care for your root health:

7.) Keep Humidity Under 40% RH for Last 2-3 Weeks Before Harvest

Indoor growers have a lot of options for controlling humidity in the grow space.

Outdoors, it’s best to find a strain that is suitable to growing in your climate, and give plants cover when you know there’s going to be bad weather coming soon. Protect outdoor plants from wind in dry weather. Protect buds from getting too wet in rainy weather.

8.) Density-Boosting Cannabis Supplements

These supplements focus on enhances plant processes. I personally don’t use these types of supplements so I can’t recommend a particular one, but many growers swear by them. Some popular supplements of this type include…​

For soil or coco coir (since these supplements contain a lot of organic materials like guano and fishmeal, they are not suitable to hydroponic reservoirs)

  • Floralicious Plus (by General Hydroponics)
  • Liquid Karma (by Botanicare)
  • Diamond Black (by General Organics)

Suitable for Hydro, Soil or Coco – These supplements Increase Yields/Density with extra Phosphorus (P) & Potassium (K)

  • Liquid Koolbloom (by General Hydroponics)
  • Hydroplex (by Botanicare)
  • Beastie Bloomz (by Fox Farms)

9.) Don’t Harvest Early

When you harvest at the right time, you’re giving your buds the time they need to develop to their fullest. Harvesting too early will lower your yields and you’ll usually end up with more airy and less developed buds.

An important tool for harvesting at the right time is a magnifier to look closely at buds, like a jeweler’s loupe or (even better) a digital magnifier that displays the trichomes on a screen.

We took the above video using the Carson zOrb hooked up to a laptop. So far this seems to be the easiest accurate way to look at trichomes (and you can make the picture big so you’re not squinting through a tiny jeweler’s loupe 🙂

10.) Drying & Curing

Proper drying and curing after harvest can help buds become slightly more dense, while also adding to better taste, smell, potency and bag appeal.

Drying rack (optional) – use this if you live in a very humid climate as these help you dry buds more quickly.

Hygrometer (optional) – I like the Caliber IV Hygrometer because it easily fits inside quart mason jars

Humidipaks (optional) – Boveda Medium 62% packs are cheap and specifically formulated for storing cannabis so it does not dry out or get crispy

11.) Get a Big Enough Container

If your container is too small, your plant won’t be able to support big, dense buds. By choosing the right container size, you’ll help maximize your plant’s potential!

Discover the top 5 reasons buds become loose or airy, then learn how you can produce dense buds every time!