Hibiscus: The numerous varieties of “the rose of China” have large beautiful flowers

The luscious pink petals surround the pink style. On top of the style is the dark pink stigma which will capture the dark yellow pollen from the anthers below. A colorful tropical beauty, this is the hibiscus variety called Seminole Pink (shown at right).
Hibiscus is a flower often associated with the tropics. Its large blooms of up to nine inches in diameter have a stunning, glamorous simplicity.

And oh the colors! The six basic ones — white, red, orange, yellow, lavender and brown — are only the beginning. After that, there are hundreds of possible colors to choose from amongst the numerous varieties of hibiscus available.

The hibiscus are a favorite because they bloom all year round. Hibiscus plants range from trees to shrubs to herbaceous annuals in a family that has even more varieties than roses. In fact, the genus Hibiscus is the largest in the Malvaceae or Mallow family’s 1500 species.

Hibiscus The numerous varieties of “the rose of China” have large beautiful flowers 300x253 Hibiscus: The numerous varieties of “the rose of China” have large beautiful flowers

Hibiscus: The numerous varieties of “the rose of China” have large beautiful flowers

Though hibiscus originated in Asia and the Pacific Islands, they are now found in a much wider range that encompasses northern Europe, West Africa, the eastern Mediterranean, India, North America and South America. Hibiscus relatives in the U.S. include the beloved hollyhocks and hardy hibiscus of the temperate climes and cotton and okra in the South.

1,000 Varieties
The species Hibiscus rosa-sinensis, whose common name is the shrubby rose-of-China, is the one tropical gardeners love. It produces stunningly beautiful flowers of gorgeous coloration on bushes of dark green, unlobed leaves. Its beauty has made it the state flower of Hawaii.
The five-petaled hibiscus flowers have distinct protruding stamen tubes and pistil tips. The petals come in six basic colors that are deeply saturated: white, red, yellow, orange, lavender and brown. But many color variations are available among the 1,000 hibiscus varieties. Hibiscus flowers are characterized as either single or double form with variations in petal number and arrangement. Single hibiscus always have five petals, while the double form has more than five petals. If a hibiscus has petaloids (smaller petals), then it is a “crested” single or double.

Though hibiscus flowers seem to appear suddenly,preparation for blooming is evident up to a week before. The slightly gaping sepals of the expanding bud (left) offer observers a peek at the brilliantly colored petals. Unfortunately, the flowers do not last long; indeed, within hours of blooming, their colors may change and by nightfall, many drop off, turning dark and softening.

Making New Varieties Via a Hybrid
Making new varieties by creating a hybrid is not difficult and is exciting because you never know what kind of flower you will get.

Once you create a hybrid, it will be six months to two years before the plants bloom because the new hybrid seedlings have a difficult time developing good root systems.

The hibiscus are a favorite because they bloom all year round. Hibiscus plants range from trees to shrubs to herbaceous annuals in a family that has even more varieties than roses. In fact, the genus Hibiscus is the largest in the Malvaceae or Mallow family’s 1500 species.

Though hibiscus originated in Asia and the Pacific Islands, they are now found in a much wider range that encompasses northern Europe, West Africa, the eastern Mediterranean, India, North America and South America. Hibiscus relatives in the U.S. include the beloved hollyhocks and hardy hibiscus of the temperate climes and cotton and okra in the South.

To give your hybrid a better root system, graft it onto a plant that has one. To prepare a superior root system, grow understock from a plant with good roots, such as Allea, a hibiscus with small pink flowers.

Growing Understock
1. Find some vigorous straight wood.

2. Cut the wood into 12-inch pieces.

3. Dip the pieces into Captan fungicide and allow them to dry.

4. Dip the bottom ends into Root-tone.

5. Insert well into 4 inches of Perlite/oak tree leaves in a large container.

6. Five to eight weeks later, these stalks should be well-rooted and quite tight in the pot.

7. Pot them separately with 1″ of soil from big pot in 4-inch containers containing sandy soil and Lorne Peat (not Canadian peat as it is too acidic). The seedlings should be 6-8 inches in height when ready to be used as understock

After you grow understock, perform a graft to create a hybrid.

Performing a Graft
To perform a graft, you need a knife, wax, rubberbands and tags.

1. Do a veneer side graft by using a knife to make a long cut that exposes the cambium or growing layer on the host (or well-rooted) plant.

2. Make a second cut, leaving a notch or tab at the bottom.

3. Cut a scion (a 2-inch piece) of the new hybrid seedling to match the cut on the host plant.

4. Place the scion into the cut on the host plant and wrap with rubberbands.

5. To protect against infection, seal the graft with wax to prevent moisture from entering the graft and perhaps causing a bacterial or fungal infection.

6. Put on a tag that identifies the variety.

7. Four weeks later, cut the top of the root stock off, thereby leaving the new hybrid to grow on a new healthy root system.

Hibiscus as Cut Flowers
Hibiscus make lovely additions to the flower arrangements for a dinner table or for an evening party. The best time to pick them is in the morning. Though they do not have to be put into water after they are picked, keep them in a reasonably cool or refrigerated place until you need them.

Growing Tips
Hibiscus are quite easy to grow. Choose varieties both for their flowers and their growth habits so that you will be successful in growing hibiscus.

Since grown hibiscus bushes range in height from an average of 4 feet to a maximum of 12 feet, plant bushes from your local nursery 3 to 5 feet apart. If you plant them too close to one another, they will be too crowded when mature. Protect your hibiscus from cold northern winds.for blooming is evident up to a week before. The slightly gaping sepals of the expanding bud (left) offer observers a peek at the brilliantly colored petals. Place plants in holes that are 6 inches wider than their root balls. One third of the dirt in the hole’s bottom should be organic matter (peat moss, dehydrated cow manure, or compost). Place the hibiscus plants at the same depth in the soil that they were in the nursery containers. To prevent them from being blown over, tie them to stakes. Also, hibiscus are not salt-tolerant.

Propagation
Hibiscus can be propagated from cuttings, or by employing air layering or grafting. Take cuttings from soft wood or new growth in the spring and summer and place them in a well-drained medium. An example medium would contain equal parts of fibrous peat and coarse sand. These cuttings usually root in about six weeks. The plants begin to flower in about nine months.

For hibiscus varieties that do not root readily from cuttings, air layering or grafting is another choice.

Air Layering to Propagate Hibiscus
1. Remove a wide band of bark (one-half to one inch) from branches one-half inch or larger.

2. Surround the wound with moist sphagnum moss, seal it with a plastic wrapper, and secure it with rubberbands, tape, or string.

3. Wrap the plastic with newspaper or aluminum foil to provide shade for the new roots and prevent birds from pecking at the plastic.

Performing a Graft
To perform a graft, you need a knife, wax, rubberbands and tags.

1. Do a veneer side graft by using a knife to make a long cut that exposes the cambium or growing layer on the host (or well-rooted) plant.

2. Make a second cut, leaving a notch or tab at the bottom.

3. Cut a scion (a 2-inch piece) of the new hybrid seedling to match the cut on the host plant.

4. Place the scion into the cut on the host plant and wrap with rubberbands.

5. To protect against infection, seal the graft with wax to prevent moisture from entering the graft and perhaps causing a bacterial or fungal infection.

6. Put on a tag that identifies the variety.

7. Four weeks later, cut the top of the root stock off, thereby leaving the new hybrid to grow on a new healthy root system.

Light
Hibiscus are sun lovers; they grow best in direct full sunlight. Those with lavender, brown and green flowers do best in partial shade and others dislike full sun on the hottest summer days.

Water
Oddly, hibiscus need lots of water, but can’t tolerate “wet feet.” After planting your hibiscus in the ground, be sure to water them often — every two days. Potted plants require water once a day. If a potted plant requires more than daily watering, the plant needs a bigger pot.

The water should be in a sufficient amount that the soil is wet to a depth of 12-18 inches. But it is very important that the soil drains well.

Soil
Hibiscus plants grow best in sandy soil with a pH of 5.5-6.5. Check with a local nursery to find out if your city’s water changes the pH of your soil.

The soil where you plant your hibiscus needs to drain well; if it does not, set them in a raised bed that is 12″-18″ off the ground.

Hibiscus are not acid-loving plants. If you have acidic soil, add lime to the soil.

To reduce water evaporation, prevent erosion, decrease weed problems and control nematodes, mulch with small leaves and wood chips.

Fertilizer
Fertilization ensures strong, healthy hibiscus plants that are more resistant to pests and disease. Since hibiscus are heavy feeders, it is best fertilize them often and lightly.
Before and after fertilizing, water the plant to prevent fertilizer burn. Spray water-soluble fertilizers on leaves (foliar feeding) of in-ground and potted plants, spread it beneath the canopy and on the branches but not on the stem.

Use fertilizers with minor elements such as iron, copper, boron, etc. as they are essential for the proper balance of growth. That is because they induce the absorption of all other elements.

Once a month, fertilize in-ground plants with 10-10-10, a dry fertilizer. Some growers prefer 7-2-7 as they believe the low phosphate helps produce the best quantity and quality of flowers.

During the high-growth season — summer, use a fertilizer with a higher nitrogen content such as 10-5-5.

Potted plants seem to like Peters Peat Lite Special with a 20-10-20 formula. Also, add an ounce of magnesium and a tablespoon of iron to potted plants each month.

Every two months, fertilize with manganese sulfate to promote growth of branches and flowers.

In alkaline soils, fertilize with iron chelates (Sequestrene 138) to correct iron deficiencies.

With extreme soil conditions, such as the limestone soils of the Miami-Homestead area, use foliar sprays of micronutrients 3-4 times a year.

While some gardeners fertilize hibiscus once a month, others do it just four times a year: in the early spring, after first growth flush, midsummer and early winter. Experiment to see what works best for you.

Pruning
Hibiscus flowers are produced on new growth achieved by pruning. Pruning also shapes future growth, enlivens old plants, manages plant size and eliminates diseased and dead wood.

Prune hibiscus heavily in the early spring, not in the late fall or winter. Light maintenance pruning may be done throughout the year.

Pruning Hibiscus
To prune a hibiscus, always utilize sharp, clean pruning shears.

1. Place your shears just above and angled down and away from an “eye” or node, the junction between a leaf and the stem.

2. Then, make a clean cut. (Cutting the bush at this junction activates a small bud in this location.)

3. To shape future growth, prune just the longest third of the branches.

4. Four to six weeks later, prune the next longest third.

Pests
Check your hibiscus for chewing pests, including caterpillars, grasshoppers, snails and slugs, beetles, cutworms and leaf miners.

Hibiscus can also be damaged by creatures that suck plant juices. Among them are scale, mealybugs, spider mites, aphids, whiteflies and thrips. Often, these parasites invade because the hibiscus suffers from poor air circulation.

If large populations of these pests develop, it is harder to rid the plants of them. Solve most insect problems by applying a solution of 1 teaspoon of Orthene 75% WP or 1/2 teaspoon of Mavrick dissolved in a gallon of water.

Scale can be killed by spraying the infected plants with PAM, the spray-on cooking oil. Cygon also fights scale. NEVER use Malathion on hibiscus.

Nematodes are small round pinworms that attack hibiscus roots. Symptoms include frequent wilting; poor growth shown by small, stunted leaves; and nutritional deficiencies. To control, sterilize plants before planting them and mulch. If needed, add 1/4 teaspoon of Oximyl 10% to a gallon of soil every 4 months.

Bud drop may be due to the presence of thrips, caterpillars, or nematodes. Constantly check your plants for these pests, thereby preventing overuse of pesticides. If you discover any, consistently apply contact or systemic pesticides. Before using insecticide, water the plant thoroughly to reduce shock. Read the label on the insecticide carefully. Spray both the leaves’ tops and undersides either early in the early morning or evening when it is less than 80° F.

Diseases
Hibiscus can fall prey to diseases caused by bacteria and fungi, such as leaf spots. Though some leaves may die, the spotting is usually minor. Remove dead leaves.

One tablespoon of Agricultural Streptomycin in a gallon of water fights bacteria, while putting a tablespoon of Kocide DF in a gallon of water controls fungus. Five tablespoons of Daconil in a gallon of water controls fungus and bacteria.One fungus, mushroom root rot, is quite deadly. Infected plants usually wilt before dying. Poor draining soil or buried tree stumps and roots contribute to the disease spreading. A sign of infestation is a white film under the bark near the base or clusters of tan-to-brown mushrooms. Remove dead plants and either sterilize the soil with Vapam and then replace it or add new soil.

For Non-Tropical Areas
Grow hibiscus in pots. In the winter, bring them inside to a spot where they receive 3-4 hours of sunlight per day, supplemented with artificial light.

In the winter, regularly fertilize hibiscus. Before a frost, cover in-ground plants with plastic all the way to the ground but keep the plastic above the foliage to prevent the plant from being burned.

While non-grafted or “garden” varieties will emerge from a plant’s roots whose upper parts were killed by 28-30° temperatures, it is better not to risk viability.

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