making compost tea for cannabis

Here’s How to Make Compost Tea for Your Marijuana Garden

With legal changes sweeping the U.S. as states do a U-turn on their cannabis laws, there has been a rise in the number of cannabis enthusiasts growing their marijuana at home. We love a good do-it-yourself, and today we are bringing you just the thing you need to help your crops thrive all year round!

If you have ever tried to grow your cannabis, then you will know that many strains out there need some extra special TLC to help them thrive. Compost tea is the current growing trend for cannabis cultivators, and the past twenty years have seen more and more people opting for an organic nutritional booster for their plants.

With a wealth of information out there on compost tea, it can be pretty overwhelming, especially if you have never grown cannabis before. So today we are going to be telling you why you should consider compost tea for your cannabis garden, and how you can brew your very own batch at home!

What is Compost Tea and Why Should You Be Using it for Your Cannabis Garden?

There are many types of compost tea out there, with the popularity of this elixir growing rapidly in recent years we have seen some pretty inventive versions of the mixture. Put simply though, compost tea is the act of steeping and brewing compost in water to make a liquid ‘tea’ solution.

But why bother? The benefits of compost tea are threefold: A well-brewed mixture can improve the resilience of your cannabis plant by providing it with helpful bacteria, introduce vital nutrients for healthy growth and larger yields, and improve the plant’s nutrient absorption.

You can use compost tea in many ways, and the way you make your mixture will differ depending on the type of solution you are aiming for, i.e., bacterial or fungal tea. However, that being said, the vast majority of teas will consist of an amalgamation of similar ingredients that tend to crop up time and time again.

Once you are happy with your compost tea, you can use it as a root drench to provide the soil with much-needed nutrients and to introduce aerobic microorganisms to the plant’s roots. Alternatively, you can use the compost tea as a foliar spray, which can be applied to the plant’s leaves for beneficial bacteria and to help strengthen the plant against possible diseases .

Your simplest version of compost tea may consist simply of just compost and water which has been steeped and left to brew for a couple of hours. However, experienced cannabis cultivators will tell you that for the best results you want to be getting those added extras in there.

There are hundreds of store-bought brands of compost tea out there, many of which offer different variations on key ingredients, but making your own from home can be just as simple as picking it up at the shops, and much more cost-friendly!

What Do You Need to Make Compost Tea?

This is where things can become confusing, as we have touched already on the fact that there are so many variations of compost tea – it can be hard to know where to begin! That being said, knowing and understanding the very core ingredients will help you get a grip on things, and from there you can experiment with different additional ingredients if you wish to.

At the base of any compost tea is, well, compost! We would always recommend that anyone serious about cultivation have their compost bin, which can take years to establish but is super easy and very environmentally friendly ! A good quality, healthy compost is necessary for compost tea, so if you are making your own ensure there is a good balance of greenery and brown items to supply it with the optimal level of nutrients.

If you don’t have your source of compost, or yours isn’t ready for use yet – you can find good quality options in many gardening stores!

  1. Food & Nutrients

This is the part where those added extras come in! We have seen plenty of people brew compost tea using nothing but natural, healthy compost and a bucket of water! Although it is true you can get finer end-results when incorporating additional food and nutrients, it is possible to keep things simple if your compost is good enough.

Assuming you do want to add in some additional extras, here are some of the most common and popular choices:

  • Molasses
  • Liquid seaweed
  • Liquid Kelp
  • Work castings
  • Fish hydrolysate

Each of the above, along with a range of other ingredients that can be added, offer food and additional nutrients for your compost tea that can provide additional benefit to your cannabis plant.

Ingredients such as molasses feed the microorganisms in the compost, helping them to multiply dramatically, while liquid kelp can help to improve the overall health of the soil as well as providing a good source of food for the organisms that cycle nutrients and feed plants.

Many organic food sources can be added as food for the organisms in cannabis plants, and these can go a long way in the successful cultivation of your favorite bud .

The final core ingredient to compost tea is oxygen, which is vital to aerate the compost tea and allow microorganisms to thrive. This can be tricky to get right as fast-growing microorganisms can require more oxygen than is available, leading to potentially toxic materials. A good air pump that is large enough to provide a 6 ppm threshold will usually be adequate for most brewing jobs.

We could talk all day about the various ingredients needed for compost tea, but the bare bones are a healthy compost, good oxygen system, and additional nutrients – you shouldn’t go too far wrong with these!

In terms of equipment, a large bucket, a decent air pump, an aerator and a good pair of panty hose or a mesh bag will be your most vital items, and anything else you wish to use can be an afterthought – if you have these items, you have all you will need.

How to Make Compost Tea

Okay, so you have your compost, you’ve got your nutritional additions , and you have your equipment. Now what? Below is our simple step-by-step method for making a good quality compost tea, remember that there are of course more complex ways you can do this, but we want to keep things simple!

  1. The first thing you want to do is to fill your bucket with water. If you have used water that contains chlorine, you will need an aerator to remove it. If you have used fresh water with no chlorine, then it is possible to make compost tea without using an aerator.
  2. With your water in the bucket, you need to attach your air pump to the outside of the bucket and (if necessary) your aerator device also requires connecting at this stage.
  3. Using a clean pair of pantyhose or a mesh bag, place your compost inside with any other ingredients you want to use. You can also buy pre-built compost mixtures if you aren’t ready to go it alone yet!
  4. Tea brewing is pretty simple. Once you have your set up going, the only thing you need is patience! Usually, compost tea will take somewhere between 24 and 36 hours to brew, and during this time it is important to monitor temperature.
  5. The optimum temperature for healthy compost tea is between 65-85 degree Fahrenheit. A temperature too warm and you run the risk of the tea brewing too fast, which can make it too anaerobic and allow for pathogens to grow. If the brew is too cold, then it can slow down the process and prevent microorganisms from populating full stop. Keep your brew out of direct sunlight.
  6. If you are opting to add additional ingredients, then you can do this during the brewing process. You can find tonnes of compost tea recipes online, which will tailor to specific needs, so check out what you are looking for to find exact quantities. As a general rule of thumb, most foods and nutrients are either added right at the beginning of the brewing process, or towards the end. However, this does depend on the product you are adding, for example, Sea Green is added just before you apply the tea to your plants, whereas food designed for bacteria should be added halfway through, so always check first!
  7. That’s it! You can apply your tea either to the roots, or the leaves, or even both anytime within 26 hours of brewing. We advise against using the batch anytime after this.

Round-Up: Should You Be Adding Compost Tea to Your Cannabis Garden?

There is no denying that compost tea has taken the cannabis market by storm in recent years. You can now look anywhere online and find a raft of information, techniques, and all-singing, all-dancing products!

Yes, compost tea is beneficial – but it doesn’t have to be hard work! We hope by following our simple guide, you are feeling more confident about knocking up your own batch of compost tea, but first let us know your thoughts in the comments below!

Our complete guide to making compost tea, the organic way to boost the health of your cannabis garden.

The best compost tea recipe

Copy article link to clipboard.

Link copied to clipboard.


  1. Benefits of compost tea
  2. How long does it take to make compost tea?
  3. What is the best compost tea recipe?
  4. What you need to make compost tea
  5. Steps to making compost tea
  6. Can you burn your plants with compost tea?
  7. Bottom line on compost tea

If you’re a cannabis grower interested in the zero-waste movement , compost tea could be a good place to start. This is not the kind of tea that you pour into a mug and sip. Compost tea is an organic mix of active nutrients and microorganisms steeped in aerated water. The brew packs a nutritional powerhouse for soil, roots, and leaves, introducing healthy fungal colonies (think of how probiotics benefit the digestive system) and beneficial bacteria to cannabis plants. The results are a boost in plant growth and protection from disease.

Benefits of compost tea

Though not all growers agree on whether compost tea is any more effective than ordinary compost, some cultivators have pinpointed these potential benefits:

  • Reducing the presence of weeds and pests, which consequently helps cannabis plants fend off diseases such as blight. Compost tea may shield marijuana from pathogens that could harm or even kill the plant.
  • Infusing the cannabis plant with a strong dose of nutrients, which can potentially increase plant size due to a strengthened immune system from a diversity of trace minerals.
  • Eliminating the need for chemical fertilizers that ultimately harm the soil and the environment when contaminated water leads to runoff and seeps into public water supplies. With compost tea, you are creating something 100% organic, which facilitates a thriving and self-sustaining ecosystem.
  • Maximizing water retention in the soil, meaning less wasted water.
  • Improving the overall health of the plant with a beneficial cocktail of fungi, bacteria, protozoa, and nematodes of multiple species.

Some cultivators have pinpointed potential benefits of compost tea. Photo by: Gina Coleman/Weedmaps

Image lightbox

How long does it take to make compost tea?

Making compost tea is a fast process that lasts between 24 and 36 hours. A slightly longer brew will increase the amount of beneficial microbes, but you should not brew the tea for longer than three days. Doing so will cause the microbes to die out for lack of food supply. One benchmark to know if the brew is fresh and effective is that it will emit an earthy fragrance. Some gardeners claim that compost tea will stay fresh in the refrigerator for up to 30 days, but there is no reason to keep it on hand this long if you’re ready to apply the treatment.

Apply compost tea on sunny mornings when the plant stoma are most open to receiving and absorbing the mixture. A rule of thumb is to do it when dew conditions are favorable, so if you don’t have time to apply the tea early in the morning, do it at dusk.

How do you make compost tea to enhance your cannabis harvest? Here is an easy compost tea recipe, complete with all the necessary steps and ingredients.

What is the best compost tea recipe?

To whip up the best compost tea to strengthen your cannabis plants and make them more resilient, you’ll need five main ingredients:

  • Compost: The first and most important ingredient is compost with a rich biome of nutrients and microorganisms. The more developed the compost’s fungal colonies, the stronger the compost tea will be. Organic compost from local sources provides the best foundation for this recipe.
  • Kelp: This sea ingredient feeds the fungal colonies and aids in development, ultimately activating the potency of compost tea.
  • Molasses: More commonly used as an ingredient in baking, molasses feeds the helpful bacteria, encouraging them to proliferate and maximize the benefits of compost tea. For an extra infusion of potency, try blackstrap molasses, which is saltier and more bitter than the ordinary kind, making it better for brewing compost.
  • Worm Castings: Though not the most appetizing ingredient, worm castings are dense in easily absorbed nutrients and introduce a host of microorganisms to the tea.
  • Fish Hydrolysate: Like kelp, fish hydrolysate feeds fungi, but it also contains nitrogen and chitin, the latter of which serves as an immune booster to marijuana plants.

Once you’ve gathered these ingredients, you’ll need a few supplies before the tea brewing begins.

What you need to make compost tea

This simple compost tea recipe doesn’t require many supplies in addition to the main ingredients. You’ll just need:

  • Non-chlorinated water. It can be tap water that sits for 24 hours or, for a really organic experience, rainwater.
  • 5-gallon bucket, though larger gardens may need a larger size.
  • Watering can or spritzer.

In addition, if you would like to aerate the compost, which is recommended, you will need:

  • Air pump.
  • Aquarium bubbler.
  • 400-micron mesh bag or breathable fabric, such as pantyhose or any porous cloth.

The aquarium bubbler, kelp, and fish hydrolysate can all be purchased at a fish or aquarium supply store.

Steps to making compost tea

The three steps to making compost tea are straightforward:

  • Build the brewer: Place the aquarium bubbler in the bottom of the bucket and use plastic tubing to attach it to the air pump outside the bucket. Fill the bucket with non-chlorinated water.
  • Fill the teabag (aka the mesh bag): Remove any worms from the compost before you proceed with this step. Then, pour the tea ingredients into the mesh bag.
  • Brew the tea: Carve out at least a 24-hour period to let the pump run continuously and brew the tea. Be prepared to apply the compost tea to the soil as soon as possible, preferably within 36 hours of adding the bag to the brewer.

There is an optional fourth step. You can supplement the compost tea with items in addition to the kelp, molasses, and castings. Try a biologically active product such as Actinovate along with supplemental food for fungi and bacteria, if desired.

Once the compost tea has brewed, apply it to the soil. You can also spray some of the mixture onto the leaves for a more thorough treatment. This usage varies from plain compost, which is applied only to the soil and doesn’t directly reach every part of the plant . Foliar spraying is one benefit of compost tea, offering a more well-rounded treatment than might otherwise be possible.

Can you burn your plants with compost tea?

It is possible to burn plants with compost tea, especially if you are using a compost high in nitrogen. Manure-based composts tend to contain higher levels of nitrogen, so be sparing as you treat the soil if you are using this type and don’t spray it on the leaves. Otherwise, you can be more liberal in your treatment of the soil, especially since compost tea loses much of its potency within a few hours of brewing and long-term storage is not feasible.

Bottom line on compost tea

Compost tea is relatively easy and inexpensive to make. But it has a very short shelf-life and needs to be applied to the soil immediately to enrich the health of cannabis plants.

The best compost tea recipe Copy article link to clipboard. Link copied to clipboard. Contents Benefits of compost tea How long does it take to make compost tea? What is