This tomato hornworm is being parasitized by beneficial wasps. Photo credit: Henry Crenshaw
Why would anyone allow dozens of wasps to thrive in their garden? Why would they let caterpillars keep moving through their pepper bushes? Don’t they know you can spray for that?
As Extension agents, one of the tenets we “preach” in gardening is the concept of Integrated Pest Management (IPM). This technique involves a series of insect control measures that begin with the “least toxic” method of control, using chemicals as a last resort. One of those least toxic measures is “biological control”, in which a natural predator or parasite is recognized and allowed to remove a pest insect naturally. It is important to be able to recognize some of the more common garden predators and parasites. Many times these insects look strange or dangerous, and they are mistaken for pests and killed.
One such beneficial insect to the home gardener is the braconid wasp (Cotesia congregatus). Most people shudder at the mention of wasps, but these tiny (1/8 inch long), mostly transparent wasps are of no danger to humans. Quite the opposite–they are an excellent addition to gardens, especially if you are growing tomatoes or peppers. One of the major pests to these favorite vegetables is the tomato hornworm (Manduca quinquemaculata), a fat green and white-striped caterpillar.
The beneficial wasp can control hornworms because females lay eggs under the caterpillar’s skin, after which the eggs hatch and larvae feed on the hornworm. After eating through the caterpillar, they form dozens of tiny white cocoons on the caterpillar’s skin. The tomato hornworm is rendered weak and near death, and the vegetable crop is saved.
If you happen to find a tomato hornworm covered in these small oval cocoons, consider yourself lucky. Let the process continue, allowing the new generation of beneficial wasps to hatch and continue their life cycle. They will control any future hornworms in your garden, and the whole process is fascinating to watch!
For questions on integrated pest management, beneficial insects, or growing peppers and tomatoes, call your local County Extension office.
A few months ago I visited a property that had been renovated to clean up some limbs that were in danger of falling on the house. Pruning tree limbs that are in danger of hitting a structure is always a good idea, but it’s important to look at the impacts this practice may have on the rest of a landscape. Any time the light profile of a landscape is changed, current and future plant selection must be considered. One often seen example occurs when trees grow to full size and shade out the lush lawn that’s underneath. However, in this case, removal of limbs allowed more light to shine on some beautiful, old camellia bushes.
Camellia Planting and Care
Camellias do best in locations that receive filtered sunlight and are protected from the wind. They like acidic, well-drained soils. Trees and shrubs are generally planted 2″ to 3″ above the soil grade. (2″ to 3″ of root ball should be exposed above the soil grade when the tree/shrub is planted.) To help improve root oxygen exposure and help prevent a root rot situations, camellias can be planted slightly shallower than the previously stated recommendation. For more plant establishment guidelines, please visit: UF/IFAS Planting and Establishing Trees Guide
Scenario and Diagnosis
As mentioned above, the property in question was visited to diagnose sick camellia bushes. Upon further inspection of the property, asking about recent changes to the landscape, and inspecting the bushes, it was clear that the camellias were receiving too much sunlight. Sunlight damage was expressed by large brown sunscald spots on the yellowing leaves.
Sunscald damage on camellia leaves. Photo Credit: Jed Dillard
The camellias had also been pruned incorrectly. Camellias require minimal pruning. They are normally pruned to control size or promote a tree form structure if desired. Any pruning should be done before flower buds form in late summer.
An incorrectly pruned camellia bush. Photo Credit: Jed Dillard
Solution
The best solution in this scenario was to dig up the affected camellias and move them to a location with more shade. Sun loving shrubs were suggested as options to replace the camellia bushes. It’s important to note that Camellia sasanqua cultivars are usually more tolerant of sunlight than Camellia japonica cultivars. The recommendations were based on the Florida Friendly Landscaping principle of “Right Plant, Right Place”.
If you’re trying to find the right plants for you own yard, then you should check out the Florida Friendly Landscaping Interactive Plant Database. The database gives you plant selection options for each area of your yard based on location in the state, plant type, and soil and light conditions.
A very popular landscape shrub installed by both professionals and homeowners is Loropetalum or Chinese fringe. This shrub offers attractive foliage and flowers along with being evergreen.
When you visit a nursery to select this plant for your landscape, realize that there are now many selections of Loropetalum available. Learn about a few of the common selections in this recording of ‘In the Garden’, with UF/ IFAS Extension Escambia County Horticulture Agent Beth Bolles, so that you are successful at matching the appropriate plant with your landscape needs.
Air potato leaf beetle attacking the invasive air potato plant.
Air potatoes got you down? Have no fear, for the Air Potato Challenge is coming to Leon County!
Register now to attend the Air Potato Challenge event on May 18, 9 a.m. to 12 p.m. at the FAMU Center for Viticulture and Small Fruit Research (6361 Mahan Drive, Tallahassee, FL) and receive a supply of air potato beetles to use on your property.
After years of testing, air potato beetles became available as a biological control in 2012 to help combat the invasive herbaceous perennial air potato vine (Dioscorea bulbifera). Air potatoes arrived in south Florida from China in the early 1900s and have steadily crept north until they are now invading the Panhandle Region. Fortunately, air potato beetles have dietary requirements that are very specific, relying strictly upon air potatoes to complete their life cycles.
This is why a team of researchers and Extension agents have come together to help spread air potato beetles as a biological control strategy. Many agencies and counties are involved in this effort, including UF/IFAS Extension St. Lucie County, UF/IFAS Indian River Research and Education Center, the Florida Department of Agriculture Division of Plant Industry, the USDA, Florida Fish and Wildlife, UF/IFAS Extension Leon County, and Florida A&M University.
A healthy lawn is a joy to stroll, relax and play on. It can also be part of an environmentally friendly landscape. But, sometimes it can seem to be a mystery on how to achieve that lush, healthy lawn in the Florida environment. Since we have lots of sandy soils and experience long periods of warm and hot weather, many suppose that giving the lawn lots of water will help do the trick. Not so.
Photo credit: UF/IFAS.
But what harm can it cause to give the lawn plenty of water all the time? Isn’t that a good thing? No! Overwatering your lawn can lead to the following problems:
Development of fungal diseases (fungi love a moist environment!)
Increased insect pest pressure
More rapid thatch development
More weeds (those little emerging weed seedlings thrive on consistent moisture!)
Some weeds, like dollarweed and sedges, can be an indication of overwatering
A shallow root system when frequent, light watering is applied
Washing away of fertilizer down into the soil past the root system
Higher water bills.
Our lawns need, on average, about 1/2 to 3/4 “of water a week during the summer. This recommendation changes depending on soil type, shade, temperature, wind, and season. To figure out how long to run your sprinklers, watch this YouTube video from UF/IFAS.
We recommend running your automated system only when your lawn shows signs of needing water such as:
Bees, butterflies and other insects play important roles as pollinators in our environment. Over 50 major crops in the United States and at least 13 crops in Florida depend on honey bees. Many native plants in natural areas also depend on insect pollinators for reproduction. In Florida, over 300 bee species play a role in pollination!
Many factors affect the health of our pollinators. One of those factors we can easily control in our own landscapes is exposures to pesticides. How are bees and other pollinators exposed to pesticides? Here are some of the major routes:
Drift of pesticides sprayed in breezy/windy conditions
The erosion of contaminated topsoil blowing in the wind
Direct feeding on pollen and nectar of treated plants
Contact with pesticides that have blown onto plant surfaces
Contact with water transpired by leaves of treated plants
Pesticides that move down through the soil to affect ground dwelling bees and other insects
Did you know that bees become statically charged when they fly causing particles in the air to attract to them?
What are some ways that we can reduce the risk of exposure to pollinators in our landscapes?
Avoid treating areas containing flowering weeds/plants with insecticides. If you must treat your lawn with an insecticide, and it contains flowering weeds, mow the lawn and remove the flowers just before applying the insecticide.
If you must apply a systemic insecticide to your lawn, leave a buffer strip of several feet between the lawn and the border of landscape beds with flowering plants. This will prevent the flowering plants from up taking the systemic product.
Postpone any insecticide treatment until after all blooms have fallen from flowering ornamentals. Never apply an insecticide to blooms or flowering plants.
Avoid the use of neonicotinoids as this class of insecticides can be more toxic to bees than other classes of insecticides. There are many effective alternatives.
