Coffee grounds are rich in crucial nutrients that all plants love, and lemongrass is one of them. So sprinkling your used coffee grounds in your pots of lemongrass can only do good for them.
But many people with herbal or edible gardens still wonder: are coffee grounds good for lemongrass?
Also, check: Are Coffee Grounds Good for Hydrangeas?
Why You Should Use Coffee Grounds as Fertilizer
Coffee grounds can be beneficial for both potted and in-ground plants. Since lemongrass typically prefers hot climates such as in Wisconsin or Virginia.
If you’re not from any of the places with hotter climates, adding coffee grounds to your lemongrass garden could give them a boost.
Also Read: Why Is My Lemongrass Leaves Turning Yellow?
Gives Your Plant Plenty of Nutrients
- The main reason gardeners use fertilizer is to enrich the soil with essential nutrients. Plants need a variety of different minerals to thrive, including nitrogen, phosphorus, and potassium.
- Nitrogen is responsible for healthy leaves, making it a valuable nutrient for grassy plants such as lemongrass.
- Phosphorus is responsible primarily for fruit and flower growth, while potassium helps to support a plant’s overall health and resilience.
- Most premixed soils will offer an NPK value that will tell you the ratio of nitrogen (N), phosphorus (P), and potassium (K) present in the bag.
- Since most people grow lemongrass for its citrus-flavored stalks, they need soil containing more nitrogen than phosphorus or potassium.
- Using nitrogen-rich fertilizer can help your lemongrass plants to grow faster, taller, and greener. However, you don’t necessarily need to use store-bought fertilizer to enrich your soil.
- Old coffee grounds contain around 2% nitrogen by volume, making them a cost-effective way to introduce extra nutrients into your plant’s environment.
- Grounds also contain smaller amounts of other essential and trace nutrients such as calcium and magnesium.
Check out: Why Is My Lemongrass Turning Red? [How to Save]
Improves Soil Drainage
- Lemongrass is a tropical plant, and as such, it needs plenty of water to survive.
- However, if you have dense or clay-rich soil, water may not be able to flow freely. It will get trapped around the root system of your plant.
- Such a damp environment can lead to a range of health issues, including fungal disease, root rot, and more.
- You can reduce your risk of moisture-related health issues by giving your plant loose, aerated soil.
- Many people choose to improve filtration by adding media such as peat moss or perlite. Coffee grounds can also help to improve soil consistency in addition to providing essential nutrients.
- When you add coffee grounds to the soil, you will eventually notice clumping that allows for water to trickle freely past your plant’s root system.
- As bacteria in the soil start to decompose the coffee grounds, they create dense, organic humus substances. These byproducts aggregate the surrounding soil, creating clumps.
Read: Growing Lemongrass in Pots
Ward off Pests, Fungi, and Disease
- The smell of coffee grounds can help to ward off unwanted pests such as ants, snails, and aphids from attacking your plant. Coffee can also help to discourage common fungal diseases.
- Coffee grounds have hard, abrasive surfaces which slugs tend to avoid. The grounds also inhibit the appetites of various insect species.
- Caffeine is a natural defense against predators and is found in plants such as coffee beans.
- Even once the bean is harvested and processed, the remaining caffeine content can prove fatal to certain bug populations.
- Caffeine works as a pesticide by disrupting an insect’s nervous system. Once a bug stops producing essential enzymes, it may undergo paralysis and then death.
- The compound is less fatal for bugs such as mosquitos. However, while it may not cause death, it can result in lasting reproductive harm that can reduce a mosquito population.
- Adding coffee grounds to your soil can help to protect your lemongrass plant against a wide variety of pests, thus leading to a bigger, healthier harvest.
Read: How to Grow Lemongrass From Stalk
Save Money and Reduce Waste
- Store-bought fertilizers can be pricey, so making your own may help you to save on garden maintenance.
- By using leftover coffee grounds, you save on buying an expensive container of nitrogen-rich chemical fertilizer.
- Using old coffee grounds can also help you to cut back on waste and reduce your carbon footprint.
- Reusing and recycling grounds means less material making its way to landfills. Less organic matter in landfills also cuts back on methane byproducts that harm the atmosphere.
Check: Is Lemongrass a Perennial?
Are Coffee Grounds Good for Lemongrass?
- Coffee grounds make a particularly good choice of fertilizer for leafy plants, including grasses such as lemongrass.
- These types of plants need plenty of nitrogen for healthy green leaf growth. Otherwise, they will not be able to produce the chlorophyll they need for healthy photosynthesis.
- This type of nutrient deficiency may stunt the growth of an otherwise healthy plant. It can even spell a death sentence for young or struggling lemongrass plants.
- Coffee grounds are rich in nitrogen, which is key to a healthy crop of lemongrass. It makes an ideal fertilizer for those looking to promote leaf and stalk growth over flowering or fruiting.
The Risks of Using Coffee Grounds
While there are plenty of good reasons to add coffee grounds to your soil, there are also some risks. Coffee grounds may lead to issues such as:
- An acidic pH that falls below the desired range of 6.5 to 7.0
- High nitrogen levels may stunt fruit and flower growth in nearby plants
- High caffeine levels can kill young or delicate plants
- Earthworm death, which may impact soil quality
- Fewer healthy soil microbes due to antibacterial activity
While coffee grounds might be able to improve soil composition and quality, remember that they can also impact long-term plant growth.
Check out this post: Is Lemongrass Safe for Dogs? Can Dogs Eat Lemongrass?
How To Use Coffee Grounds
There are two main ways that you can add coffee grounds to lemongrass plants to encourage healthier growth.
Apply Grounds Directly
- Perhaps the easiest way to use coffee grounds as fertilizer is by adding them directly to the soil.
- If you are transferring your lemongrass plant to a new pot, you can mix coffee grounds with your potting soil in bulk before potting.
- It’s best to add grounds in a one-to-four ratio. This means that coffee grounds should make up about 25% of your soil composition.
- If your lemongrass is already in a pot or in the ground, you can also sprinkle coffee grounds around the soil’s surface.
- Each time that you water your lemongrass, nutrients will leach from the grounds and into the soil below, making them accessible to your plant’s root system.
- Adding coffee grounds on top of the soil instead of mixing them in may be the best choice for gardeners who are battling pests.
- Coffee grounds can deter harmful insects and fungal diseases from latching onto your lemongrass plant.
- With more exposed grounds around your plant, pests are more likely to steer clear when they smell the potentially toxic compounds found in coffee.
- Like most granular fertilizers, direct application of coffee grounds works best for potted lemongrass. Nutrients may not penetrate deep enough into the soil for in-ground plants.
Read: How Do You Keep the Lemongrass Plant Healthy?
Create a Liquid Solution
- If you want to fertilize lemongrass growing in the ground, you may want to opt for a liquid solution.
- Liquid fertilizer is easy to apply and can distribute essential nutrients deep into the soil, supporting healthy root growth.
- You can turn coffee grounds into a liquid fertilizer by soaking them in a bucket of water for about a week.
- Nutrients such as nitrogen will leech into the water over time, creating a homemade fertilizer mix that’s ideal for leafy plants like lemongrass.
- Once your liquid fertilizer is ready, you can apply it to the soil. Either pour a small amount over the surface and allow it to drain thoroughly, or use a dedicated fertilizer sprayer.
- A sprayer will typically give you more control over the amount of fertilizer you add to a given area. It also ensures that you have consistent, even coverage throughout your soil.
- If you have extra fertilizer left over after treatment, you can save it to use later.
- Ensure that you place the fertilizer in a tightly sealed container stored away from heat or light.
- Keep all fertilizer out of reach of children or pets, as your mixture may contain harmful or even toxic chemicals.
- If you or someone you know accidentally ingests fertilizer, contact poison control immediately.
Other Ways To Encourage Growth
If coffee grounds don’t work for your lemongrass plant, there are plenty of other tricks you can try to encourage healthy growth:
- Offer plenty of direct sunlight
- Keep soil moist, but not oversaturated
- Keep soil pH close to neutral, or around 6.5 to 7.0
- Add compost to your soil
- Try other natural, nitrogen-rich fertilizers such as worm castings
By promoting a rich, supportive environment, even novice gardeners can grow a healthy and hardy lemongrass plant to spice up their next meal.
Also, you may like some more Gardening Tutorials:
- How Often Do You Water Lemongrass Plant
- How Do You Make Lemongrass Grow Tall?
- How to Make Lemon Grass Mosquito Repellent [Some Useful Tips]
- Why Are My Lemongrass Leaves Wilting? [How to Care]
- How to Care For a Lemongrass Plant [Useful Tips]
- What to Plant With Lemongrass
- How To Grow Lemongrass From Seed Indoors
- How to grow Lemongrass From Cuttings
If your lemongrass isn’t growing as well as you’d hoped, you may want to consider adding coffee grounds to your soil.
Coffee grounds can act as a nutrient-dense fertilizer that helps leafy plants like lemongrass to thrive. They can also improve soil drainage and scare away pest populations. Reap the benefits of coffee grounds and enjoy your healthy herbs.
I’m Elsa, and I love gardening. I started GardeningElsa.com as a resource for other gardeners, and I offer expert advice on gardening topics such as plants, flowers, herbs, and vegetable gardening. On my website, I share my latest tips and tricks for creating beautiful gardens. When I’m not working on my website, you can find me in my own garden, tending to my plants and flowers. Read more about me.