Coffee grounds are a popular addition for gardeners. Many believe adding coffee grounds to potting soil, or their garden helps pepper plants grow and yield more.
Coffee grounds do contain nutrients that can benefit pepper plants. However, they must be applied carefully to have any benefit.
How Can Coffee Grounds Help Pepper Plants?
Coffee grounds contain essential nutrients pepper plants need to develop and produce bountiful yields of bright green, yellow, or red peppers.
Coffee grounds have phosphorous, magnesium, and potassium—the three major minerals plants need to grow.
In addition, they contain some nitrogen, which can be fixed once in the soil and used by plants for growth.
Finally, in addition to the main nutrients, coffee grounds contain some elements that plants require, such as:
If used correctly, the combination becomes a very effective fertilizer.
How NOT To Use Coffee Grounds On Pepper Plants.
The temptation is to simply spread the coffee grounds over the garden around the pepper plants as mulch and to let nature take its course.
Certainly, coffee grounds can be used as a top cover to retain water and keep soil from drying out.
However, most of the benefits of the application will be lost, and unless your family drinks astronomical amounts of coffee, there are easier ways to find mulch for ground cover.
Put The Coffee Grounds In The Compost Heap.
Coffee grounds are organic materials and must be decomposed or broken down into a form for their nutrients to be released that the roots of the plants can absorb and make available for pepper plants.
While this can be done directly in the garden’s soil, the benefit will only be gained slowly, perhaps over several years.
The faster approach would be to place the coffee grounds in your compost heap, along with all the other lawn clippings, vegetable waste, and garden refuse of the household.
The hot, damp environment of the compost heap will help speed the process and break down the coffee grounds quite quickly.
If you decide to place coffee grounds in the compost heap, be sure that they make up at most 20% percent of the mass of the pile at any one time.
The acid in the coffee grounds can damage the organisms that break down organic material into humus if it is too concentrated.
Make A Fertilizing Liquid With The Coffee Grounds.
Another option to help get nutrients out of the coffee and into the garden quickly is to make a fertilizing liquid (often called “tea”) out of the used coffee grounds.
The easiest way to do this is to simply run a second pot of water through the coffee maker and reuse the spent grounds.
Let this second pot of weaker coffee cool to room temperature before pouring it on your pepper plants. One or two applications a month should be more than ample.
Do not make a fresh pot of coffee and pour that on the plants. The coffee contains acid and other harsh chemicals, and using “first-run” coffee grounds will harm your plants.
Use Very Small Amounts of Coffee Grounds Dug Into The Soil.
You can dig some finely ground coffee grounds directly into the soil. This requires care, as coffee grounds retain water. This excess moisture can leave a plant waterlogged and unable to absorb more nutrients from the soil.
In such cases, the roots will begin to rot. The plant will turn yellow and eventually die. For peppers being started indoors in containers, the ratio ought to be 1/4 of a cup of coffee grounds to 4 cups of potting soil or dirt, which makes a 1:16 ratio. A similar ratio might work in the garden.
The better practice would be to compost the coffee grounds first or to use them to make a fertilizing liquid and then compost them.
What Kind Of Coffee Should You Use?
Most varieties of ordinary coffee, whether regular or decaffeinated and most grinds, should work perfectly well for the garden. The exact brand or bean is irrelevant.
Avoid using artificially flavored coffees. Many rely upon chemicals to provide the flavor that might harm the plants.