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Using coffee grounds in indoor trees is becoming more and more popular. With an estimated 166 thousand bags of coffee consumed every year, many people use coffee grounds to help grow their Ficus. People then have a common question: Do Ficus trees like coffee grounds?
Ficus trees prefer neutral soil and are not particularly fond of coffee grounds which can acidify the soil. While coffee grounds can be used sparingly on Ficus, using coffee grounds too frequently can impact your Ficus’ ability to absorb nutrients from the earth.
So which Ficus species are more susceptible to using coffee grounds? And are there any alternatives to using coffee grounds in Ficus trees? Keep reading to find out more!
Just a quick heads up, over the past three years of running Plantpaladin, hundreds of people have asked for product recommendations. As such, You can find my favorite indoor bonsai tree here (link takes you to Bonsaiboy), my favorite outdoor bonsai tree (link takes you to Bonsaiboy), or have a look at all the products I recommend here.
Do Ficus trees like coffee grounds?
Ficus trees (also known as fig trees) of all varieties are becoming more and more popular.
People are looking for the best tips and tricks to help their trees bloom.
While all 850 species of Ficus thrive in indoor conditions, it is not uncommon for these trees to dry out if not cared for properly.
Ensuring that your Ficus has enough nutrients in its soil will be vital to the health of your trees.
While most people are using fertilizer for this, it’s becoming popular to use alternate methods of plant food such as coffee grounds.
Many people are now questioning if Ficus trees are like coffee grounds.
I wanted to get to the bottom of this, so I compared two of my own Ficus’, in which I used coffee grounds for one and fertilizer for the other.
I also visited my local botanical gardens and asked them their thoughts on Ficus trees like coffee grounds.
Finally, I asked 20 plant paladin readers who own Ficus trees ( both Ficus bonsai and general indoor Ficus trees) if their trees like coffee grounds.
Do Ficus trees like coffee grounds? – Quick facts
To summarize:
- Ficus owners should use coffee grounds sparingly on almost all of the 850 Fig tree species.
- Most Ficus trees prefer neutral soil – between 6.5 to 7.5 on the PH scale.
- Coffee grounds are a fantastic fertilizer for trees and shrubs that love acidic soil, such as blueberries; however, using this on trees like Ficus can reduce the soil’s PH level to 4.
- Increasing the acidity in a Ficus tree’s soil can impact the availability of essential nutrients, water absorption, and general plant growth.
- Increased acidity can, in turn, lead to dry, brittle branches, yellowing leaves, and in severe cases, the death of your tree.
- Using coffee grounds sparingly in your Ficus – about three times per year, in small doses, either mixed with compost or used via a liquid fertilizer will not impact your tree too much.
- Coffee grounds can also act as a promising pest repellent which is good if you keep your Ficus outdoors and ants attack it.
Do Ficus trees like coffee grounds – quick study
To test out if Ficus trees are like coffee grounds, I undertook a speedy (and unscientific) experiment on two of my own Ginseng Ficus trees.
For Ficus one, I used one cap full of regular liquid fertilizer (miracle grow 119649) with a balanced N-P-K ratio.
For Ficus two, I used 10 grams of used coffee grounds which I sprinkled and mixed with compost on the topsoil.
The experiment took place in April 2022, and I used one month’s worth of growth as the barometer of success.
With Ficus trees being relativity fast-growing, typically adding 1-3 inches of growth per month, if the tree with coffee grounds had grown the same amount as the tree with regular liquid fertilizer, I would call that a success.
The results
Plant one had grown by 3.5 inches at the end of the month in height
Plant two had grown 1.4 inches in size by the end of the month.
While these results both fall into the general height categories, Ficus grow per month; In my study, at least it was clear that using coffee grounds did impact the acidity levels of the potting soil, reducing its efficiency in growth.
Problem with the study
While this study was a quick, fun experiment for me to undertake, there are some significant problems.
First, the study was far from the laboratory conditions.
Ideally, both the Ficus trees would need to be kept in the same conditions.
My Ficus were kept slightly apart, which means that they can have slight changes in sunlight and temperature, which could have impacted the tree’s growth.
On top of this, the experiment concluded after one month.
A more definitive result would have meant using a more extended data period over a year.
The data showed that even the tiny period of one month shows at least some correlation between the speed at which a Ficus grows and the acidity in the soil caused by coffee grounds.
Why do people use coffee grounds in their Ficus?
The most common reason plant owners use coffee grounds in their Ficus trees is an alternative to using chemical fertilizers.
Coffee grounds are a natural substitute for fertilizer, which can burn Ficus trees if not calibrated correctly.
People also use coffee grounds on their Ficus as a form of pest control, specifically with ants.
Coffee grounds are also used in their Ficus trees to increase the acid of the potting soil of a Ficus tree.
For example, if you have used too much tap water on your Ficus and it has developed a lot of calcium, this will drastically increase the alkaline levels in your tree.
Using coffee grounds can be a good way of reducing the PH level down to a more natural level.
Finally, coffee grounds are also used in mulch to help keep Ficus trees moist when they dry out, such as in the middle of summer.
What are the best coffee grounds to use for Ficus?
The exact type and brand of coffee grounds used for your Ficus do not matter. Instead, it is essential that whatever coffee grounds you use are mixed in with compost or used in liquid fertilizer and not applied directly to your Ficus.
How to use coffee grounds in a Ficus tree?
So if you are interested in using coffee grounds in your Ficus tree as a fertilizer ( responsibly, of course), then there are three main ways tree owners should use this.
Coffee grounds used in Ficus trees should only be used when mixed with compost, mulch, or used as a liquid fertilizer. Avoid applying coffee grounds directly to the potting soil of a Ficus.
Let’s explore these options in more detail;
Using coffee grounds as compost for Ficus
So the option most of you will be thinking about is using coffee grounds as a part of the compost.
Using the coffee grounds this way will help reduce some of the acidity that the coffee grounds can cause.
Coffee grounds alone have a lot of nitrogen, an essential component of most fertilizers.
It doesn’t contain any phosphorous or potassium, both of which are essential to the health of your trees and make up the N-P-K ratio.
To get these elements, mix the potassium with other organic waste such as fruit, to increase these elements.
Aim for 15 to 20% of the compost to be made up of coffee grounds and have the reminder be organic material.
Apply this 2 to 3 times per year on the potting solid of your Ficus – [referbaly during the spring/summer.
Using coffee grounds as a mulch for Ficus
Much is fantastic at applying moisture back into your Ficus.
While Ficus are typically fantastic at being kept indoors, during the summer, when temperatures increase, you might be looking at ways to increase moisture during these warm periods.
Mulch then can be a great option to do this.
To add coffee grounds to mulch, use about 10 percent of coffee grounds mixed with organic material: straw, paper, hay, dead leaves, wood chips, and compost.
Adding mosses such as sphagnum moss can also prove beneficial.
Then gently spray with water, and your tree should remain moist throughout these dry periods.
Using coffee grounds as liquid fertilizer in Ficus
The majority of you reading this will already be fertilizing your tree.
Coffee grounds are used as a substitute for fertilizers and specifically liquid fertilizers.
To use coffee grounds and make your liquid fertilizer:
- Boil 300 to 500ml of water on a hot stove or gas.
- The more fertilizer you would like, the more water you boil.
- As the water begins to simmer, turn off the heat and add your coffee grounds to the mix – again, the more coffee grounds you add, the more potent the fertilizer will be.
- However, this will be for Ficus, so using no more than 10 to 15 grams of coffee grounds to 100ml of water is not recommended.
- Stir the grounds into the water and then let them sit in the water for a few days
- The coffee grounds and water will develop bacteria which is essential in fertilizer.
- This bacteria will break down the coffee grounds and release the essential nutrients.
In total, this process should take about 3 to 5 days.
Once completed, pour your homemade fertilizer into a spray bottle.
You can then spray your Ficus once every six weeks during the spring and summer.
How often should you use coffee grounds for your Ficus tree?
Ficus’s coffee grounds should only be used 1 to 3 times per year at most. Coffee grounds that form mulch can be used twice per year only when your Ficus is at risk of drying out. Fertilizer that contains coffee grounds should be used once every six weeks.
How much coffee grounds can be used for Ficus?
Use Only 10 to 15% of coffee grounds in Ficus compost. The remainder should consist of organic material. The same 10 to 15% should also be used for mulch that contains coffee grounds.
Use 10 to 15 grams of coffee grounds per 100ml of water of homemade liquid fertilizer.
Benefits of using coffee grounds in Ficus trees
The main benefits of using coffee grounds in Ficus include:
Cost-effective
As coffee grounds are a common household item, they can be used as a filler product in substances like compost, mulch, and fertilizer, all of which can sometimes add up.
Environmentally friendly
Coffee grounds are beneficial as instead of using hazardous chemicals in your tree, you can use a natural item such as coffee grounds.
Prevent ants
Ants hate coffee grounds.
If you keep your Ficus outdoors, coffee grounds can be used to ward off ants from coming near your Ficus.
A study back in 2018 found that while coffee grounds were not toxic to ants, they did work as an effective repellent.
Reduce soil PH
If your soil has become excessively alkaline, using coffee grounds, which have high acidic content, can be a fantastic option for reducing the PH level of your soil to a more neutral level.
Disadvantages of using coffee grounds for Ficus trees
The main drawbacks to using coffee grounds for Ficus trees are:
Acidic soil
Using too many coffee grounds can cause your soil PH level to drop.
Ficus trees do not like acidic soil, preferring a neutral PH level, so excessive use of coffee grounds will impact your Ficus tree’s ability to absorb nutrients.
Attract pests
While coffee grounds are good at repelling some insects such as ants, the organic material will often attract a lot of pests, especially if you keep your tree outdoors.
It’s not uncommon then for worms, Flies, Caterpillars, Aphids, and scale to all attack your tree that has coffee grounds.
Mold infections
If you use coffee grounds for mulch, there is a good chance you are overwatering your Ficus.
Overwatering and moisture can cause significant damage and lead to root rot and mold infections in your tree.
Mold infections are categorized by seeing white spots on your Ficus tree’s leaves.
Stunt growth
Ficus trees are usually very fast-growing.
Some studies have shown that using heavy acid ingredients such as coffee grounds can inhibit the growth of your tree.
If your tree is on the younger side, only a few years old and not mature, then using coffee ground can inhibit its growth.
Coffee grounds still contain a lot of caffeine, which can negatively affect trees when they are younger.
Other studies, however, have found caffeine has benefited some plants, such as lettuce leaf growth, but for Ficus, it’s something you want to avoid.
Ficus species and coffee grounds
So which if any Ficus species can benefit from some form of coffee grounds?
Of the 850
Almost all 850 Ficus/fig species will not benefit from coffee grounds. While having some benefits, coffee grounds are too harsh to be used frequently. Consider using coffee grounds on your Ficus only 1 to 3 times per year.
Do Ficus trees like coffee grounds – survey.
Finally, I undertook a quick survey on 20 plant paladin readers who keep Ficus trees and asked them if Ficus trees like coffee grounds:
You can see the results below:
I also asked a member of staff at my local botanical gardens on the topic, and here is what they had to say:
“Coffee grounds do make great compost. And mulch, but I would consider using coffee grounds for acidic trees such as blueberries and azaleas.”
My top picks for the gear you will need!
So like I mentioned earlier, over the past three years of running PlantPaladin, hundreds of people have asked me for my recommendations on the best bonsai gear on the market.
Having spent thousands of dollars on bonsai items these past few years and tested at least 100 bonsai-specific products, I’ve listed my favorite products below – All of which I highly recommend and think you can get great value.
They can purchase directly by clicking the link to take them to Amazon.
Bonsai Tool Set: One of the significant challenges I’ve had is finding a toolset that was not only durable but didn’t break the bank. SOLIGT has recently developed a fantastic bonsai tool set that covers all the tools you need to trim, prune, and repot your trees. – You can grab it here.
Complete Bonsai Set: Many of you will want to grow your bonsai trees entirely from scratch, but finding the varicose seeds, pots, and other items in one place can be challenging. Leaves and Sole then have created a complete bonsai set that I’ve personally used that ticks all the boxes. You can grab it here.
Bonsai wire: The number of times I’ve run out of wire for my bonsai or purchased cheap bonsai wire that doesn’t do the job is embarrassing for me to admit. After a lot of trial and error, I found that using Hotop’s aluminum bonsai wire is one of the best options on the market. This can easily be used for both indoor and outdoor bonsai. You can grab it here.
This post was written by Fehed Nicass who has been passionate about bonsai for over 3 years. He currently resides in the UK and works in sales.