Water plants with coffee

Diluted Coffee For Plants: Can You Water Plants With Coffee

Many of us start the day with some sort of coffee pick me up, whether it’s a plain cup of drip or a double macchiato. The question is, will watering plants with coffee give them that same “perk”?

Can You Water Plants with Coffee?

Coffee used as a fertilizer is not exactly a new idea. Many gardeners add coffee grounds to compost piles where it decomposes and mixes with other organic matter to create some fantastic nourishing soil. Of course, this is done with grounds, not the actual cold cup of coffee sitting here at my desk. So, can you water your plants with coffee proper?

Coffee grounds are about 2 percent nitrogen by volume, nitrogen being an important component for growing plants. Composting grounds introduces microorganisms that break down and release the nitrogen as it raises the temperature of the pile and aids in killing weed seeds and pathogens. Very useful stuff!

Brewed coffee also contains measurable amounts of magnesium and potassium, which are building blocks for plant growth as well. Therefore, it seems a logical conclusion that watering plants with coffee might indeed be very beneficial.

Of course, you wouldn’t want to use the cup sitting in front of you. Most of us add a little cream, flavoring, and sugar (or sugar substitute) to our Joe. While real sugar would not pose a problem to the plants, milk or artificial creamer won’t do your plants any good. Who knows what effect any of the many artificial sweeteners on the market would have on plants? I’m thinking, not good. Be sure to dilute before watering plants with coffee and don’t add anything else to it.

How to Water Plants with Coffee

Now that we have ascertained that we should use diluted coffee for plants fertilizer, how do we do it?

Coffee has a pH of from 5.2 to 6.9 depending on the variety and preparation. The lower the pH, the more acid; in other words, coffee is pretty acidic. Most plants grow best in slightly acid to neutral pH (5.8 to 7). Tap water is slightly alkaline with a pH greater than 7. Therefore, using diluted coffee for plants can increase the acidity of the soil. Traditional chemical fertilizers, the addition of sulfur or allowing leaves to decompose on soil surfaces are methods to decrease soil pH levels. Now you have another option.

Allow your plain brewed coffee to cool and then dilute it with the same amount of cool water as coffee. Then simply water acid-loving plants such as:

  • African violets
  • Azaleas
  • Amaryllis
  • Cyclamen
  • Hydrangea
  • Bromeliad
  • Gardenia
  • Hyacinth
  • Impatiens
  • Aloe
  • Gladiolus
  • Phalaenopsis orchid
  • Roses
  • Begonias
  • Ferns

Water with the diluted coffee just as you would with plain tap water. Don’t water plants that do not like acidic soil.

Don’t water every time with the diluted coffee fertilizer. Plants will sicken or die if the soil becomes too acidic. Yellowing leaves may be a sign of too much acid in the soil, in which case, abandon the coffee irrigation and repot plants in containers.

Coffee works great on many types of flowering indoor plants but can be used outside as well. Diluted coffee adds just enough organic fertilizer to encourage bushier, healthier plants.

The Effect of Caffeine on Plant Growth


Life Science, Plant Biology


Middle School, Seventh Grade

Difficulty of the Project




Safety Issues

No known safety issues.

Time Taken to Complete the Project

About three weeks.


The goal of this middle school science fair project is to examine the effect of caffeine on plant growth.

  • 1 packet of mung beans
  • 3 gardening pots
  • Enough soil to fill the 3 pots
  • Gardening utensils
  • Tap water
  • Caffeine tablets
  • Coffee powder
  • 2 beakers
  • 1 measuring cylinder
  • 1 digital weighing scale
  • 1 black marker


Some plants seem to benefit and grow faster when caffeine is added to the soil, while others seem to become stunted or grow slower. There are also some plants that are not affected by the presence of caffeine in the soil. Caffeine can be introduced to the soil by sprinkling grounded coffee over the soil, adding leftover coffee to the pot or watering with a caffeine solution made by dissolving a caffeine tablet in water. The grounded coffee is actually organic matter and will help in adding nutrients to the soil. It will also attract worms that feed on the grounded coffee and at the same time help to aerate the soil.

The mung beans watered using the coffee mixture will grow the fastest.

  1. The independent variable is the solution used to water the plants – water, caffeine solution and a coffee mixture. The dependent variable is the growth of the mug bean plants. This is determined by measuring the height of the plants every day using a ruler. The constants (control variables) are the size of the pot, the concentration of caffeine and coffee, the amount of sunlight, the temperature of the environment (which will remain at room temperature) and the amount of water added daily.
  2. Fill the 3 pots with equal amounts of soil. Plant ten mug beans in each pot and allow them to germinate. Additional seeds can be placed in the pots in case some of the seeds do not germinate; the additional plants can be removed later.
  3. For the first 5 days, water the 3 pots with tap water only. Allow the seeds to germinate for the first 5 days.
  4. After 5 days, measure the height of the 10 plants in each pot. Add up the individual heights and divide by 10 to obtain the average height. Record the average heights in a table, as shown below.
  5. Prepare the caffeine solution by dissolving 10g of caffeine tablets in 100ml of water in a beaker. Label the beaker ‘caffeine’. Similarly, add 10g of coffee to 100ml of water in another beaker and label it ‘coffee’.
  6. Label the 3 pots ‘water’, ‘caffeine’ or ‘coffee’. Over the next 10 days, water the pots once a day with 100ml water, caffeine solution or coffee mixture, according to the labels on the pots.
  7. Measure and calculate the average height of the mung bean plants every day for the next 10 days. Record all calculations in a table.


The results of the experiment were, mung beans grew faster in soil with caffeine.

The hypothesis that mung beans watered using a coffee mixture will grow the fastest has been proven to be true. The effect of caffeine on plant growth is still a subject under study. Using grounded coffee in garden lawns is a common practice to make plants grow faster. However, coffee also contains other ingredients like potassium and phosphorous, which are known to enhance plant growth. Experiments on plant growth using only caffeine have resulted in the plant leaves becoming wrinkled, turning brownish and exhibiting retarded growth.

Once a week we will be featuring a fun and/or educational activity you can try at home or in the classroom. This week the writers on the Heifer Blog have been taking a look at coffee-growing communities all over the world, where hunger and poverty is a common problem. Heifer is helping these farmers by diversifying their income and teaching them about our model for sustainable community development.

You can improve your own sustainability and lessen the negative impact of throwing away garbage that can be recycled. Try this experiment to see the benefits for yourself, with coffee grounds and growing plants.

Do you (or anyone in your house) drink coffee? Many people who do, throw the coffee grounds in the trash when they are done. However, there are many ways you can recycle the grounds, like as fertilizer to help your plants grow healthier and faster. Besides the obvious benefits of recycling instead of throwing away, you can use the natural fertilizer and cut down on the costs of buying fertilizer from the store and/or using chemical fertilizers.

Coffee grounds make a great natural fertilizer

What you need:

  • Two pots (the smaller the better)
  • Potting soil
  • Small stones
  • Seeds
  • Measuring tape
  • Coffee grounds

Coffee grounds make a great natural fertilizer because they are rich in nitrogen, which provides energy to help the bacteria turn organic matter into compost. For the best results, mix the coffee grounds into the soil and sprinkle some around the plants, before you water them.

Put the pebbles at the bottom of both pots. Fill one of the pots with a soil/coffee ground mixture. Fill the other with just soil. Make a trench with your finger in the soil of both pots, and sprinkle seeds in the trench. Cover the seeds with soil, and fully soak the soil with water. Label each pot so you can keep track of your results. The pots should be placed in a well-lit area, and watered every day. Before watering the pot with the coffee ground/soil misture, sprinkle coffee grounds on top of the soil.

Measure the size of the plant with the measuring tape daily, and write the measurements down on a chart with three columns. Column 1 for the date, Column 2 for Pot #1, and Column 3 for Pot #2.

You can also check out Heifer’s lesson plans and classroom activities related to sustainability, recycling, etc., in the Classroom Resources section of our website.

Use Diluted Coffee to Fertilize Plants

You know that last bit of coffee that always seems to be left in the carafe? Don’t just pour it down the drain — you can use it to fertilize your container-grown plants. Coffee grounds (and brewed coffee) are a source of nitrogen for plants, which is the nutrient that produces healthy green growth and strong stems. Coffee also contains calcium and magnesium — both of which are beneficial to plant health.

To use coffee as a plant fertilizer, you’ll need to dilute it. It should look like weak tea — see the photo for an example. If you aim for about 1/4 coffee and 3/4 water in your mixture (depending on how strongly you brew your coffee), that’s about right, but you don’t have to be fussy about it. You can use coffee fertilizer on your potted plants, houseplants, or in your vegetable garden. Coffee and coffee grounds can be acidic, but since we’re diluting it so much, that’s not really a problem unless you’re watering the same plant with it every day.


A good rule of thumb is to feed and water your plants once a week with a weak coffee solution. They’ll appreciate the additional nutrients, as well as the water.

Bob Morris Coffee grounds add some, but not all, nutrients needed by plants.Bob Morris So-called “giant” fig trees may produce larger fruit, but smaller fruit gnerally has more flavor.

Q: Is it a good idea to work coffee grounds into the soil in flower beds? Does it help?

A: Yes, coffee grounds are good. They add some, but not all, nutrients needed by plants and improve soil structure for better water drainage and air movement to the roots. This, in turn, improves plant growth. Add it to the soil just before planting.

Coffee grounds are better if composted first, but adding them raw is one step in helping improve the soil.

Don’t rely on coffee grounds alone. For instance, don’t go to your local Starbucks and add 100 pounds of coffee grounds to a 4-by-8 planter or raised bed and call soil preparation done.

Adding only coffee grounds is like eating only corn and expecting to maintain a healthy diet. You need a variety of different foods to remain healthy. Your garden also needs a variety of healthy ingredients from different amendments for plants to remain healthy.

A variety of minerals are needed by plants. Provide this by decomposing a wide variety of things in your garden soil in addition to coffee grounds.

There is plenty of nitrogen in raw coffee grounds, but this nitrogen isn’t yet released or available for plants. Releasing this nitrogen to plants is done through composting or letting it sit in the soil and decompose. That’s what composting is: It’s controlled decomposition.

Other things to add in small quantities to garden soil include wood ashes (no ash from coal or petroleum sources), finely ground kitchen scraps (use a blender with a little bit of water to grind up scraps to a small size), shredded paper with black ink, shredded cardboard, sawdust from wood (not particle board), leaves and grass clippings.

When added to garden soil, these ingredients rot over time and release minerals and nutrients. Make sure they are pulverized. The smaller the pieces, the faster they rot.

Stop and think about it. Compost piles mix a wide variety of things but lumped together and managed so they rot faster together. Finished compost makes a better soil amendment with a wide variety of plant nutrients.

Q: I have a Patrick giant fig tree. Is it the same as a Texas giant? If they are different, which one produces bigger fruits under the same conditions?

A: I have never grown any of the so-called “giant” fig trees, because they never interested me much. I focus more on the taste of the fruit, rather than its size. I have grown about 15 to 20 different varieties in the Mojave Desert climate, but none of them are marketed as “giant.”

I have produced figs from fig trees that were quite large. I am quite certain this was the breba, or first crop, not the main crop.

I believe the reason is that there was less fruit on the tree because of winter pruning, so the ones remaining got quite large. The less fruit on a tree, the larger the fruit will become. The amount of fruit produced by a tree has more to do with the number of leaves, their size and the percentage of leaves in full sunlight.

My experience is that smaller fruit has more flavor than large fruit. And smaller fruit is usually more nutritious. This is because the minerals and nutrients in the fruit are more concentrated.

So large-sized fruit has never been particularly attractive to me. To me, large-sized fruit is more about “bragging rights” than flavor.

Q: What is the best way to remove scale and aphids on bay laurel?

A: Scale is insects that have soft bodies and can crawl around from place to place when they are young. Once they have found a place to live, they build a house around it called a scale. Underneath that scale is a soft-bodied insect that is sucking plant juices.

The scale on the outside protects it from contact insecticides. Ants will move their young around just like they will aphids. The trick is to catch scale insects in their crawler stage, when they are very susceptible to just about anything, including soap sprays.

The most effective sprays are spray oils: horticultural oils, supreme oil, dormant oil, a bunch of different names. Many of them are petroleum oils derived from paraffin or mineral oil.

It’s a good idea to apply these oils twice during the winter and again in the spring after the plant has flowered. There are traps available to know when to spray, but you have to know which scale insect you are dealing with. So repeat applications of spray oils during the growing season is usually recommended and very effective.

Bob Morris is a horticulture expert and professor emeritus of the University of Nevada, Las Vegas. Visit his blog at xtremehorticulture.blogspot.com. Send questions to [email protected]

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While we humans might rely on coffee to wake us up each and every day—not everyone is a morning person, okay?—we don’t realize that the plants around us could actually use a little caffeine pick-me-up themselves.

Apparently, coffee is a great source of nitrogen, and plants that enjoy more acidic soil can benefit from certain levels of nitrogen, like blueberries, azaleas, and rhododendrons. According to The Spruce, if you plan on doing this, you’ll need to keep a close eye on your plant. If you’re “watering” it with coffee and the leaves of the plant start yellowing at the edges or turning brown, it may mean that the liquid coffee is adding too much acid to the soil. A solution to this could be watering down your coffee before you pour it onto your plant.

Another reminder: The coffee you water your plant with needs to be black. That may seem obvious, but pouring out your leftover brew that contains sweeteners or dairy could attract pests, like gnats. Even if you’re just using black coffee, you should stick to doing this only once a week.

What’s left over in your coffee pot isn’t the only beneficial part of coffee for your plants—the leftover grounds can also benefit your growing green friends as compost or fertilizer.

Sprinkling grounds into your plant’s soil not only serves as a mild acid fertilizer, but it can prevent slugs from appearing and also keep pesky animals out, like cats or rabbits.

For those of you who enjoy a cup or two (or three or four) a day, this little hack could definitely help cut back your coffee waste.

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Caffeine and plant growth
The effect of adding caffeine to the soil and its effect on plant growth is a subject that has been studied for quite some time. Some plants seem to benefit and grow faster when caffeine is added to the soil, while others seem to become stunted or grow slower. There are also some plants that are not affected by the presence of caffeine in the soil.
Caffeine can be introduced to the soil by sprinkling grounded coffee over the soil, adding leftover coffee to the pot or watering with a caffeine solution made by dissolving a caffeine tablet in water. The grounded coffee is actually organic matter and will help in adding nutrients to the soil. It will also attract worms that feed on the grounded coffee and at the same time help to aerate the soil.
Many gardens are known to add grounded coffee to the soil in order to accelerate plant growth. However, it is not clear whether the improved growth is due to the caffeine or the presence of potassium and phosphorous in coffee. It is also possible that caffeine retards plant growth but the presence of potassium and phosphorous in coffee reverses this effect.

Can You Water Plants With Coffee? The Drink Has Some Hidden Horticultural Benefits

Your morning cup of Joe. That caffeine injection. The old “oh sure I’ll make a big pot, I’ll get through it” attitude. Next minute, you find yourself with tummy ache, palpitations, and a lot of left over coffee. So what’s a person to do? Knock it back and hope for the best? Y’all, no. Think of your nerves. OK, but coffee is expensive. You don’t want to waste the bloomin’ stuff do you? Talking of bloomin’ maybe you could about give it back to mother earth? Can you water your plants with coffee? Because I’d love to treat my foliage to the finer things in life.

Well, guys, it seems that, according to gardeningknowhow.com, your cold cup of coffee might actually be just the ticket. Owing to it having nitrogen, which is good for killing weeds, and magnesium and potassium, which are both also excellent for helping promote very happy and healthy plant growth. Hell yes to that, am I right?

However, there are some warnings alongside using coffee to water your plants. First of all, guys, when it comes to watering plants with coffee, we’re talking black coffee. Don’t pour your double mocha frappucino with extra syrup on your plant, whatever you do.

It’s best to dilute it as it may be too acidic on its own. As home decor site The Spruce states:

“If you decide to try watering houseplants with coffee, keep a close eye on your plant. If the foliage starts yellowing or the tips of the leaves start turning brown, it’s a sign that the coffee is adding too much acidity to the soil. It’s not a bad idea to dilute your coffee with water, especially if you prefer your daily cup of java on the strong side.” Coffee ground, Coffee residue is applied to the tree and is a natural fertilizer, Gardening hobby

And everyone, the good news doesn’t stop here. Oh hell no. Coffee grounds also make for great composting material. So, if you make sure you keep those handy little caffeinated nuggets for the compost heap, you will build up quite the healthy soil. According to the Royal Horticultural Society (RHS), coffee grounds are great for a healthy garden. “Coffee grounds: provides low levels of nutrients and can either be used in small quantities around plants or composted before adding to the garden,” the RHS writes.

Not only does it make for great compost but it also makes for a great accompaniment to compost’s best friend: earthworms. Yes, love them or hate them, they are flipping great for your garden. And it seems that, according to a study from Extension Urban Horticulturist and Associate Professor at Washington State University Dr. Linda Chalker-Scott, they are just as crazy for coffee as you are:

“Some larger bioconsumers, including earthworms use coffee grounds as a food source. The fact that earthworms pull coffee grounds deeper into the soil may account for noted improvements in soil structure such as increased aggregation following the application of coffee grounds.” Macro shot of red worms Dendrobena in manure, earthworm live bait for fishing

Yikes. So not only is this a good way to recycle, but it is providing some serious chow for those little slimy garden pals.

I guess you might be reading this as a non coffee drinker, and actually despairing right now. Well firstly, wow how do you get up in the morning? Secondly, worry thee not. Because, if you pop down to your local cafe, I am sure they will be more than happy for you to take their old used up coffee grounds to make your garden as happy and healthy as it deserves to be.

Use Coffee Grounds As An All-Natural Cannabis Fertiliser

It may come as a surprise to many, but every time you empty your coffee grounds into the bin, you are effectively throwing away a very cheap, effective, and natural fertiliser that could be used to nourish your cannabis garden or indoor growing operation. Not only that, but coffee grounds can also help to cover up obvious smells and defend your crop against parasites and several other pests.

Coffee grounds are easily accessible and may appeal to a wide variety of growers, especially those who are environmentally minded. Coffee grounds are entirely vegan, and using your own grounds or those sourced from the local economy means minimising the transportation involved. Organic coffee grounds can also be used for those who are especially concerned about pesticide use and aim to keep their garden completely organic.

Here are some of the main reasons why using coffee grounds in your cannabis grow is a fantastic idea.


Adding coffee grounds to your soil and compost mixes will add to the acidity of the soil. Cannabis plants thrive in an environment that is slightly towards the acidic side of the pH scale, preferring levels of around 6.0–6.5. Soil pH that is either too high or too low will impede the growth of your plants, so it is important to monitor these levels closely. Coffee grounds can be used as a “pH down” product, acting to reduce the pH of your soil if it is too alkaline. Additionally, it’s entirely natural and won’t harm the environment when disposed of later down the line.


Every time you remove the grounds from your coffee machine, they can be added directly to your compost bin. This waste material contains nutrients that will keep your cannabis plants healthy and vibrant. When added to a compost bin, as opposed to being dropped directly into the soil, coffee grounds serve as a green waste, which can then be mixed with carbon-rich brown waste such as straw and wood ashes. Such a mix is excellent to generate the heat needed to break down the materials into a good-quality compost.

Coffee grounds provide noticeable levels of nitrogen into the compost mix. This key mineral is vital to plants as it is a major component of chlorophyll, the green pigment that plants utilise in order to conduct photosynthesis. Using coffee grounds will offer your plants a good supply of this mineral and will help to avoid any potentially damaging deficiencies during the grow cycle.


Perhaps one of the most challenging elements of growing cannabis is pest control and management. Many small creatures have an appetite for the nutrients within the cannabis plant and can do a great deal of damage to a crop when attacking in numbers. If spotted early, many invasions can be dealt with, although preventative measures are much more effective than curative ones. Coffee grounds offer multiple benefits when it comes to preventing pests from obtaining a foothold.

Firstly, the acidity of the material is reported to help stave off parasite infestations. Secondly, the small and sharp grounds have a micro-abrasive property. This means that insects making their way towards your plants via the soil may be put off due to the sharp minefield of coffee grounds that obstruct their path.

As well has offering defence against critters, coffee grounds are also said to assist against fungal invaders too, such as Fusarium, Pythium, and Sclerotinia.


Worms are an important asset in many cannabis gardens, and act as little compost producing machines. Keeping worms for this reason is known as vermiculture. The worms add the organic materials they are given and their poop, or castings, are used as compost within the garden. Coffee grounds can be fed to worms, as long as they are given other organic materials to form a balanced food intake that isn’t too acidic.

This post is focused on coffee grounds for your marijuana grows (and its pros).

Coffee ground’s an abundant organic-material source, ideal for adequate vegetative behavior of marijuana plants; coffee contains many of the minerals required by crops, and high acidity – very useful when growing in alkaline soil/substrate.

This way, many growers use coffee grounds to improve their crop yields; let’s focus on coffee properties – ideal partner for cannabis.


Its nutritional content would be enhanced and supplemented; coffee could be added to ecological and chemical compost – cheap, simple, fast way to improve your crop compost.


Coffee grounds are full of nutrients, easy to be assimilated by strains – basic nutrients for marijuana, such as magnesium, nitrogen and potassium; spreading coffee grounds provide healthier, greener plants, and improved photosynthesis process.

Acidity balance

As previously mentioned, coffee increases substrate acidity – if soil acidity’s excessive, an alkaline substance’s added (powdered lime): soil acidity would be stabilized, and the strains would take advantage from coffee benefits without the negative effects of acidity.

Insect repellent

Coffee grounds can also be used as organic natural insecticide, improving plant resistance against insects, fungi (Fusarium, Pythium and Sclerotinia) and plagues – red spider, slug, caterpillar, snail; very good ecological anti-plague option – unbeatable price.

Worm food

Coffee grounds could be poured onto garden compost bin to produce quality compost thru organic waste; very useful for vermiculture – compost production thru earthworm excrements: this process provides earthworm humus – concentrated earthworm excrement (after organic feeding); this humus contains ideal nutrient levels for optimum plant development, and microbes which decompose the soil in more beneficial ways for crop feeding.

As previously mentioned, coffee grounds are multifunctional substances for cannabis crops – just enjoy coffee-ground benefits.

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Natural home-made fertilizers

Cannabis, like any other plant, may also need extra help for better growth.

There are natural fertilizers that you can make yourself in a simple way.

Most plants can use a fertilizer or organic substrates to help them grow healthy, vigorous and full of vitality. Natural fertilizers have been used for centuries and have served to obtain abundant, disease-free crops with spectacular growth as they provide the plant with all the minerals and organic compounds it needs to grow healthy and strong.

Here we show you some of the best known and best results give for the crop of our beloved plant. 😉

However, if you prefer to use fertilizers available on the market, remember that in our “Fertilizers and Stimulants” section you can find them at the best price.

You may also be interested in:

– Irrigation water as a key factor in indoor cultivation

– How to use the potassium soap correctly

– 10 tips for autoflowering cultivation

Coffee grounds

Coffee grounds, excellent fertilizer for the growth phase.

A fertilizer for the growth phase

The use of coffee grounds as a natural fertilizer has long been well known, and it is also one of the most commonly used homemade marijuana fertilizers.

Coffee grounds are acidic and favour the development of acetic bacteria in the substrate, containing about 2% nitrogen and other organic nutrients.

A good way to prepare a good fertilizer for marijuana is to add the coffee grounds to your compost or composting tank, or spread them and mix them with the substrate that will be in contact with the roots of your plant, but you should control well the pH because they can leave the substrate too acidic.

Another way to use coffee is to dilute the coffee ground from the coffee machine in one liter of water, and let the mixture stand for 24 hours. After this time we already have a good dose of fertilizer for our plants. In this case, we do not use the sediment directly as fertilizer, but the mother water (water in contact with the unsoluble coffe ground) derived from the digestion of the sediment (sedimented coffee).

Personally, I prefer to use the sediment and mix it with the substrate, it is an excellent fertilizer for the growth phase.

Wood ashes

Wood ash, very effective in preventing pests.

Fertilizer for the final flowering phase

Always using wood from broadleaves trees; it’s another good natural fertilizer for marijuana. We can get the wood ashes from a barbecue made with logs or from a chimney in which we use only wood. The result of the wood combustion is a substance rich in potassium and phosphorus (10% in the form of potassium oxide), so we have a mineral fertilizer suitable for the final flowering phase, used individually or combined with some resin enhancer.

One way to prepare the ashes for fertilization is to collect it soon after the wood has burned and store it in a dry place. It’s best to apply mixed with other organic substrates as it is almost exclusively a mineral residue. Ashes are also very effective in preventing pests.

Another way to use wood ashes is as a fertilizer solution, which, as with the coffee grounds, is prepared by diluting the ashes in a little water, and let them rest for a few hours (making a breeding ground).

And now you may irrigate your cannabis plants in flowering phase with the nutrient solution. Another of the most useful homemade fertilizers for your collection.

Banana Tea

Banana tea provides amino acids assimilated by the plant

Full cycle flowering fertilizer

This fruit is known for being one of the most potassium-rich natural products. Potassium is a key element, which is used in all stages of cannabis plant development, and is also one of the three main macronutrients component of NPK (you can see it on the label), which we can all see in regular commercial fertilizers.

Potassium helps the plant assimilate sugars, starches and carbohydrates in general, which is why it is so essential for the plant’s flowering, as it helps to increase energy reserves and the construction of complex carbohydrates that give structure to leaves, stems and buds.

Potassium is also essential because it is associated with the biosynthesis of proteins related to terpenes, the absorption of water by the roots and the regulation of the stomata cell guards for its opening and closing.

In addition to this essential element, banana tea also provides amino acids assimilated by the plant so that we can say that it is an organic-mineral fertilizer.

A good way to prepare this potassium-rich fertilizer tea is to boil 3 banana peels in a liter of water, adding a little sugar. Once the mixture is cold, remove the banana peels and use the resulting liquid to irrigate our marijuana plants.

This tea is applied during the last six weeks of flowering. With this you will get up to 20% more fattening in your buds. You can also do it using honey, or molasses from sugar cane instead of pure white sugar.

A good fertilizer for marijuana, without a doubt, one of the best.

Nettle Tea

Nettle tea is a product that provides insect repellent plant active ingredients.

Fertilizer of foliar application and preventive insecticide

Nettle tea (urtica urens) rather than a fertilizer is a product that provides active plant principles of repellent activity on insects such as aphids, whiteflies and mites, but can also be considered fertilizer because of its high content in organic nitrogen and mineral components.

Its application is foliar and it is very easy to prepare since we only have to follow the same steps as in the preparation of banana tea.

We may cook a good handful of nettles in a litre of water and the liquid obtained (already strained) is used to irrigate the plant.

You should be careful when collecting nettles, as they can produce skin irritation if you touch the plant directly whit no protective gloves to cut it for making an extraction or maceration.

It has a strong and characteristic smell, even there are brands of biocides/fertilizers that commercialize this type of preparations or fertilizers for cannabis as Agrobeta or General Hydroponics, even labelled as deficencies correctors . You can find it with the denomination of “Purín de ortigas” in Spain.

It’s a great product that enters us into organic agriculture as good natural fertilizers that they are.

Brewer’s yeast

Brewer’s yeast, rich in minerals, amino acids and proteins

Multipurpose fertilizer

Brewer’s yeast has normally been promoted as an excellent food for human use, but due to its wealth of minerals, amino acids and proteins it has been proposed as an excellent organic-mineral fertilizer, qualified also as a good natural fertilizer for plants.

And don’t confuse it with baker’s yeast. The yeast that we are going to use is nutritional, and corresponds with the residue that has left the yeast alive after fermenting with barley malt.

How to use it to make organic compost for marijuana plants?

Very simple!

The preparation we can make for fertilizing consists of a small spoonful of brewer’s yeast dissolved in a liter of water, we will get another good fertilizer, in this case for cannabis in flowering phase, because it is very rich in phosphorus and potassium. Due to its high content in other minerals and organic compounds we consider it as a multipurpose fertilizer… Just use it!

Egg shell

Egg shell, calcium deficiency correcting fertilizer

Calcium deficiency correcting fertilizer

An excellent calcium corrector that we can use in our preparations with marijuana fertilizers are also the homemade egg shell-based fertilizers.

This type of fertilizer is used to provide extra calcium to our marijuana plants. It is prepared by crushing in a mortar among six to eight eggshells, which are then put to digest using a litre and a half of water with a few drops of a diluted aqueous solution of hydrochloric acid (you may find as Salfumant name in Spain) for 24 hours. You must measure the pH of the resulting nutrition solution that should remain around 5.0.

After that time, the remaining shells are removed and the resulting liquid is filtered.

We already have our calcium-rich fertilizer for our marijuana. Calcium deficiency is not very common in marijuana, since it is a very common component in irrigation water that is not distilled or osmotized, but bear in mind that the marijuana plant requires almost as much calcium as nitrogen, and that is why many commercial brands of fertilizers for hydroponics incorporate it in their formulas.

Mix the resulting nutrient solution with some fertilizer rich in nitrogen for the growth phase, or phosphorus and potassium for the flowering phase, although you can use it as calcium corrector directly as long as you take into account the pH value.

Adjust the pH if you have too much acidic the liquid; remember that the appropriate pH values are 5.5 for the growth phase and 6.0-6.5 for flowering. The final root washing is best done at neutral pH 7.0.

Animal faeces

Animal faeces, one of the most universal fertilizers for marijuana

Full cycle fertilizer

Although it may not seem too pleasant, animal faeces are one of the most universal fertilizers for marijuana. It is a high-quality organic fertilizer. In order to use this type of homemade fertilizer for plants, it is necessary to collect the dried animal faeces from species such as sheep, goat, horse, rabbit, and cow, some bird species are also suitable, including the famous Guano, which is obtained from bats.

Before using this type of fertilizer, you must compost it for two months or more before adding it to the substrate of your garden, since the composting process may kill the seeds of bad weeds and transforms the nutrients into more profitable nutrient form by the plant. It is a fertilizer for marijuana quite complete in macronutrients and trace elements, one of the fertilizers for plants of general use for the entire cannabis vegetative cycle.

Lentils or bean tea

Lentils or bean tea, root stimulants rich in auxins

Root stimulants rich in auxins

Auxins represent a very important group of phytohormones that regulate plant growth and phototropism (movement of leaves and stems in search of light), causing the branches to grow vertically by elongation of plant cells.

Auxins have been traditionally used in gel form for root development in cuttings and seedlings, as is the case of Clonex, one of the best known marijuana products, and although it is true that the Auxins work very well in synthetic form, we can also find them in nutrient solutions formed by organic products such as seaweeds, and teas made of seeds rich in auxins, as happens with certain species of beans and other vegetables.

The teas made with these natural products are simple to prepare, as they are simply based on leaving the vegetables in water for a day, until they are completely hydrated. We can also heat this blend a little to help extract the nutritious compounds, then whisk it together and the resulting paste is strained. The final water or nutrient solution, contains the nutritious extract rich in auxins, and will be ready to use on roots and cuttings.

Another eco-friendly homemade cannabis fertilizer at your fingertips!!???

You may also be interested in:

– Homemade root stimulant for growth and flowering

– Growing marijuana with the SCROG method

– The apical pruning

Already elaborated fertilizers

And, if after reading all these ideas you don’t dare to make any of them, you will always have to go to your trustable grow shop and purchase a high quality manufactured fertilizer. In PEV Grow Shop we offer you fertilizers with specialization in hydroponic growing, showing a deep-rooted culture in nature and ecology.

One of the most complete fertilizer packs you can find at PEV Grow is the Canna Fertilizer Kit, with which you will have all the nutrients your plants need. This kit has 6 fertilizers that you can use depending on the phase of your plant is either growth or flowering.

Canna Fertilizer Kit

In any case, any brand that you choose, don’t forget to consult the fertilizer schedule charts that the manufacturer recommends, in order to optimize the results of your marijuana crop, either in yield, psychoactivity, aroma and flavor.

Canna Fertilizer Kit

With this Canna Fertilizer Kit you will have all the food your plants need to cover the full crop cycle, and of course at the best price on your Grow Shop trusted.


More infomation here
Canna Fertilizer Kit

We hope you liked this post.

Do not hesitate to share your experiences and concerns with us… and you know, if you have any technical questions do not wait any longer and call us…. we are here to serve you!??

See you at our next post! ?

Alan Martínez Benito CEO of Pev Grow, expert grower with more than 20 years of experience.
In constant struggle for the regulation of cannabis, mainly in the medicinal field.
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