Gardeners put coffee grounds tomato plants to add nitrogen and organic matter to their soil. The grounds break down over time and release nutrients that help your tomatoes grow. You get strong stems and dark green leaves from this free garden resource.
I tried two methods with my coffee grounds over the past five years. The first year I spread fresh grounds straight from the pot around my plants. They formed a crusty layer that repelled water and grew mold. The next year I composted the grounds first and got much better results with my tomatoes.
Coffee grounds contain about 2% nitrogen by volume. You also get small amounts of potassium and phosphorus in the mix. This makes grounds a useful slow release coffee grounds garden fertilizer for your tomato beds.
Many gardeners worry about coffee making your soil too acidic. Used coffee grounds test close to neutral on the pH scale. Fresh grounds run more acidic but most of that acid washes out when you brew your morning cup.
The organic matter in coffee grounds does more than feed your plants. It helps clay soils drain better and sandy soils hold more water. Earthworms love coffee grounds and will work them into your beds over the course of a few weeks.
Coffee grounds work well as part of a larger organic tomato fertilizer plan. Mix them with other compost like dried leaves and grass clippings. This blend gives your tomatoes a wider range of nutrients than any single item can provide.
I now add my coffee grounds to a compost bin and let them sit for two to three months. This method avoids the mold problems I had with fresh grounds. The finished compost spreads nice and crumbly around your tomato plants without clumping up.
Keep your layers thin if you apply grounds right to your garden beds. Spread no more than half an inch at a time and mix it into the top few inches of soil. Thick layers compact and block water from reaching your plant roots.
You can also brew a weak coffee ground tea by soaking used grounds in water for a night. This liquid gives your tomatoes a quick nitrogen boost during heavy fruit set. Use it once every two weeks at most so you do not over feed your plants.
Your local coffee shop may give you free grounds if you ask. Many baristas save their used grounds for gardeners to pick up. This gives you a steady supply of free fertilizer all season long without spending a dime on store bought products.
Read the full article: Companion Planting Tomatoes: Proven Plant Pairings
