Hibiscus Care

The hibiscus is an elegant blooming plant whose popularity is growing in Texas, whether it is container cultivated around decks, porches, and patios, or used in landscape settings as annual color.

While individual flowers may last only a day or so, especially in the hot summer, from spring through fall many new buds are produced daily for a flower show second only to the rose in Brazos Valley gardens.

First classified by Linnaeus in Species Pantarum (1753) as Hibiscus rosa-sinensis, the hibiscus cited was probably the double red, which was widely distributed throughout China, India, South-East Asia, and the Pacific Islands. While the double red had been known known since the 1600s, it was only later, after Linnaeus made his first observations, that a single red form of the hibiscus was included in written descriptions. Singles were considered rare during these early days, until they were introduced into Europe from the South Indian Ocean.

By the 19th century, the hibiscus had made its way into the European greenhouses, as other forms were discovered and early hibiscus gardeners made cultivars. Most early forms were still originating from Asia and the South Pacific, but as early as 1820, Charles Telfair began crossing the Mauritius island native Hibiscus Liliiflorus with older forms of Hibiscus rosa-sinensis. By 1900, hybridizing had begun in Hawaii, India, Ceylon, Fiji, and Florida.

Gardeners can now choose from hundreds of hibiscus varieties, with more varieties introduced each year. The glossy green hibiscus foliage varies considerably in size and texture, and the range of flower colors seems to know no limits. We now have brown, green, gray, and maroon hibiscus, as well as violet, red, orange, yellow and pink, and white. Many hibiscus have multi-color combinations. Size ranges from 2 to 3 inch miniatures to the dinner plate size of the mallow, or Hibiscus Moscheutos, varieties. Three chapters of the American Hibiscus Society in are active in Texas, with Houston having the first and largest membership outside of Florida.

One of the drawbacks to using hibiscus in arrangements is that the flowers last only one day, especially during the summer. Nevertheless, hibiscus remains popular for decoration, since flowers need not be placed in water to prevent wilting.

For an evening party, try this tip: Pick hibiscus blooms in the morning, just as they are opening, and place them in a sealed plastic bag. Refrigerate them until one or two hours before displaying them. Then remove them from the bag and let them open on their own. Now they will last all evening!

Fertilizing Hibiscus

It has been said that a well-fertilized plant is the best therapy for combating insects and disease. Growers who provide routine care for their hibiscus experience few problems. You should feed hibiscus according to the label instructions of the fertilizer you select.

Hibiscus fertilizer is specially formulated to provide all the necessary plant food elements for successful hibiscus growing. The low phosphate content provides enough phosphorus for bloom, but does not have the excess amount of phosphorus that would tie up trace elements like magnesium. The potassium is derived from nitrate of potash, which lacks the the chlorides that are detrimental to hibiscus.

Be aware of what your fertilizer contains. Most general fertilizers use the less expensive muriate of potash, which is high in chlorides. Proper fertilizer is especially important to container grown hibiscus, as fluids move through the confined soil mix and are not dissipated.

Feed your plant when it is dry or just moist. Always water the plant first, then fertilize. Water again if a dry fertilizer is used. It is preferable to feed plants at cooler times of the day. Morning is ideal. Remember, the more you water in hot weather, the more you may have to fertilize.

Insects & Disease

With its lush tropical foliage, hibiscus in your yard can provide a tempting meal for hungry insects.

For cabbage loopers, cut worms and other worms, use Bio-Worm Killer or Sevin. Use bug and snail bait for snails and slugs. For insects like scale, mealy bugs, aphids, white fly and thrips, use general spray, DiSyston, or Ortho Orthene (Do NOT use malathion). BE SURE TO READ THE INSECTICIDE LABEL FIRST AND FOLLOW INSTRUCTIONS CAREFULLY.

For fungal problems ask an Heirloom Gardens Texas Certified Nursery Professional for recommendations.

Pruning Hibiscus

Protect plants when temperatures are expected to drop below 32 degrees or when there is a danger of frost.

Hibiscus planted in the ground: Before the first freeze, cut the hibiscus bush back to 4 to 6 inches above ground level. Cover hibiscus completely with pine needle mulch to give your plants a chance to survive a mild Brazos Valley winter. In the spring, after the danger of freezing has passed, rake mulch away from the trunk to allow plants to sprout freely.

Containerized hibiscus: Prune to shape in late January or February to assure ample spring blooms, as hibiscus bloom on new wood. Prune to shape or control the size of the plant at any time.

Plant Your Hibiscus Right!

Shown below is a hibiscus planted in a sunny location (at least 6 hours per day). The bed has been prepared and raised for good drainage. Blend approximately 14 bags of azalea planting mix per 100 sq ft of existing soil. Add the appropriate amount (according to instructions) of hibiscus fertilizer. A pre-emergent herbicide like Eptam, Balan or Surflan will prevent most weeds from germinating, and pine bark mulch will insulate the roots, retain moisture, and also help control weeds.

If planting hibiscus in a pot, we recommend that any container used be at least 14 inches in diameter, with holes in the bottom for drainage. Use cracked pottery to cover the hole, but still allow adequate water drainage then fill the blooming tropical soil mix blended with the appropriate amount of hibiscus fertilizer.

Fertilize every 3 to 4 weeks with hibiscus fertilizer. Especially designed for the Brazos Valleys soil and weather conditions, our 10-4-12 formula with added sulphur, iron, and trace elements will give you healthier hibiscus plants with bigger and better blooms.

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