George Wedel |
The number one topic of gardeners this week has been the weather. Wildly fluctuating temperatures and how much or little rain has fallen in your neighborhood. Some localities received several inches of rain 10 days ago; others less than an inch with temperature swings from the 60s to near 90 degrees. The up and down weather has many green-thumbers scrambling to provide plants what they need to stay healthy. This week at Wedel's Plant Diagnostic Center we have been very busy helping folks with garden and landscape challenges that you should be on the look-out for in your lawn and gardens.
Hard maples, both Norway and Sugar, are dropping green leaves. The quantity of falling leaves is quite alarming to some homeowners. The culprits are Petiole Borer or Leaf Stalk Borer. The Leaf Stalk Borer tunnels in Norway Maple leaf stalks, causing a half-inch wound which weakens the stem and sends the leaves to the ground. Sugar Maples are very prone to Petiole Borers. Petiole Borers tunnel into Sugar Maple leaf stalks about one-half inch from the leaf. Control these pests on maple trees next year with sprays of 10% Permethrin, first on May 10th and then again on May 21st. An easier solution is to apply Systemic Insect Control at base of tree trunk in October.
Check all dogwood trees today for Dogwood Anthracnose infection. Signs of infection are wilting leaves that soon turn brown. Infected branches will die rapidly. Prune out all infected branches. Sterilize pruners with Consan between cuts. Apply tree wound paint to all cuts. Then spray tree with Halt Fungicide. Prevent first time infections with a spray schedule of Halt Fungicide every two weeks April 21st to June 15th. Use Maneb Fungicide on dogwoods every three weeks August 10th through October 7th. Remove competitive grasses over root zone of dogwood trees and keep mulched with two inches of cedar wood chips. If necessary, prune nearby trees to allow morning sun to penetrate to dogwoods. Apply Fertilome Systemic Soil Insect Drench to help with borer control, at base of tree in spring or fall. Fertilize dogwood trees in March and October with Holly Tone.
Anthracnose disease is running wild among maple, oak, and sycamore trees. The rainy weather makes perfect conditions for anthracnose to spread from one tree to the next. Brown, curled and falling leaves are the most obvious signs. Anthracnose can be prevented if trees are sprayed with Halt Fungicide as they leaf out. To prevent further infection, spray trees now with Halt. To help infected trees recover, fertilize each autumn with Tree Tone and water well during the summer. Well-fed, healthy trees will grow faster and heal over branch cankers that harbor anthracnose spores.
Euonymus Oyster Shell Scale and Juniper Scale is active; control measures should be taken now. Spray with Horticultural Spray Oil mixed with Malathion. Apply Systemic Insect Control on soil at base of plants to control later scale infections. Feed infected plants yearly with Tree Tone.
Soft shell scales are active on many trees this spring and what a mess they make. Dripping honeydew, secreted by the scale insects, coats everything under the infected tree; decks, cars, walks etc. It then molds into a gray-black sticky mess. Prevent soft shelled scales and their damage by using Fertilome Systemic Soil Insect Drench or Acephate Tree Trunk Implants then spray any reachable branches with horticultural oil spray mixed with malathion.
We don't have to look very far to see aphid damage on shrubs, trees, and perennials. Curled and deformed leaves on the ends of branches are tell-tale signs. Control aphids on ornamental plants with Malathion, Pyrethrin or Insecticidal Soap.
Hollyhock plants are showing signs of rust infection on stems and leaves. Recent weather conditions have promoted this problem, with rust spots so numerous that they run together and destroy the entire leaf. Remove the most seriously infected leaves, then spray with Banner Fungicide. Banner will also control mildew and leaf spot as well as rust on many other perennial plants.
Look over honeysuckle shrubs and vines, burning bush, and Snowball Viburnum shrubs for aphid infestation. Curled, deformed, and stunted black leaves are signs of aphid feeding. Control aphids on these and other shrubs and vines with sprays of pyrethrin and the application of Fertilome Systemic Soil Insect Drench.
Warm, damp weather promotes leaf spots, gray mold, and brown rot on strawberry plants and fruit. Control strawberry diseases with sprays of Captan.
Spittle bugs are beginning to feed on many perennial plants and new growth of pines. Control Spittle bugs with 10% Permethrin.
Honeylocust plant bugs will be feeding soon. Spray locust trees now and again in two weeks with 10% permethrin and apply Fertilome Systemic Soil Insect Drench to keep trees clean.
Lilac borer adults are out and looking for plants to lay eggs on. The adult borer resembles a wasp and lays its eggs on plants that are under stress. The eggs hatch into very destructive borers, which kill branches and even entire plants. Control Lilac borers with sprays of 38 Plus to trunks and lower branches every three weeks throughout the growing season or Fertilome Systemic Soil Insect Drench now and again in October for twelve-month control.
Grass plants are now producing seed stalks and heads; this is normal for turf grass plants. During the three to four weeks that grass produces seed heads, lawn appearance can decline. To keep turf looking its best, mow with a sharp blade, see that one-half inch of water is applied every four days, and mow every four days. Apply the second feeding for the year to encourage growth.
Haven't had time to kill the broadleaf weeds in your lawn? Don't despair. Weed Free Zone Lawn Weed Killer can be applied now with excellent results.
Lawn diseases that are active now, such as red thread, powdery mildew, dollar spot, and leaf spot, can ruin a lawn if a control material is not applied to check their spread. Apply Scotts Granular Lawn Fungus Control or Banner spray fungicide now for excellent lawn disease protection.
Mildew is abundant on roses, lilacs, and azaleas. Control mildew on these plants with Funginex.
Ants, millipedes, sowbugs, earwigs, and ticks all seem to be present in greater numbers than usual. Sprays of 38 Plus or an application of Bifenthrin granules will rid outside areas of these pests.
Oak trees, rhododendrons, and azaleas with leaves that lack a dark green color and exhibit a blotchy, light yellow appearance, no doubt, are suffering from iron chlorosis. A mixture of Granular Iron and Sulfur should be applied now over the plant's root zone. Be sure to fertilize oaks with Tree Tone every October and rhododendrons, azaleas, and hollies each spring and fall with Holly Tone.
If time didn't allow for an early spring feeding for your perennial beds, don't delay any longer. Spring feeding perennial flowers will reap great benefits of more blooms and larger plants. Scatter one cup of Plant Tone around each perennial clump, then soak well with Fertilome Blooming 9-59-8 water-soluble plant food.
Tulip and hyacinth plantings that are ripe may be lifted now. Lift bulbs carefully, cut the stems off of the top of bulbs, remove all soil, and peel off small bulblets. Put bulbs in a paper sack with pre-mixed Bonide Bulb Dust and shake gently to coat each bulb. Store for the summer in mesh bags in a well-ventilated area. Proper care and storage will assure good tulip and hyacinth bulbs for fall planting and good blooms next spring.
