Hibiscus plants are tropical shrubs that have beautiful flowers that range from 2 inches to 1 foot in size. If cared for properly, hibiscus will be a long-lasting and lovely addition to your garden. Here’s how to grow hibiscus for the best results.
Hibiscus can be grown in the ground year round in areas where there is little or no frost in the winter. If there is any danger of frost in the winter, they should be grown in pots. In zones 9 and 10, they may be left outside in the pots and covered when there is danger of frost.
Cover with a thick layer of mulch or straw. Plastic should not be used as a cover unless there is nothing else available, as it is not much protection for the plants. Lay the plants on the ground before you cover them for extra frost protection. They should be brought inside for the winter in zones 8 and northward.
When bringing new hibiscus plants home from the nursery, make sure that they do not get too much sun at first. Grow them in partial shade until they are used to their new environment, especially if they have been transplanted into the ground.
The soil they should be planted in should be fertile and should drain well. Good drainage is essential for hibiscus, as the roots will rot easily if left in soggy soil. Use a mixture of topsoil, sand, and organic matter such as peat moss or compost. You can use perlite instead of sand if planting in pots, as the soil mixture will be lighter, making the pots easier to move around. The Ph of the soil should be 6.0 to 7.0. Mulch the plant if it is grown in the ground, but be careful to keep the mulch 2 inches from the trunk of the shrub.
Fertilize your hibiscus plants often. They require high fertility in the soil in to bloom well. Use a balanced fertilizer, such as 10-10-10. The fertilizer should also have some trace elements added. Alternately, you can use a low-phosphate fertilizer such as a 7-2-7 fertilizer.
This may improve the quality of the blooms. You may also spray the leaves of the plant with liquid fertilizer. Be sure to never use a fertilizer that is higher in nitrogen than in any other nutrient, or you will get a lot of leaf growth with few blooms. You should also cut back on the amount of nitrogen you fertilize your plants with as cold weather approaches, as this will help harden the plants for winter.
Prune your hibiscus to maintain its shape, remove dead wood, stimulate new growth, and to keep it a manageable size, especially if it is pot-grown. Make sure that all danger of frost is past before you prune the plants. Cold weather will damage the new growth that occurs after pruning.
Use very sharp shears. Cut the branch about one-quarter inch above an eye (the junction of a leaf with the stem). Make sure the eye points in the direction you want growth to go. New growth should sprout vigorously from the eye, and blooms should appear on the new growth in about three months.
Check often for insect infestations, as hibiscus plants may be bothered by whiteflies, scale, mealy bugs, thrips and aphids. If your plants are infested by aphids or thrips, use a soap spray made by mixing one tablespoon of soap to a gallon of water. You may also remove the aphids, and most other insects, by directing a strong spray of water at the undersides of the plant’s leaves. Whiteflies, mealy bugs and scale are controlled by using a fine spray of oil on the leaves.
Hibiscus plants require more care than many other garden plants, but the reward for all your work will be years of beautiful blossoms.