It’s exciting to reuse kitchen leftovers in the garden. However, in most cases benefits aren’t backed by scientific reports.
Though coffee grounds are packed with essential macro and micronutrients that can benefit your houseplant, it is not advised to apply used coffee grounds directly on plants.
Does peace lily plant like coffee grounds?
Coffee grounds have 2 percent of nitrogen, 0.3 percent of phosphorus and potassium each.
Nutrients in coffee grounds aren’t readily available for plant to intake. They need to be decomposed.
Yes, nutrients and minerals in leftover coffee grounds can benefit peace lily plant to some extent. But, you should use it with caution.
You can add coffee grounds to compost, use it as mulch along with organic mulch and its liquid solution can be used to fertilize peace lily plant.
Coffee grounds use for plants are surrounded by myths and facts.
Coffee grounds aren’t good for peace lily plants – Is it true?
An expert gardener carried out a small experiment to check benefits of coffee grounds. He applied a thick layer of fresh coffee ground around a vegetable plant.
After few weeks, the crop yield showed no positive impact. Worse part is, leaves started turning yellow, plant experience slow growth and few younger plant died.
Why plant leaves turned yellow after using coffee grounds?
As you know, caffeine housed in coffee grounds inhibits seed germination and its antibacterial ability can kill some earth worms who’re working to make growing soil fertile.
So, should you stop using coffee grounds for peace lily?
I have another report from Dr. Chalker Scott, according to her you can USE COFFEE GROUNDS BUT WITH CAUTION.
Remember this: Using coffee grounds in higher quantity can damage your crop or houseplant.
Instead, Dr. Chalker Scott recommends adding coffee grounds to compost, but not more than 20 percent of total compost volume. (Source)
Nutrients Requirement for Peace Lily Plant
A balanced fertilizer with 20-20-20 NPK ratio will be enough to thrive peace lily plant.
Most busy indoor gardeners don’t fertilize this plant. To your surprise, their plant does well.
But, if you want your peace lily to bloom, then you must use fertilizer thrice in growing season.
Remember, too much fertilize can result in brown or discoloured foliage.
The reason why I recommend fertilize your peace lily plant is, due to regular watering growing soil lose micronutrients. Also, older leaves start to fall. To boost plant growth, you must use fertilizer.
A liquid fertilize once after 6 weeks will be enough to bloom peace lily plant.
If you’re using organic fertilizers that are rich in nitrogen, then you must reduce nitrogen percentage in your liquid fertilizer.
- Nitrogen is responsible for green foliage and plant growth, but excess use can stop peace lily plant from blooming.
- When you apply phosphorus rich fertilizer, it will help the plant to produce blossoms and strengthen root system.
- Similarly, potassium is essential for food production, contribute in promoting roots and balance water pressure in plant cells.
Read more on fertilizing peace lily plant here.
How to Use Coffee Grounds for Peace Lily Plant?
As a gardener it might be confusing, when some gardeners say to use coffee grounds, while other abandon its use.
Now, a question arises. Do peace lilies like coffee grounds?
Let’s me put this in simple words.
Coffee grounds can’t make your peace lily plant thrive instantly. As mentioned earlier, nutrients in coffee grounds need to be decomposed which may take months to be used by plant.
However, you can use coffee grounds to fertilize peace lily in two ways as discussed here by University of Arizona.
- You can add used coffee grounds to compost. (not more than 20 % of total compost volume)
- Mixed with organic mulch
Water soluble elements in coffee beans are transferred to liquid while making coffee and along with antibacterial, antifungal properties, insoluble elements are left with used coffee grounds.
When you add coffee grounds to compost, its antibacterial ability can kill earth worms that are working on decomposing waste. This is why Dr. Chalker recommended limiting its use not more than 20 percent of your compost.
Now, you don’t have to run towards coffee vendors to bring bags of used coffee grounds. Instead, you can add kitchen leftover coffee grounds to composting bin.
Also Read: Are Eggshells Good for Peace Lily?
Compact nature of coffee grounds will block water and air flow, if you add thick layer of coffee grounds around peace lily plant.
Don’t use pure coffee grounds as mulch.
Instead, you must add half inch of coffee ground with 4 inches of organic mulch.
Also Read: Can a Peace Lily Grow in Water?
Can you use coffee grounds liquid to fertilize peace lily plant?
Add some water to a boil and boil it on low flame.
Off the gas stove, when water starts boiling.
Add coffee grounds to this water bowl and allow it to cool.
Strain coffee grounds and use the obtained liquid to fertilize your peace lily plant.
Note: This coffee ground liquid can’t replace a balanced liquid fertilizer. Use this homemade coffee ground liquid once in a month.
Also, don’t skip your water cycle if you’re using liquid fertilizer.
Also Read: How Much Light Do Calla Lilies Need?
Myths of Using Coffee Grounds for Peace Lily Plants
Few gardeners exaggerate the benefits of coffee grounds, which are just myths.
Coffee grounds can improve pH – Myth
Use of coffee grounds can’t improve pH of the soil. An experiment carried out by University of Arizona, states that coffee grounds are mildly acidic to alkaline.
As the months pass, when you add fully decomposed coffee grounds, it won’t be able to be in acidic state.
Repel Pests – Myth
Freshly used coffee grounds can attract pests and spread infestation.
It can’t stop or repel snails. (Source)
Best mulching agent- Myth
As mentioned, using pure coffee grounds can block air and water movement.
Instead, you must mix organic mulch (four inches) with coffee ground (half inch).
Check this out: How Long Does a Peace Lily Plant Live?
Growing tips for peace lily plant
Peace lily is an easy to go plant that doesn’t require much attention.
This houseplant is best for lazy gardeners.
However, to have a thriving peace lily plant you must provide few essential elements like water, sunlight and well-drained soil.
- Soil: Well-drained fertile soil that retains moisture is best for peace lily plant.
- Water: Avoid overwatering. This houseplant doesn’t like to sit in excess water. Allow the growing soil to dry between watering cycles. Overwatering results in peace lily root rot.
- Sunlight: If you’re growing peace lily indoors, putting in outside will do wonders. It likes bright indirect sunlight. Harsh sunlight can damage its leaves.
Apart from this, you need to fertilize peace lily plant once after 6 months.
Can I water peace lily with coffee?
You must know this, adding hot coffee can kill your plant.
Yes, you can add liquid fertilizer obtained from coffee grounds.
But, you count it as watering your peace lily plant.
How often to put coffee grounds on peace lily?
Add coffee grounds once in a month.
If you’re using any other home available fertilizer, then check its NPK value. This will help to reduce or increase NPK value of your liquid fertilizer.
Peace lily plant grows good even if you add liquid fertilizer once in a month. Actually, they don’t need much.
However, when you fertilize peace lily plant it does bloom and foliage turn dark green with adequate sunlight.
But, are coffee grounds good for peace lily plant?
There is no direct answer for this. You shouldn’t use coffee grounds directly on peace lily plant it won’t help. Instead, it can attract infestation.
Best way to use coffee grounds is to add leftover to compost bin. That too should not excess 20 percent of total compost volume.
I don’t think coffee grounds are great way to fertilize peace lily plants, but yes you can use it in compost as green item.
Khaja Moinuddin, a computer science graduate, finds joy in gardening and homesteading. Join him on this blog as he shares his experiences in homesteading, gardening, and composting