Many people swear by coffee grounds as a wonderful pick-me-up for indoor houseplants, in the same way, that the coffee itself perks up the plant owners.
The truth is that coffee grounds can be beneficial for fertilizing indoor houseplants, but they must be used correctly. It can also do more harm than good if the coffee grounds are misused.
This article will help turn those old coffee grounds into a helpful tonic for your houseplants.
How Do Coffee Grounds Help Indoor Plants?
Coffee grounds contain all of the essential nutrients plants need. Coffee grounds are rich in the following:
These three major nutrients that plants require are found in every sort of fertilizer. Coffee grounds are also rich in nitrogen.
Once in the soil, that nitrogen can be fixed and used by the plant for growth. In addition to the main nutrients and nitrogen, coffee grounds are rich in the trace elements plants need and have lots of copper, zinc, and calcium.
All of the nutrients combined can make a very effective fertilizer.
How NOT To Apply The Coffee Grounds
The temptation might be simply to spread the coffee grounds over the dirt around the houseplant and use it as mulch.
However, putting the damp coffee grounds down on the container right next to the plant will not help the plant and may be harmful.
The coffee grounds right out of the coffee pot will be extremely damp and still contain plenty of leftover water. The roots of any plant receiving too much water will become over-saturated.
The excess water won’t be absorbed but will remain in the soil around the plant. Over time, the plant will begin to show signs of root rot. If completely untreated, the plant will develop root rot and possibly die.
Using Coffee Grounds With Potting Soil
If you wish to use coffee grounds directly in your potting soil, don’t dump a considerable amount of grounds into the plant. Instead, mix them into the potting soil or dirt before use.
For example, for every 4 cups of soil, use 1/4 cup of coffee grounds and mix the two. The water will leach out of the coffee grounds over time and into the surrounding potting soil, releasing the nutrients locked into the coffee grounds.
To use coffee grounds on a houseplant already potted, take one or two teaspoons of grounds and gently work them into the potting soil around the plant in the pot.
Be sure to distribute the grounds evenly around the plant and to work them into the soil well. This will prevent the grounds from concentrating their water in one spot.
Using Coffee Grounds To Make A Fertilizing Liquid
One alternative method to using coffee grounds effectively is to make a fertilizing liquid from them. Such liquids are called, perhaps confusingly, “teas.”
The liquid will fertilize the houseplant without leaving too much water as a residue in the soil.
The best way to make a fertilizing liquid from coffee grounds is just to use them to brew a second pot of coffee.
Avoid the temptation to pour freshly brewed coffee on the plants. Strong coffee is too harsh for plants and will do harm. Instead, the second brewing of used grounds will deliver the right amount of nutrients to the plants.
Of course, you shouldn’t pour scalding hot water onto the houseplants either. After brewing the second pot of coffee using the grounds, let the pot cool to room temperature.
What Kind Of Coffee Should You Use?
Simple coffee, either decaffeinated or regular, can be used to make a fertilizing liquid or coffee grounds for fertilizer and mulch.
Also, the exact type of bean or brand does not matter. You should avoid flavored coffee as such varieties can contain chemical additives harmful to plants.
More On Using Coffee Grounds
- How To Use Coffee Grounds In The Garden – Adding coffee grounds has many garden benefits for compost, growing mushrooms, fighting slugs, and more.
- What Plants Benefit From Coffee Grounds – For acid-loving plants coffee grinds work well as a soil amendment.