These are the maximum dosages I would recommend for fertilizing fruiting bananas with 10-20-20. Also, I recommend that when it is economically feasible for you -- switch to something with a 2:1:3 (e.g., 10-5-15, 20-10-30) or a 4:1:6 (e.g., 12-3-18) ratio.
- Very Young Plants, TC's. These have 1 inch or less diameter base, with little or no corm (bulb) development. Dosage: 3/8 teaspoon per gallon of water every watering.
- Young Plant in 2 gallon pot. This has a diameter of about 1.5 inches or more. It might have been a TC that has been successfully grown for a couple of months, or a "pup" with at least a tennis-ball size corm that has been cut off a mother plant. The pstem height (not counting leaves) will be 12 to 18 inches or more. Dosage : 3 tablespoons per month, diluted in enough water to reach the roots.
- Plant (not juvenile) in 10 to 20 gallon pot, or in the ground with a similar amount of root space. This plant has at least a 3 or 4-inch diameter base. Dosage: 3/8 cup per month, diluted in enough water to reach the roots.
- Plant in ground with significant root space; i.e., 1/2 to 1 cubic yard of root volume. Maximum dosage: 9/8 cup per month, diluted in enough water to reach the roots.
- Hydroponics -- Only If The Product Does Not Contain Urea Nitrogen. Dosage (regardless of plant size): 1.5 Tbs per 6.5 gallons of water.