UACES Facebook Hibiscus

Hibiscus

June 2010

QuestionWe have several hibiscus plants in our yard and every year the leaves get little holes, almost like filigree. The flowers are not affected but the leaves look terrible and don’t offer the lush green look we wanted in combination with the large flowers. Any suggestions?

 

AnswerThe insect in question is called a mallow sawfly. The females lay eggs in the upper surfaces of leaves, near the leaf margin, producing blister-like swellings. When the eggs hatch, the larvae move to the underside of the leaf and begin feeding. The larvae look like caterpillars, but they are actually more closely related to members of the bee family. They can be controlled with Sevin, Rotenone or Imidacloprid (Merit, Bayer Advance Tree and Shrub insecticide). If you don't control them they can turn the leaves into lace in a short period of time. While this really doesn't hurt the plants--they come back strong again next year, it is not the most attractive look. The species has up to six generations per year, and adults are active from mid spring until frost. Here is a link to pictures of what the insects look like.


June 2010

QuestionWe have five hibiscus plants in pots on our patio. My husband calls them my babies. Ha! One is a double bloom tree and the other four are regular ones. All different colors. We take them in the garage in winter and prune and put out in spring. This is the third summer we have had two of them and second for the other three. They are growing good and the leaves look great but are hardly blooming. The double bloom tree will have one or two blooms every now and then and one of the others the same. Three are not blooming at all, no buds, but they all look healthy. We have been told several different things to put on them but wanted to ask you. Do they need Phosphorus? We put Potassium { 0-0-60 } and start 'n' grow time release {18-6-12 } on them in the spring. Not being gardeners we need help. We live in Cabot and these plants are in full sun.

 

AnswerThis is a common complaint from folks who keep their hibiscus from year to year. Keep in mind that these plants bloom on the new growth. If the plants are large and possibly root bound, they won't grow a whole lot. They can be full of foliage and look healthy, but unless they are growing well, they aren't going to flower well. If you keep your plants from year to year, I suggest repotting every spring when you move them outdoors and cutting them back by at least one third if not by half. Then fertilize regularly--every week or two with a water soluble fertilizer and periodically with a slow release granular fertilizer. I would go with a complete fertilizer which has ample N-P-K (13-13-13 or 20-20-20) would be fine. Water as needed and they should bloom well. Or you can do what I do and buy new plants that are vigorous every year and get plenty of flowers!


July 2007

Question I have seen squirrels eating leaves from the lowest limbs of my two hibiscus. Besides getting mad as an old wet hen, - I have moved the pots away from the banisters of my deck, now the pots are on a table with chairs moved out of reach to the pests. They are eating the leaves yet. Will they eventually ruin my plants? They are not blooming as well as they have been although I am careful to keep them watered well. I have seen them get the buds and eat them. What can I do? I do have a large brown rabbit in the yard - but have never seen it on the deck.

 

AnswerOnce squirrels find a new food, they continue to feed on it unless you can deter them. They can ruin your hibiscus and keep it from blooming. Several things to try--scare devices, hot pepper sprays, etc. I have had a few gardeners tell me they used Vaseline and hot pepper sauce mixed and applied it to the rim of the pots. When the squirrels sat on the edge of the pots they got the stuff on their paws and licked it then stayed away. Apart from physically barricading your plants, there is no sure fire way to prevent damage--so try a combination approach and see what works for you. Rabbits usually won't eat anything higher than they can reach, so I think the culprit is the squirrels.


October 2006

QuestionI have a hibiscus and a calla lily that are being kept outside, but still in their pots. My question is what would be the best way for them to survive the winter? Should they be planted in the ground, left in the pots and outside or brought inside? Should I continue to water them (since they are still green)?

 

AnswerTropical hibiscus plants will not survive outdoors in Arkansas, whether they are planted in the ground or in a container. The Calla lily should survive outside, but would do better if planted in the ground, versus staying in a pot. Planted outdoors it will die to the ground after a killing frost. The hibiscus can either be brought indoors for the winter or treated as a houseplant--slightly less water than while outdoors, but do water and give it sunlight. Or it can be protected from freezing in a garage or storage building. In that case, water sparingly. It won't look perky when you move it back outdoors next spring, but cut it back, and it should bounce back and begin to bloom. If you are going to treat them as houseplants, they need to be inside now.


October 2006

QuestionI planted 3 hibiscus plants in my yard this past spring. They are about 3 1/2 feet tall now and really beautiful. How can I keep them from dying over the winter? Will it hurt to cut them back close to the ground...mulch well and cover with a bucket or something? They are not the hardy variety. I don't know what the winter weather will be like in SW Arkansas....it's always a surprise. Please advise me. I really don't want to dig them up if I don't have to.

 

AnswerIf you want them to be alive next spring, and they are the tropical forms of hibiscus, you better prepare them now for the move indoors or into a garage or storage building. (If you live in the northern part of the state, you may have already waited too long!) Tropical hibiscus will not over winter in the ground in Arkansas, even with extra protection. They can be treated as a houseplant, or even stored in the crawl space under your house. If you do plan to have them as houseplants all winter, don't be alarmed when they start a major leaf drop after the move indoors. Since they have experienced the cold weather we have had recently, the lack of humidity, stable temperature and lower light indoors, will give them quite a shock. You can always do what I do, and simply buy new ones every spring.


June 2006

QuestionI received a Hibiscus plant and would like some tips on growing and caring for it. It is a large bush which I will plant outside. I have always heard they are difficult to grow and maintain. Can you provide me with the proper ways of caring for it? It did not have any instructions with it at the time I received it.

 

Answer I assume you got a tropical plant rather than a hardy perennial type, since those are the more common gift plants. Tropical hibiscus plants can bloom all summer long. The main ingredients for success are full sun, ample moisture and monthly fertilization. You may want to give it a larger pot to grow in to make watering less tiresome, but they are easy plants to take care of. They are not winter hardy, so if you actually do plant it in the ground plan on digging it up and moving it indoors this fall or getting a new one next season.


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