by Erin Marissa Russell
You may have heard the gardening tip about putting coffee grounds in your garden, but this technique should only be used in a specific situation. Coffee grounds are acidic, and if you put them on plants that like neutral or alkaline soil, they won’t be good for your plants at all. Use coffee grounds with plants that crave acidity to change the pH level of your soil.
In this article, we’ve listed commonly grown plants that like coffee grounds along with a few that don’t. This is not a comprehensive list, of course, so if you’re curious about whether a plant in your garden likes coffee grounds, just do a bit of research to see whether the plant craves acidity. It’s a good bet to use coffee grounds with acid-loving plants. If you aren’t sure about a particular plant, it’s best to err on the side of caution and save your coffee grounds for plants that will really thrive with them.
Plants That Like Coffee Grounds
Norfolk Island Pine
A Few Plants That Don’t Like Coffee Grounds
Tips for Gardening with Coffee Grounds
- Surrounding your acid-loving plants with coffee grounds is one way to keep them safe from slugs or snails. The mollusks won’t be inclined to crawl over the abrasive grounds, so they work as a barrier around your plants.
- Some gardeners report that using coffee grounds in the garden is one way to keep the neighborhood cats from digging in your carefully tended flower beds or using them as a litter box.
- Only use cooked coffee grounds that have already been used in your garden. Uncooked coffee grounds won’t give you the same benefits.
- Dilute coffee grounds with water before using them as a liquid fertilizer. The undiluted coffee grounds contain lots of caffeine (unless they’re decaf), and caffeine can be harmful for plants.
- Coffee grounds contain lots of nitrogen, making them a great ingredient for compost. By composting your coffee grounds, you can use them all throughout your garden. Just make sure that the coffee grounds make up no more than 20 percent of your compost.
- If you’re using too much coffee in the garden, you’ll see some of these negative effects: fungus growth, too much moisture in the soil, or stunted plant growth. Stop using coffee on plants that are showing these signs, and reduce your usage on other plants.
- Daily or even weekly treatments with coffee grounds will be too much for even the most acid-loving plants. A safer schedule is to use coffee grounds on your plants about once every six weeks or so. If you’re using liquid coffee on your plants, keep treatments to once every two or three weeks, and make sure the coffee you use is diluted enough not to harm your plants.
- Don’t use too much when you give coffee grounds to your plant. About a tablespoon spread in a thin layer on the soil around the plant is plenty. You want just enough so that the soil around the plant is covered with a thin layer of coffee.
- Your plants will absorb nutrition better from the coffee grounds if you water the plants right after giving them a coffee treatment.
- Don’t use coffee on young plants or seedlings, even if they’re acid-loving. Instead, wait until the plants are mature and established before starting them on coffee treatments.
- You can mix coffee grounds with mulch to make a nutritious mixture for your plants. But you’ll need to make sure you don’t use too much coffee. One part coffee to three parts mulch is a good ratio to use.
- When you’re making coffee that will eventually be used in your garden, it’s important that you use unbleached coffee filters. After all, you don’t want the bleach to make it to your plants and garden soil.
- Coffee grounds work especially well in gardens where the soil texture needs improvement. Even if your soil is heavy clay or chalky, coffee grounds will help to aerate the soil and make it a more hospitable home for plants. Coffee grounds work similarly to sand in this way, except they’re packed with nutritious nitrogen for your plants.
- People aren’t the only ones who love coffee. Worms will be attracted to your garden if you start using coffee on your plants, and as you probably know, worms are a blessing for a garden.
As you’ve learned here, using coffee in the garden can be a real benefit. However, you need to know just how to use coffee: how much to give plants, which plants like coffee, and how often to use it. All those questions were answered here, so you should be prepared to give the acid-loving plants in your garden coffee treatments that will help them thrive and grow healthy and strong.