Troubleshooting

first_imgBy Bob WesterfieldUniversity of GeorgiaThe muggy heat makes working in the landscape less appealing thanit was in the spring. But insect, disease and other plantproblems need attending to.To keep your landscape looking its best, be a Sherlock Holmes inyour yard. Frequent visits to keep an eye on things is often allyou need to detect problems before they get too big.A trowel, a white index card and perhaps a hand pruner will helpyou with your landscape detective work.First, visit your annuals or herbaceous perennials. These plantsusually need the most immediate attention. Are they healthy,green and strong or spindly, yellow and weak? Perhaps they need alittle fertilizer. Annuals, in particular, benefit from light,frequent applications.Look closelyBe careful, though. Look closely. Yellowing of these plants canalso mean too much water, and recent rains have kept the soilfairly wet.Dig down a little to see how wet the soil is and how well it’sdraining. Heavy, wet soils can play havoc on many landscapeplants and may be hard to remedy without renovating the bed.Look at the blooms of these plants. Deadheading, or removingspent flowers, will help keep them blooming all summer. Check theblooms, too, for signs of insects or disease.Look carefully at the foliage on all plants. Are the leavesspotted or riddled with holes? Are they speckled, bronze-coloredor different from the way you remembered?Leaf spotsLeaf spots can be caused by insects or disease. Usually, if it’sdisease, a yellow or purple halo will be around the dark spot.You may need to use a fungicide. Sometimes, improving the aircirculation by lightly pruning will improve a plant’s health, too.Insect damage may appear as solid, blackish-brown spots, chewedareas or speckled leaves. Be sure to look at the undersides ofthe leaves. Many insects will feed and hide there.Properly identifying the insect is the key in selecting thecorrect control. Remember, there are far more beneficial insectsout there than bad guys. Beneficials do an outstanding job ofkeeping damaging insects at bay on their own.Buy a good insect-ID book and learn how to tell the good bugsfrom the bad. Treat plants only when pests are causing moredamage than you can live with.Hard to seeSome insects are so tiny they’re hard to see. This is where yourwhite index card can help. If you see speckled or off-coloredfoliage and suspect insects but can’t see any, shake the leavesbriskly over the index card. You may see tiny red specks calledspider mites.Spider mites can build up heavy infestations quickly ifconditions are right. To control these pests, use a productlabeled for mite control.Check azaleas for off-colored foliage, too. A common summerproblem is lace bugs, which feed on the undersides of the leavesof azaleas, cotoneasters and other plants. They have manygenerations of offspring, so keep a watch and control this oneall summer.Chewing damageChewing damage on leaves often indicates another type of insectdamage. This can be caused by many insects, including Japanesebeetles, leaf beetles, snails and slugs.Once you know which culprit is munching on your plants, selectthe appropriate control. Insects are usually easier to kill whenthey’re young than when they’re mature.The University of Georgia Extension Service office in your countycan help you figure out what caused your landscape problem andthe best control measure.County agents have special diagnostic tools and resources to helpthem solve almost any landscape problem. Be sure to describe thedamage accurately.Better yet, bring in a fresh sample. While you’re at the countyagent’s office, pick up a few of their many brochures on insectand disease control in the landscape.(Bob Westerfield is an extension consumer horticulturist withthe University of Georgia College of Agricultural andEnvironmental Sciences.)last_img