- 1). Locate a fertilizer that has a ratio of 17-5-24 displayed on the front of the bag. If you cannot find one with those exact numbers, look for one that has a ratio where the second number is the lowest, the last number is highest and the first number is in between the other two.
- 2). Read the ingredient list on the fertilizer bag to ensure that in addition to nitrogen, phosphorous and potassium, it also contains copper, magnesium and iron. These last three elements are important for hibiscus growth.
- 3). Water the soil under the hibiscus prior to fertilizing just until the soil is barely damp.
- 4). Apply the dosage of fertilizer recommend on the package instructions once per week by sprinkling it over the soil. If desired, you can also fertilize twice per week during the growing season by dividing the amount in half.
- 5). Water the soil after fertilizing the hibiscus to dissolve the fertilizer granules and make the nutrients available to the plant roots.
- 6). Repeat the fertilizer application until the fall months, when you should reduce fertilizing to every other week. Stop fertilizing in the winter and then start over again in the spring.
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