Fertilize the curry leaf for the first time each growing season in the spring, just before the plant produces new growth. Repeat the application every month until October.
Mix 1 tbsp. of 30-10-10 water-soluble fertilizer in 1 gallon of water. Water the curry leaf plant with the solution at the rate of 1 gallon for every 10 square feet from its trunk to the dripline.
Feed the container-grown curry leaf with the same fertilizer, mixed at a rate of 1 tsp. per gallon of water. Pour the solution onto the container's soil.
Apply chelated iron to the soil, as required, every other month. This guards against chlorosis.
Provide the curry leaf with a gypsum application once a month during the months that you don't apply iron. Gypsum supplies the curry leaf with calcium and sulfur.