To produce juicy strawberries, this fruit plant needs regular fertilization. Even if you already added old compost while planting, you should enrich strawberry plants with slow-releasing fertilizers.
It is fascinating to use kitchen leftovers to enrich the growing soil. Coffee grounds are one such substance that goes straight into the garbage. But, as a gardener it is your responsibility to keep your surrounding clean. You can do this by reusing kitchen leftovers.
But wait!
Is it safe to use coffee grounds on strawberry plants?
Coffee grounds can be used as a green material in your compost pile. It adds nitrogen, phosphorus, calcium and other trace minerals to your compost.
But, there are many theories and claims about benefits of coffee grounds. Most of them are baseless and have no scientific evidence.
In simple words:
Best way to use coffee grounds to enrich strawberry plant is to add them to your compost pile. It takes months to break down complex compounds to plant ready nutrients.
You can also use leftover coffee grounds as mulch and mix small quantity with potting soil to improve aeration, drainage and water retention ability.
There are some claims that adding coffee grounds will benefit acidic loving plants like strawberry. But, this research states that composed coffee grounds have shown not so stable soil pH.
Can adding used coffee grounds directly to the soil increase its pH?
There are claims that this kitchen leftover can be used to repel slugs in your garden. In this write-up I’ll discuss benefits of coffee grounds for strawberries with scientific evidence.
Before that, let’s first understand essential requirements of your plant.
What Nutrients Does Strawberries Need to Grow?
Department of primary industries Australia, states using slow releasing fertilizer benefit strawberry plant regularly over a period of 3-9 months.
Strawberry plant needs essential nutrients like nitrogen, phosphorus and potassium to grow stem, leaves and to produce fruits.
However, nutritional needs of strawberry plant changes along with the growth of the plant.
In initially, days when the plant is younger a balanced fertilizer would boost root growth and leave formation. Later, when the plant is about to fruit, you should reduce nitrogen and continue with phosphorus and potassium. (Source)
Timing is the key to fertilize strawberries.
Early fertilizing may result in too dense plant, which is ideal for pests and diseases. Late fertilizing impact the yield.
Whatever the fertilizer you use, it is always recommended to add organic matter to the potting soil as it can efficiently releases nutrients into the soil.
With the regular nutrients release that enriches the soil, your strawberries have a even growth with no fertilizer burn.
What Nutrient Does Coffee Grounds Give Plants?
Though many people think left-over coffee grounds are of no use. They actually contain 2 percent of nitrogen and 0.3 percent of phosphorus and potassium.
Yes, they aren’t huge. But, for those who care about reducing wastage it is abundant.
Instead of throwing them in garbage, you have reuse kitchen leftovers to enrich your growing soil.
However, there are few false claims surrounding this soil amendment, which we will burst in this write-up.
Though they are brown in color, you can add them to composting bin as a green material. Along with brown material, within few months compound nutrients in this kitchen leftover are made readily available for your strawberry plant.
Myths on Coffee Grounds Gardening Usage
1. Adding coffee grounds to soil increases its pH – it is a myth.
University of Arizona and Washington state university claims that pH of composting coffee grounds is mildly acidic and it is not stable.
Thus, it won’t have significant impact on soil pH.
2. Coffee grounds can keep slugs and pests away – Myth
Again Washington state university study states there is no scientific evidence backing this claim. Further it has no ability to attract or repel pests.
Are Coffee Grounds Good for Strawberry Plants?
Nutrients in coffee grounds listed above aren’t readily available for strawberry plant to absorb and benefit from it.
However, when they are decomposed it can enrich the soil with nutrients as mentioned above.
If you’re not relying only on coffee grounds to fertilize strawberry plant, then it is good to use them.
But, there are gardening experts who claim that if coffee grounds used directly on plant can do more harm to them.
Again, we’ve Dr.Chalker Scott who recommends adding coffee grounds to compost pile but not more than 20 percent of total compost.
To make it simple, am putting down expert opinions in points, so you can decide whether it is safe to use coffee grounds on strawberries or not.
- There are studies that show use of coffee ground mulch on seeds showed negative impact on its germination rate. You should avoid using composed coffee grounds to germinate seeds and to enrich young plants.
- Don’t use pure coffee grounds to mulch around your strawberry plant. With its compact nature it may acts as barrier and impact plant growth. Instead, mix some organic mulch along with coffee grounds to spread around the plant.
- Avoid using fresh and hot coffee grounds on plant directly.
- Don’t think of bring used coffee grounds from vendors to enrich you garden. Coffee grounds left in your kitchen are enough to add to compost pile.
- As already mentioned, don’t use coffee grounds more than 20 percent of your total compost.
- Yes, you can use coffee ground liquid to fertilize your plant once in a month.
- Adding coffee grounds won’t have significant impact on soil pH.
(Read on this Why Are My Strawberry Leaves Turning Red?)
How to Use Coffee Grounds for Strawberry Plant?
Right use of coffee grounds can benefit your plant and wrong use can ruin their growth.
So, don’t skip.
Important: You should use only composed coffee grounds to amend with soil.
There are 3 ways with which you can use coffee grounds to fertilize strawberry plant.
- Add coffee grounds to compost pile. (Remember not more than 20 percent)
- Mix coffee grounds with organic mulch to spread it around the plant.
- Liquid fertilizer.
Using coffee grounds in compost
If used properly, coffee grounds can benefit your plant with essential nutrients.
Below mentioned are important points that need to be followed while adding coffee grounds to compost.
- Adding less than 20 percent of total volume of compost ensures health growth of microorganisms.
- Don’t add hot coffee grounds directly to compost bin. Allow it cool.
- Don’t add coffee grounds to vermicomposting, as it can kill earthworms in confined areas.
- Coffee grounds are green material to your compost, so you must add brown material to balance the nutrients.
- It takes several months for microorganisms to break nutritional compounds in this kitchen leftover.
Mix it with organic mulch
As already mentioned above, fine texture and compost nature of coffee grounds can interfere in air circulation and moisture around the plant, you’re recommended mixing it with organic mulch.
Spread thin layer of mulch not more than half inch around the plant and cover it with a 4 inches of organic mulch like wood chips.
Liquid Fertilizer
I personally don’t use not I recommend it.
Not because it is useless, because it takes time.
You need to add used coffee grounds to boiling water and let it cool. Strain coffee grounds and collect liquid in a jar.
Now, this collected liquid has nutrients which can be used to enrich your strawberry.
Note: Don’t rely on this liquid fertilizer for essential nutrients of your strawberry plants.
(Read on this: How often to water strawberry plant?)
When to fertilize strawberry plants with coffee grounds?
If you’ve prepare the garden bed with organic matter and compost, then you don’t have to fertilize strawberry every two weeks.
However, you should add fertilizers once per season to ensure the berries are firm and juicy.
You should add a balanced fertilizer to your gardening bed.
Note: Did you ever tried growing strawberries in hanging baskets?
Can I put coffee grounds on my strawberry plants?
Coffee grounds are packed with nitrogen and small amount of phosphorus and potassium.
But, direct adding isn’t recommended.
You either add it to compost bin or mix it with organic mulch to be used as mulching agent.
Strawberry Plant Fertilizing Tips
Adding organic fertilizers like compost and manure will ensure the plant is getting regular nutrients. Even strawberry plant prefers slow releasing fertilizers.
However, you can add store brought balanced organic fertilizer to enrich your strawberries.
- Use 10-10-10 fertilizer for optimal growth of strawberry plant.
- Follow the instruction on the fertilizer before applying it on the plant.
- Adding compost or worm castings to potting soil or preparing garden bed with organic fertilizers give essential boost for plant growth.
- Fertilize your plant once during the season. Probably in early spring.
- Don’t over fertilize your strawberry plant.
- Conduct soil test before adding fertilizers.
- Ensure regular watering after fertilizing strawberry plant.
- Strawberry plant needs 8 hours of full sunlight.
Conclusion
Coffee grounds are packed with nitrogen and other nutrients, but they aren’t readily available for the plant to absorb.
You can add coffee grounds to compost, but shouldn’t exceed 20 percent of total volume.
After decomposition, which may take months, nutrients can benefit your strawberry plants.
Though nutrients in this kitchen leftover may not seem significant or give an extra boost, but instead of throwing them you can reuse the nutrients to benefit your plant.
Don’t directly add coffee grounds to strawberry plant. Care to read above highlighted points to rightly use coffee grounds.
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