____GARDEN TALK ____
EDITOR’S NOTE: University of Florida/IFAS Extension Director for Nassau County and Horticulture Agent III, Rebecca Jordi addresses questions about landscaping and gardening in northeast Florida. She is also a University of Florida faculty member. _________
QUESTION: I have noticed a few commercial and governmental sites in Central Florida have been using Jerusalem Thorn as a parking lot tree. Why don’t we use it more often here? It seems like a care-free tree. PO
JORDI: Usually the biggest deterrent to using new or different trees in commercial and government sites is because these areas are often regulated by local ordinances which can be difficult to change or alter. In addition, availability of tree varieties is often very limited by the nursery growers stock. Growers want to produce what will sell (which is why they are in the nursery business) and unusual trees can be very risky. The only other downfall of this particular tree may be its short life span which is only 15-20 years. However, most of us know trees in urban areas are not long-lived anyway because urban environments are often extremely severe.
The Jerusalem Thorn tree will tolerate very hot and dry conditions which would make it a great median or parking lot tree. This tree has strong wood and with its natural open shape allows it to tolerate high winds well. For the reasons stated above, it would be a good addition to some commercial sites but it should not be planted in an area which would be receiving irrigation twice a week, which often occurs in lawn grass landscapes. (Photo from Berkley.) See also publication from the University of Florida on the Jerusalem Thorn.
QUESTION: I decided to clean out the shrub beds and remove the old wood mulch. When I did, I dug up dozens of roly-poly bugs, the insects which roll up into little balls when you touch them. Should I be concerned about finding so many of these insects in my shrub bed? JD
JORDI: I applaud you for removing the old mulch instead of just piling more on top – it is a great spring project and should be done every few years or so. Mulch should only be about 2-3 inches thick and never piled up against the trunk of any tree or shrub.
You most likely have uncovered dozens of pillbugs, which are actually crustaceans, not insects. Remember, insects have three body parts and only six legs whereas pillbugs have numerous armored body segments and well over six legs. Pillbugs are wingless and active during the night time hours preferring to stay cool in the damp mulch during the heat of the day. Their reaction to touch by rolling into a ball may be why they were called “pill” bugs or roly-polies. For the most part, pillbugs feed on decaying organic material but occasionally they do feed on the roots of our prized plants. Pillbugs can be found throughout Florida, anywhere decaying mulch, leaves or grass clippings are deposited. The female carries 7 to 200 eggs in a pouch on her underside for 3-6 weeks until the eggs hatch. She will carry the young around for another 6 to 7 weeks, which is a fairly long period of time for many insects.
Pillbugs can cause damage to young vegetable plants and fruit with their rasping mouth parts but they are generally considered of no economic importance as they prefer to feed on decaying material when it is available. See also publication on common crustaceans from the University of Florida.
QUESTION: What can you tell me about the Flamingo plant? KT
JORDI: The Flamingo plant, Jacobinia carnea, is a perennial which is suitable for cold hardiness zones 8b – 11. Remember Northeast Florida is in zones 8b – 9a. The plant can reach heights up to 7 feet with a three foot spread so before adding this plant to your landscape be sure you have sufficient room. The flowers come in rose-purple, red, yellow, orange, apricot, or white which periodically bloom from late spring though early fall. With so many choices of flower color, it would be surprising not to have some place in the garden available for this lovely plant. Jacobinia should be grown in dappled light or partial shade. It prefers moist, well-drained soils but it is not picky about the soil pH. Jacobinia is not salt tolerant therefore it would be a poor choice for coastal areas, along the beach or sand dunes. Dead-heading helps improve flowering as well as stimulate new growth. For this reason, light pruning should be performed throughout the growing season. Propagation can be done by cuttings. When planting, provide several feet between each plant to allow for spreading. Jacobinia has no known serious disease issues and so far has not caused any concerns over invasive characteristics. (Photo from Texas A&M University.) See also publication from the University of Florida on the Jacobinia carnea.
GARDENING CLINICS & PLANT SALE
May 16, 2011 – Plant Clinic at Nassau County Extension office. Becky Jordi, Nassau County Horticulture Extension Agent will conduct a Plant Clinic from 10 am until 2 pm at the Yulee Extension Office (A1A and Pages Dairy Road). All County residents are invited to bring plant samples showing problems in their landscapes. Problems will be identified and solutions offered for correction (there is no fee for this service). Nassau County Master Gardeners are also offering plants for sale at the May 16th Plant Clinic. For more information call 491-7340.
Rebecca L. Jordi
Director, Nassau County Extension
UF/IFAS Environmental Horticulture
543350 U.S. Highway #1
Callahan, FL 32011
904 491-7340 or 904 879-1019