A member of the mallow family of plants, the hibiscus is a tropical plant that does not tolerate cold temperatures. This evergreen plant produces oversized red, white, yellow, peach, pink or purple blooms that measure up to 15 cm (6 inches) in diameter. Hibiscus thrives when grown indoors under the right conditions and flowers prolifically when fed a well-balanced fertiliser. Like most tropicals, the hibiscus is quite content growing in a conservatory or greenhouse all year long.
Place the hibiscus plant in an area that receives indirect, bright sunlight. Hibiscus plants require at least six to eight hours of sunlight to thrive. If you cannot provide the adequate amounts of sunlight, set the hibiscus under a grow light.
Maintain an indoor temperature between 12 and 21 degrees C (55F to 70F). If you are unable to maintain the required temperatures, slip a plant heating pad under the pot. Set the plant heating pad to the required temperature.
Water the hibiscus plant weekly, allowing the top 2.5 cm (1 inch) of soil to dry out between waterings. Water the hibiscus deeply, allowing the water to flow through the layers of soil in the pot and out the bottom drainage holes.
Feed the indoor hibiscus plant a diet of 20-20-20 fertiliser. Apply the fertiliser according to label instructions. Hibiscus plants appreciate weekly feedings of water-soluble fertiliser solutions along with each watering.
Repot the indoor hibiscus into a pot that is the next size up, when it outgrows its present pot. Fill the pot with organic potting soil and set the hibiscus in the centre of the hole. Backfill and water deeply. You will know it is time to repot when the roots grow out through the bottom drainage holes or when the soil dries out faster than normal.
Cut back a third of the hibiscus plant using a pruning tool, in the early autumn. Remove the previous year's branches, as well as branches that are dead or damaged. Never remove more than a third of the plant with any single pruning.
Remove pests from the indoor hibiscus plant using an insecticidal soap. Apply the soap according to manufacturer's instructions.
Do not overwater the hibiscus. Standing water can cause the roots of the plant to rot. If the soil feels moist at a 2.5 cm (1 inch) depth do not add more water.