Coffee grounds for plants have more valuable properties than you think. Coffee contains a lot of micronutrients and is used as an organic fertilizer for plants. But you can not just pour it into the soil, it is necessary to know all the nuances of such fertilizer.
This approach makes it possible to saturate the soil with useful substances without chemicals. So don't rush to throw away the coffee grounds after drinking the beverage since they can also be used for the benefit of your plants. In this article, we've put together a complete guide to using coffee grounds for gardening purposes.
Is Coffee Good for Plants?
Yes, and yes! Coffee beans are rich in minerals such as magnesium, calcium, phosphorus, nitrogen, and potassium. Phosphorus and potassium improve yields, and nitrogen is involved in photosynthesis, which helps plants grow faster. Ground coffee is excellent for both house and garden plants.
Ways To Use Coffee Grounds in the Garden
Gardeners began to use coffee grounds in planting quite recently. And only a few people know about this unique and useful substance. We have compiled a list of the best ways to use ground coffee to benefit your plants.
Using Grounds as a Natural Nitrogen Fertilizer
If your plants need nitrogen fertilizer for garden, have a look at coffee. Coffee grounds are valuable as a fertilizer for plants containing nitrogen and other elements. In its nitrogen content, coffee grounds are equal to grass clippings.
It's hard to overstate the importance of nitrogen for soil, especially for plants, for which nitrogen is a vital element. Nitrogen leads to faster plant growth, strengthens the stem, and helps in chlorophyll production. Therefore, natural nitrogen for plants becomes an excellent fertilizer. Used coffee is also an excellent source of nitrogen for composting. It contains about 2% of this element, and with the right proportions, you can make great compost.
Remember, If you use coffee grounds as fertilizer, it is essential to follow proper watering techniques. The soil must dry out well to prevent the appearance of mold.
Using Coffee Grounds as Mulch
Coffee grounds are also used for mulching to prevent the soil from drying out, protect against pests, and improve soil quality. You can mulch both houseplants and garden plants in the open ground. Cover the soil around the plant's trunk with well-dried coffee grounds and water abundantly. Each watering will release nitrogen from the coffee grits and penetrate into the soil with water, soaking the plant's root system, thereby strengthening it and protecting it from pests.
Composting with Coffee Grounds
Compost is the most effective organic fertilizer for plants. It is suitable for the orchard or vegetable garden and for nourishing house plants.
Ground coffee is added to compost to speed up the process of maturation. They act as nitrogen compounds that start an exothermic reaction in the compost heap, which warms it up considerably and thereby ripens the compost much more quickly.
How to Compost Coffee Grounds
Start composting by calculating the right amount of coffee grounds and other ingredients. You can often vary the composition, but an optimum mixture is 50 % coffee grounds, 30 % straw, and 20 % leaves.
Prepare a compost pit or large tank, which should be placed in the most protected place from rain and wind.
Place coffee grounds, straw, and leaves or dried grass in the same pile.
Coffee grounds should be well mixed and covered with fertile soil.
Water the compost to make it a little wet and make a few holes to create a microclimate inside.
Your compost will be ready in 3-4 weeks. After that, it can be used as a fertilizer for houseplants and garden plants.
Coffee Grounds as a Pesticide
Coffee grounds can be used as a perfect protector against pests. Ants, snails, slugs, and many other insects do not like coffee grounds, which means they will avoid your garden beds. In the opinion of many gardeners, coffee can also kill the larvae of pests, particularly mosquitoes and garden bugs. Coffee grounds are not as effective as insecticides, but one of the clear advantages is their non-toxicity.
What Plants Like Coffee Grounds
As an organic nutrient, coffee grounds are suitable for most plants. However, since coffee slightly acidifies the soil, it is beneficial for roses, hibiscuses, begonias, and other plants prefer substrates with an acidic or slightly acidic reaction.
Before diving into the specifics, take a look at this visual guide to some popular plants that thrive with coffee grounds—it might surprise you!
What Vegetables Like Coffee Grounds?
Coffee grounds as a fertilizer can be used when growing vegetable crops such as potatoes, cucumbers, peppers, carrots, radishes, and beans. Root crops need magnesium and potassium, while nitrogen is indispensable for green crops.
Onions
For non-commercial purposes, onions are advised to grow only on organic fertilizers. The main valuable component for onions is nitrogen. If you fertilize green plants, such as lettuce and spinach, with a coffee substrate, the yield will be higher due to the nitrogen content of coffee. Adding coffee grounds to soil only benefits onion and green cultures.
Potatoes
The most important period in the potato life cycle is the budding and flowering phases. The nitrogen, phosphorus, and potassium consumption reaches its peak, and the plant needs to be fertilized. This is when coffee containing these nutrients comes in handy.
Carrots
Carrots like fertile soil with a neutral pH, loose and breathable, which coffee grounds can provide. Also, carrots prefer decomposed fertilizers, so use ready-made compost with coffee grounds or humus to fertilize them.
Are Coffee Grounds Good for Flowers?
Flowers are especially fond of coffee grounds. Shrub roses and begonias root much better and develop harmoniously after feeding with coffee grounds. Such fertilization is suitable for peonies, lilies, hostas, tulips, etc.
Roses
Coffee grounds can protect rose plants from pests due to their high potassium content. After coffee treatment, the flower becomes less attractive to them. Once the grounds are put in the soil, it becomes lighter, making the airflow to the roots easier. Soil rich in nitrogen, phosphorous, magnesium, and potassium is vital when growing roses from cuttings.
Interesting fact: by fertilizing roses with grounds, you can achieve a change in the color of the flower.
Hibiscuses
Coffee grounds are an organic, non-toxic fertilizer containing all the necessary microelements for hibiscus. Feeding the plant in the spring and winter can be monthly with coffee grounds, which contributes to prolonging the flowering period.
Begonias
Begonias love the addition of phosphorus-potassium and nitrogen to the soil, so coffee is an excellent substitute for chemical fertilizers. Coffee grounds help them develop buds and inflorescences.
Which Plants Do not Like Coffee Grounds?
Some plants tolerate an acidic environment very well, but there are also those for which the acid will be poison. Plants such as sago palm, yucca, etc., will not become friends with coffee grounds.
Lavender
This plant needs an alkaline environment for growth and good flowering. For fertilization, you can use potassium products and beware of nitrogen ones. Therefore, coffee grounds are not suitable fertilizer for lavender and can lead to its death.
Orchids
Coffee grounds are too acidic for epiphytes, so their roots can rot, and mold will appear on the surface, which can attract the attention of mosquitoes. Although coffee contains enough nitrogen that orchids need, their roots do not absorb it, leading to rotting.
Rosemary
Rosemary needs fertile, loose soil with a neutral pH. The plant does not like acidic soils and overwatering, so coffee, which creates an acidic environment, will be destructive for rosemary. The plant can be nourished twice a month with mineral and organic fertilizers that create an alkaline environment.
How Often Should You Add Coffee Grounds to Plants?
You can fertilize houseplants an average of 7 to 10 days in a row, but no more, as there is a risk of over-acidification of the soil. A cup of ground coffee should be added to the compost once a week. Do not forget that before adding it to the compost, the ground should be dried to prevent mold formation.
FAQ
Do Rhododendrons Like Coffee Grounds?
Rhododendrons are not only charming but also very capricious. Coffee grounds acidify the soil, making it perfect for this flower. It is recommended to use coffee as additional fertilizer along with horn shavings. Rhododendrons are quite often attacked by root weevils. To protect them, spray the flowering shrubs with a coffee mixture.
Do Ferns Like Coffee Grounds?
The fern will not thank you for adding coffee grounds. Coffee will put too much nitrogen in the soil for the fern, stopping the plant's development. More importantly, coffee has an antibacterial effect and kills the germs necessary for the fern. Therefore, it is best to keep your fern away from coffee.
Are Coffee Grounds Good for Gardenias?
Don't worry about adding more coffee grounds to your gardenia soil; these flowers absolutely love coffee. In addition to being an excellent source of nitrogen, the acid in coffee lowers the pH of the surrounding soil, stimulating the roots of acid-loving plants such as gardenias.
Can I Put Fresh Coffee Grounds in My Garden?
It is not recommended to fertilize the garden with fresh coffee grounds. Increased humidity promotes the growth of mold spores. The coffee grounds must be dried before they are added to the soil. Dry it in the oven, and then put it into plastic bags for ease of use.
Can You Water Plants with Coffee?
Plants that like coffee grounds also respond well to watering with coffee liquid. However, it is a fairly strong fertilizer, so this watering should not be done more than once a week. To prepare the mixture, boil the coffee and pour one and a half times as much water.
