The Hibiscus plant is an exotic plant that is known for growing large, bright, vivid flowers. These beautiful plants can add style and flash to any home or garden, though they do require special attention and care. Many times the soil it is planted in does not provide proper nutrients for the hibiscus to grow, so you must add fertilizer to supplement these loses.
On the packaging of any fertilizer you will see 3 numbers separated by a dash. These numbers represent the percentage portion of each major element found in the fertilizer in the following order: Nitrogen-Phosphorous-Potassium.
Nitrogen is used to aid in all metabolic processes and supports leaf growth. However, too much nitrogen can lead to leaf burns. It is important to use a fertilizer with a moderate amount of nitrogen. A nitrogen level of 10-20 is probably best.
Hibiscus plants do not tolerate phosphorus very well. Phosphorus gets into the soil and prevents key nutrients such as iron from reaching the hibiscus roots. This leads to weak flower blooms and wilted leaves. If you want full, vivid blooms it is suggested that you add a fertilizer that has a low phosphate count. Phosphorus levels as low as 5-7 is most ideal.
One of the most important nutrients hibiscus needs is potassium. Potassium aids in the process of photosynthesis, which creates sugar that is beneficial for flower growth. The problem is that potassium doesn’t stay inside the plants core, but rather floats around as a free ion. This means that a lot of these nutrients are lost anytime the plant loses water or begins to wilt. This is why it is important to add fertilizer that is high in potassium or has a last number above 10-15.
Hibiscus plants need constant fertilization. It is suggested that you fertilize your hibiscus about once a week during growing season, which is roughly March through October. In winter time the hibiscus won’t grow so it can go two months without any fertilizer.