A Hibiscus plant is an outdoor plant in tropical and sub-tropical areas throughout the world. However, a hibiscus plant also does well as an indoor plant in warm, temperate climates. There are hundreds of varieties of hibiscus and all bloom indoors if cared for correctly. However, the flowers may be smaller than when the plant is grown outdoors. Many new hibiscus varieties are hybrids; this means they are grown from tissue cultures in greenhouses.
Hibiscus plants, upright, woody bushes with dark glossy maple-leaf shaped foliage, produce large, beautiful flowers in orange, red, yellow, pink, and white. The size of the blooms may be as small as 2” or as large as 10”-12.” A Hibiscus plant can be 1′-15′ in height depending on whether it’s growing in a pot or planted outside. Hibiscus plants also make beautiful topiaries and bonsai plants.
Buds fall off a Hibiscus if the plant is stressed by a change in location, temperature, too much fertilizer, or water. The double bloom variety of Hibiscus plants is especially prone to bud drop.
The majority of the flowers on Hibiscus plants last just one day. There are a few Hibiscus varieties that have blooms that live 2 or 3 days. In cooler weather, Hibiscus flowers may last a little longer.
I would try something less harsh to get rid of Aphids such as the green solution (recipe in the Glossary), yellow sticky cards, or insecticidal soap. You may get rid of the Aphids by putting Hibiscus plants outside in cold temperatures, but you’ll also kill all the new growth and probably some of the mature leaves as well.
Using the right fertilizer is very important if you want Hibiscus plants to produce flowers. You may be using a plant food that has too much nitrogen and not enough potassium. The first number on the fertilizer label represents nitrogen, the second number phosphorous, and the third number potassium. 10-10-10 is a basic balanced plant food. Look for a fertilizer that is 10-5-15, one that is high in potassium. Also, giving a Hibiscus plant more sun, pruning them frequently, and keeping them root bound in smaller pots helps to produce more flowers.