What natural fertilizers work best for basil?
Written by
Benjamin Miller
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Organic fertilizers supply basil with essential nutrients, while also eliminating chemical residues that can compromise its flavor. Organic fertilizers, such as compost tea and fish emulsion, provide nutrients to plants more slowly while adding soil amendments and improving soil health. These organic fertilizers do not destroy the volatile compounds, flavonoids, and terpenes that give basil its important flavor profiles and culinary value.
Compost Tea
- Steep aged compost in water for 48 hours
- Apply as soil drench every 2-3 weeks
- Provides balanced NPK and beneficial microbes
Fish Emulsion
- Dilute 1 tablespoon per gallon of water
- Apply biweekly for steady nitrogen supply
- Promotes vigorous leaf growth without flavor dilution
Worm Castings
- Mix ¼ cup monthly into topsoil
- Slow-release nutrients improve soil structure
- Enhances water retention in containers
Banana Peel Fertilizer
- Bury chopped peels near roots
- Decomposes releasing potassium and phosphorus
- Prevents yellowing of older leaves
Application timing improves fertilizer efficacy. Compost tea should be applied at dusk or dawn, when soil temperatures are moderate. Fish emulsion should be used after watering to reduce the risk of root burn. I fertilize the basil every other week when it is growing at its peak, then reduce frequency as temperatures drop in the fall.
Soil preparation increases nutrient uptake. For new plants, incorporate worm castings into the first 2" of soil before planting. For plants already established, scratch castings into the soil surface and water thoroughly. My basil in a container exhibits denser growth and foliage when I refresh the castings once a month during the growing season.
Pay attention to plant responses to alter fertilization practices. If your plant has deep green leaves after applying compost tea, you are likely at proper nitrogen levels. Potassium deficiency is visible when the plant exhibits purple stems, and banana peels can serve as a suitable source of potassium. A yellow leaf margin suggests magnesium deficiency, which can be addressed through Epsom salt sprays.
Read the full article: How to Grow Basil Successfully at Home
