You end a banana, drop the peel right into a jar of water, and go away it to soak earlier than pouring the liquid into your houseplants. The thought sounds convincing: banana peels comprise potassium, crops want potassium, and the water ought to act as free fertilizer. However what results in that jar isn’t what many plant house owners assume.
College of California Agriculture and Pure Sources says banana-peel water releases some potassium, whereas most different vitamins stay within the peel. What appears to be like like do-it-yourself plant meals is lacking a lot of what houseplants must develop. [1]
There’s one other element price realizing. College of Maryland Extension warns that micronutrient deficiencies have an effect on many indoor crops and recommends changing these vitamins every year. Banana-peel water can not present that steadiness, regardless of how lengthy the peels sit within the jar. [2]
College of California Explains What Banana-Peel Water Comprises
Banana peels comprise potassium, a mineral crops use for water regulation, development, and flowering. When the peels sit in water, some potassium dissolves into the liquid.
College of California Agriculture and Pure Sources examined the observe in its April 2025 article Nice Gardening Myths: Half 1. The college explains that potassium is water-soluble, whereas most different vitamins stay certain contained in the peels. [1]
Meaning the water comprises some potassium, however the quantity will depend on what enters the liquid throughout soaking. There isn’t a measured fertilizer focus or balanced mixture of vitamins.
UC Grasp Gardeners say utilizing banana-peel water provides a little bit of potassium and doesn’t trigger hurt beneath the circumstances described of their steering. They suggest composting the peels afterward, fairly than throwing away the vitamins left behind.
The Vitamins Your Houseplants Are Nonetheless Lacking
Potassium is simply one of many vitamins crops want. Nitrogen helps leaves and stems, whereas phosphorus helps with root development and power switch. Calcium, magnesium, iron, manganese, and zinc additionally play roles in plant improvement.
College of Maryland Extension identifies micronutrient deficiencies as a priority for a lot of indoor crops. Its houseplant fertilizer steering recommends replenishing micronutrients every year with a fertilizer containing these components or an appropriate compost. [2]
The college additionally factors to magnesium loss via watering. As water passes via potting soil and drains from the container, some dissolved vitamins can go away with it.
Banana-peel water can not substitute that misplaced nutrient steadiness. Including potassium to a pot doesn’t assure that nitrogen, phosphorus, magnesium, or micronutrient wants have been met.
Why Extra Fertilizer Can Make a Houseplant Worse
Yellowing leaves, brown suggestions, or gradual development could make a houseplant look hungry. However these signs can even come from poor drainage, overwatering, inadequate gentle, or broken roots.
College of Illinois Extension warns towards fertilizing crops that aren’t in lively development. Houseplants use fewer vitamins when development slows, and extra fertilizer can burn roots. [3]
Its steering recommends fertilizing most houseplants not more than as soon as each one to a few months between March and September. Throughout winter, many indoor crops want little or no added fertilizer, relying on their rising circumstances.
College of Maryland Extension additionally warns that extra fertilizer can create salt buildup in potting soil and produce weak, stretched development. [2]
A plant with yellow leaves might have a change in watering or gentle fairly than one other nutrient therapy. Including banana-peel water with out figuring out the trigger doesn’t deal with these issues.
What to Use As a substitute of Banana-Peel Water
Select a houseplant fertilizer containing nitrogen, phosphorus, potassium, and micronutrients. College of Maryland Extension recommends merchandise labeled for indoor crops, used on the focus specified on the bundle. [2]
College of Illinois Extension lists 10-10-10, 5-10-5, and 10-20-10 as fertilizer choices. It additionally advises flushing potting soil with water each 4 to 6 months to take away amassed salts. [3]
Compost the banana peels as an alternative of soaking them. College of California Agriculture and Pure Sources recommends composting to utilize the vitamins left within the peels. [1]
Have you ever tried banana-peel water in your houseplants, or do you utilize common fertilizer?
Sources:
[1] College of California Agriculture and Pure Sources —
Nice Gardening Myths: Half 1, April 13, 2025.
https://ucanr.edu/web site/mgsmsf/article/great-gardening-myths-part-1
[2] College of Maryland Extension —
Fertilizer for Indoor Vegetation, up to date March 10, 2023.
https://www.extension.umd.edu/useful resource/fertilizer-indoor-plants
[3] College of Illinois Extension —
Houseplants: Care.
https://extension.illinois.edu/houseplants/care
