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This section collects contributions chapter members have made to help understand any aspect of the Hibiscus, generally through their discoveries and experiments. These were often reported in previous Petal Power newsletter articles. Do you have a contribution? Send an email to Gene and join the fun…now!
Rooting Experiments (August 2001, Dave Flanders) I am running experiments with rooting hybrids to see what would happen. All were planted individually in 4" pots (with exceptions noted), using Fafard 4P (45% peat, 20% vermiculite, 20% perlite, 15% pine bark) and rooting hormone. AHS data base statements relative to grafting vs. rooting are given where available. Orville Davis (AHS: graft): Started ten cuttings. After six weeks all but three cuttings were dead, and they died within the next two weeks. Conclusion: Propagate Orville Davis only through grafting. Eye of the Storm (AHS: graft): Started twelve cuttings. After eight weeks six cuttings are dead, and other six showed only original green but no new growth. After ten more days they, too, were dead. Conclusion: Propagate Eye of the Storm only through grafting. Sun Shower (AHS: Best Grafted): Started fifteen tip and wood cuttings in 4" pots. After 4 weeks new growth is obvious on only two cuttings, but others still have the original green. Sun Shower (AHS: Best Grafted): Started eight wood cuttings (no leaves) in one 1-gallon pot (4P + 1/3 Vermiculite). After 4 weeks 6 are growing leaves. On other two no new growth is obvious, but they still have the original green. Sun Shower (AHS: Best Grafted): Started eight tip cuttings in one 3-gallon pot (4P + 1/3 Vermiculite). After 4 weeks 1 is growing leaves. On other six no new growth is obvious, but they still have the original green. Conclusion: Propagate Sun Shower through grafting, Too early to tell, but rooting may have potential to work. Misfire (AHS: Graft): Started ten cuttings in individual 4" pots, in 4P+1/3 Vermiculite. After 4 weeks four are growing leaves. On other six no new growth is obvious, but they still have the original green. Conclusion: Propagate Misfire through grafting, Too early to tell, but rooting may have potential to work. Fifth Dimension (AHS: Best Grafted): Started seven cuttings. After 4 weeks 6 are growing leaves. On other one no new growth is obvious, but still has the original green (note: this is one of the varieties which Curt Sinclair reportedly sells commercially after successfully growing them on their own roots). Ruth Watson (AHS: Graft): Started two cuttings (compliments of a clumsy trespassing raccoon). Back to top Rooting Experiments Follow-Up (April 2002, Dave Flanders) The previously reported experiments with rooting normally-grafted hibiscus, indicating most had failed. About one I wrote: "Misfire (AHS: Graft): Started ten cuttings on 7/18/01 in individual 4" pots, in 4P + 1/3 Vermiculite. After 4 weeks four are growing leaves. On the other six no new growth is obvious, but they still have the original green. Conclusion: Propagate Misfire through grafting. Too early to tell, but rooting may have potential to work." Yesterday (4/4) I checked the five remaining pots of Misfire again. These remaining five were still alive, had green leaves and looked just slightly bigger than when I started them. I gently unpotted one, and found no roots! So I unpotted the others and found the same thing. These darn things had just sat there, drinking water and some nourishment from the soil, and teased me for almost nine months! Also looked at two of 8 or 10 remaining Senorita rootings and found the same thing. Bottom line: reserve your rooting efforts for those varieties known to root from cuttings, and to those you only want to fool around with without expectations of success." Back to top Mulching Potted Plants (May 2002, Gayler Boettcher) We have all heard or read about the many benefits of placing mulch around virtually everything in our gardens. Certainly the decrease in weeding alone is worth the cost (if any) and the effort required. Mulch has insulating characteristics giving somewhat lower soil temperatures – a real concern here on the Sun Coast. However, the emphasis on water conservation has given the subject of mulch an imperative tone that is continuously increasing in volume. I recently made some observations that dramatically illustrated the ability of mulch to reduce the amount of water usage needed to sustain plants. The circumstance involved four rose bushes planted in identical 16", self-watering pots. Two roses were planted last year and two this year. It soon became noticeable that the water reservoirs in the pots containing the new (and much smaller) bushes required more than 50% more water than the pots holding the old (and much larger) plants. Several weeks passed before the reason for the difference in water requirements came to mind. And indeed, mulch made the difference! The surface of the planting mix in the pots containing last years’ plants was covered with pine bark chips, but since the supply of chips had run out, the new plantings had no chips. After chips were placed in the pots with the 2002 plants, their water consumption dropped below that of the year-old plants – as one might have expected, everything being equal. Thus, we had a lesson about the significant difference mulch makes in reducing water evaporation. One would assume somewhat the same significant difference would exist for in-the-ground plants. Many members who joined our Chapter 8, 9 or more years ago had the pleasure of meeting a real hibiscus fanatic named Pete Boris. Pete raised hundreds of hibiscus and it seemed he gained his greatest pleasure from giving hibiscus plants to new Chapter members. It was difficult for a new member to leave Pete’s home without 6, 8 or 10 hibiscus plants. And each potted plant was sure to be surrounded by pine bark chips. Therefore, many Chapter members became indoctrinated in mulching potted plants – something pretty much unheard of "up north." To the pot-mulching practitioner, it is soon evident that the benefits extolled for mulching in-ground plants carry over to plants in pots (PIP). Fewer weeds, lower soil temperature and less water usage are all there. If you aren’t mulching your PIP, you are missing a good deal. Depending on the plant, its location, etc., the time and water saved may well be worth the small amount of effort mulching requires. And besides all the above, mulched pots look good – better than pots not mulched, in our opinion. Back to top Siamese Hibiscus Bloom (May 2002, reported by Dave Flanders)  Chapter members Marlyn and Bud Marshall discovered an exceptionally unusual bloom in their garden on May 12 (at least I've not heard of it before): a "Siamese" hibiscus bloom, pictured at the right.Two perfectly complete High Voltage blooms developed from the same calyx. There is a complete stamen and five petals in each bloom, as one would expect, and the colors are true. The calyx has more than five "petals," but all are arranged in one uniform structure, supporting the two blooms. Dave later reported, "Rae and I took the pictures down to Eric Golby. His reaction: ‘I'd say it’s impossible!’ He had never seen nor heard of such an occurrence in all his years!" Back to top Siamese Hibiscus Bloom: Commentary (May 2002, THML) Two significant comments were posted on The Hibiscus Mail List (THML@yahoogroups.com). Roz and Pat Merritt, Houston, TX, Lone Star Chapter, observed a Siamese hibiscus earlier and Pat reported: "I have seen that happen only once on our rosa-sinensis, but it is common with althea (rose of sharon - Hibiscus syriacus) blooms." Steve Sivek, Pasadena, TX, Space City Chapter, discovered a hibiscus example of this phenomenon from the bud stage onward, and had posted some fine pictures on his website. His THML comment was, "I had the same thing happen with Janys 5 years ago. The 2 blooms were almost exact mirror images of one another. You can see it at http://www.siveks.com/janys/Siamese.html Also had a Gerbera daisy bloom this way last week." Back to top Insects, Etc. that Inhabit Hibiscus: Review (March 2003, Gayler Boettcher, Frank Renault) The March 2003 issue of Petal Power contains a summary of The Bugs– R–Us slide program obtained from the AHS which is reproduced here. We credit Frank Renault for the original script which is very well done. Your average backyard garden is a virtual jungle of crawling, jumping, flying critters that may think of your garden as a salad bar! The good news is that there are also beneficial critters (insects) that can help us keep the damaging insects under control. Too often we destroy the beneficial insects as well as the pests with our insect control programs. Hopefully, after reading this information you will be able to identify the helpful ones, let them do their thing, thereby cutting your work and costs, and helping the natural environment. Remember, you may win a few battles with these pests, but never the war. They were here long before the dinosaurs and will be here long after you and I are gone. The LADY BUG BEETLE is one of the more common and easily recognized insects to be found in the garden. Its name dates back to the Middle Ages when it was called "The beetle of Our Lady", referring to the Virgin Mary. Now its name has been shortened to Lady Bug. It is also known as the Ladybird beetle. Some Lady Bugs have two spots, others as many as 32 spots. They come in different colors and most are about the same size. There are about 400 varieties found in the United States alone. They are very beneficial in keeping aphids under control. As a suggestion, don't go out and buy some from a commercial source. They will just fly away in a few days after eating all the aphids, and the aphids will soon reappear. A Lady Bug in the larval stage doesn’t look like anything you would want in your garden, but don't grab the bug spray! In the larval stage they have an even greater appetite for aphids than in the adult stage. Lady Bugs prefer aphids, but when food is in short supply they will eat mites, thrips and other small Insects. There are four stages of development of an insect: egg, larval, pupal and adult. Since each stage varies dramatically in appearance, recognizing an insect can be difficult. APHIDS are the most common insects to be found in a garden. They tend to gather on tender new growth, are soft bodied, and don't fly. They come in many colors, but green is the most common. Over 1350 species of aphids are found in the United States. They reproduce rapidly without egg fertilization. In limited numbers they are not a major problem, but they can carry plant viruses which kill plants. ANTS love eating the honeydew that aphids excrete and will protect them, and herd them like cattle from one plant to another. There are two easy non-insecticidal ways to deal with the ant-aphid connection. The first is to apply a sticky ant barrier strip around the base of the plant trunk. This forms a mechanical barrier that keeps the ant off of the plant. A second way is to spray the plant with diatomaceous earth (DE). This non- toxic powder is very sharp and cuts the soft under-bellies of ants (and other soft-bodied insects) if they crawl over it, and they will die within a few hours. Use the agricultural grade DE, and not the type for swimming pools. Also follow the manufacturers safe use recommendations, such as wearing a mask to avoid inhaling the DE powder. Also, Safer Soap and Orthene can be used to kill aphids. (Editor’s note: Orthene as such is no longer available, however it is in an Ortho product Isotox, along with a miticide "Vendex".) Remember when spraying plants with insecticides, to be sure to spray the underside of the leaves as this is where most insects prefer to live. A fungus known as Sooty Mold will begin growing in the secretion of the aphids and other insects. It is black in color, unsightly, and looks as if you have cleaned out the fireplace and thrown the ashes on your plant. An oil emulsion sprayed on the leaves at night will loosen the fungus. The next morning before the sun has dried the leaves, direct a strong blast of water to the leaves. That will wash off most of the mold. Additionally, the water will wash off the aphids. If you rid your plants of the aphids, the sooty mold problem will disappear by itself. THRIPS are 1/16 to 1/4 inch long and slender. These bad bugs live in the flowers and tender new leaves. The adult lays its eggs in the flower buds where they will hatch in a few days. They then suck fluids until they drop to the ground where they pupate in the soil. Eventually they emerge as flying adults. Their life cycle is two to three weeks. SIX-SPOTTED THRIP is one of the many varieties of thrips. A few are actually beneficial and eat other thrips, aphids and spider mites. The six-spotted thrip eats spider mites. As a general rule, however, most are not beneficial. You may control those thrips with Safer Soap, Neem oil. Predatory mites and lacewing larvae can be purchased from a commercial source, and unlike Lady Bugs, are not as likely to leave the area of your plants. For chemical control, if required, use Avid, Orthene, Mavrik or Dursban. Garlic cloves and peppers, can be boiled together to make a tea, which can then be sprayed on the plants for a more environmentally friendly insect control. The bad news about the PINK HIBISCUS MEALY BUG is that it is now in Florida. It is in many of the Caribbean Islands and was also recently discovered in California. It attacks hibiscus and more than 200 varieties of other plants. Pesticides do not penetrate its waxy coating and are virtually useless. It also reproduces extremely rapidly. A tiny wasp (Anagyrus kamali), which has been imported from China, is a parasite of the Mealy Bug and kills it by laying its eggs inside the adult Mealy Bug. It has proven to keep it under control where it has been released, and has reduced the Mealy Bug population by up to 90 percent. The Department of Agriculture is prepared to use this wasp in the United States. Another natural predator that is already in the U.S. is the Mealy Bug Destroyer. One Mealy Bug Destroyer can kill 3 to 5 thousand Pink Hibiscus Mealy Bugs in its life cycle. Again, the larva stage of the LARVA MEALY BUG DESTROYER does not look like the adult stage. In fact it looks very similar to a Mealy Bug. They move very fast and are larger than a Mealy Bug and have legs, which helps distinguish them from Mealy Bugs. So look closely before you start killing this insect to make sure it's a Mealy Bug and not a Mealy Bug Destroyer. The IO MOTH is a common moth in South Florida, and is of little worry to gardeners, until it turns into the IO CATERPILLAR. There are two major problems with this caterpillar. First, it has a tremendous appetite. A few of them can strip a hibiscus plant of all its leaves in a day. Second if you come in contact with one you will feel intense pain for several minutes. Simplest control is to grab a set of gloves and a pair of clippers and cut them in half. Another effective control for most caterpillars is Bacillus Thuringiensis (B.T. for short). This is a spray that contains bacteria that will kill most caterpillars in a few hours and is available at most garden centers. The common GARDEN SPIDER is not dangerous and should be encouraged, at least in the garden. Like most spiders they are beneficial destroying many pests in the yard. Many insects are so small it is difficult to see them with the naked eye. A ten power hand lens will make your detective work in the garden much easier. In order to see SPIDER MITES you will need a hand lens. If you don't have a hand lens you can detect their presence by the webs they weave between leaves and branches, hence the term "spider" mites. You can readily tell the presence of spider mites by the damage they do. First, several small areas of the leaf will turn yellow. These areas grow in size until the leaf is entirely yellow and falls off. Spider mites are a frequent and severe problem, especially in warm, dry weather. Treatment includes spraying the underside of leaves with a jet spray of water, and washing them with Safer Soap or Palmolive Gold soap. Certain chemicals such as Sevin should not be used because it causes the mites to reproduce faster. Spider mites produce dark scarred tissue on the underside of leaves by sucking fluid from the leaf. Note that spider mites are located on the underside of the leaf. Luckily there are natural predators of this pest. The spider mite destroyer is actually a type of Lady Bug. As its name implies, its main meal is spider mites. Other natural predators include predatory mites, six spotted thrips, as mentioned earlier, certain flies and lacewing larvae. ADULT LACEWINGS need nectar, pollen or honeydew to feed on or they will fly away, and you don't want them to do that. So always keep flowering plants around for them to feed on. The LARVAL LACEWING is also called the "aphid lion" because it has a lion of an appetite. It will eat as many as 200 aphids per day. They also eat mites, thrips, Mealy Bugs, and immature white flies. Now, is this a great fellow or what? Unfortunately, if no other food is around, they will eat each other. In the larval stage they can travel 80 to 100 feet per day. Don't confuse them with thrips, which look similar. Also, commercial food is available to keep them in your garden. Now let’s talk about MEALY BUG. The good news about these bad bugs is that they are easy to spot. Their bodies are very soft and they look like small flakes of cotton. Unfortunately they do multiply rapidly and quickly spread on the infected plant and to other plants. Small outbreaks can be treated with isopropyl spray or Murphy's Oil spray. Again, always be sure to spray the underside of the leaves. And a great natural predator is the Mealy Bug Destroyer, discussed earlier. Not to be confused with the larger Lacewing is the greenhouse WHITEFLY. As its name indicates it is white in color. Shake a branch and you can easily see these pests flying for a few seconds and landing back on the plant. Another way to detect whiteflies is with the use of sticky yellow traps. They are attracted to yellow and are easy to recognize on the trap. Yellow traps are usually made of plastic and are covered with a sticky material. Since many insects, especially thrips, are attracted to yellow, this is the color most often used. The sticky stuff is called "tangle foot" and is available from mail order garden suppliers. Some have tried the trap in their garden and gave up on it because too many beneficial insects and newly hatched insect-eating lizards were getting trapped. Natural enemies of white flies include larval lacewings, ladybug beetles, and Encarsia Formosa (more about E. Formosa later). Chemical controls include Neem (a natural insect repellent from the Neem tree), insecticidal soap, Orthene, Avid and Merit. A tiny parasitic wasp, Encarsia Formosa, lays its eggs in the larva of the white fly. This is another beneficial that is available through a garden supplier. The name of the HAND GRENADE SCALE refers to its resemblance to a miniature hand grenade. It grows on the main stems and trunk of the hibiscus bush. Several years ago it was a major problem but today it occurs less frequently. Control them in cooler weather with 3 applications of Cygon at two-week intervals, and expect to lose a few leaves from your plant. On a small outbreak, use a brush and paint the affected area to minimize the dropping of leaves. WHITE SNOW SCALE is easy to spot growing next to darker colored bark. It prefers damp warm weather. Mulch against a bush trunk also encourages its growth. It usually is spotted on the trunk near the soil line, and in time works its way up the stem, eventually covering the entire plant. Small outbreaks on stems and trunks can be treated with PAM cooking spray or WD 40. (Note: Apply Pam or WD40 to wood only –not leaves.) For larger outbreaks, spray them with Cygon. Remember to use Cygon in the cooler months of the year to minimize leaf damage. Wrapping a plant label around the main trunk of a plant is similar to the effect that mulching close to the trunk has and will greatly increase the chance of getting snow scale. Placing a label stake away from the plant trunk will reduce the chance of developing snow and other scales. Incidentally, if you mark the labels with a Number-2 lead pencil, the markings last much longer than those made with indelible pens and laundry markers, and they don’t fade even after several years. Unless you get up early in the morning or it's a rainy day, you may not see snails, but you can easily see the damage they do. If you see leaves with large holes, especially in the center of the leaf, snails probably did it. Unconventional ways of controlling them include sprinkling salt on them or filling a flat dish with beer. The only problem with the beer method is that often they do not drown, and they may keep you and the neighbors awake all night with their singing. A favorite and effective method, if there are just a few, is the hammer and brick method. If you see a possum or raccoon in your garden, they may be looking for snails as it is one of their favorite foods. Commercial baits such as Bug-Geta or sprays like Slug-Fest also work well. A spray mixture of 3 to 4 ounces of Clorox in one gallon of water applied to the soil late in the day reportedly is also effective. The GALL MIDGE, first recognized in 1997, is now prevalent throughout Florida. A small fly lays its eggs in a developing flower bud, causing the bud to drop off before flowering. When the bud falls to the ground, the larva burrows into the ground. The small larvae are 1/8th of an inch long, and light yellow to white in color. If you have buds that are dropping and suspect it may be due to midges, there is an easy way to confirm your suspicions. Take some buds that look like they are about to fall off, cut them in half and put in a clear, sealed plastic baggie. If midges are present they will come out of the buds in a few minutes and will be easy to see by holding the plastic baggie next to a dark background. If you want to be absolutely sure they are midges, put a couple in your hand. If they jump several inches, they are midges. Effective control is difficult and still under research. If all else fails, learn to share. The war with insects is one you cannot win. Be happy to keep them under reasonable control. Give Mother Nature a helping hand when needed, and use chemicals sparingly. Why spray an entire yard when only one plant may be infected? Back to top | ||||
