Despite our topsy-turvy April weather, May promises to be a busy month. As soon as the soil warmed up, plants appeared out of nowhere and demanded our attention. Weeds are in abundance everywhere, lawn turf is greening up, spring shrubs are already in peak bloom, and houseplants seem to want to go outdoors. And there are new and exciting as well as true and tested plants available everywhere.
So here are a few “to do” gardening tips in May:
• Keep a clean garden. Mulch around plants to help maintain moisture and discourage weeds. Organic mulches break down slowly, releasing nutrients into the soil. Mulch can also cut down on soil borne diseases such as tomato blight.
• Herb gardens are an easy way to have an ample supply of fresh herbs for cooking. Many are perennials and some are evergreen and can be used in the landscape as well as to eat. Rosemary is a semi-shrub and thyme makes an attractive evergreen ground cover in full sun. Be careful with pesticides around herbs — if you are going to eat them!
• Prune spring flowering shrubs as soon as the flowers fade. If you prune in the fall or winter, you will remove next season’s flower buds.
• Check azaleas for lacebugs. This small sucking insect prefers to feed on azaleas or pyracantha but can spill over onto any kind of adjacent plants. The leaves of infested plants are yellowed and stippled on top. Black deposits from the lacebug are left on the underside of the leaves. To control, apply acephate, imidacloprid, bifenthrin or permethrin according to label directions.
• Fertilize warm-season lawns — zoysia and bermuda — as soon as they are totally greened up. Use a high nitrogen fertilizer. Most of the weeds that have been blooming are winter weeds and should be on their way out. Start watching for summer weeds — crabgrass and nutgrass — and catch them as they emerge and try to stop their spread.
• Spring flowering bulb foliage needs to remain as long as possible (minimum of six to eight weeks after blooming). Foliage can be removed at first signs of yellowing. As it begins to yellow, it is a good time to dig and divide clumps of overcrowded bulbs.
• Dogwood, flowering plum, ornamental cherry, crabapple and related plants are prone to borers. Borers usually enter the trunks of these trees at soil line and can cause death in one or two seasons. A preventative control for borers is an application of insecticide applied to the trunk of trees in early May and repeated at six-week intervals two to three times. Permethrin or bifenthrin work well in protecting these valuable ornamental specimen trees. Also, applying a 2-3 inch mulch around these ornamentals helps prevent damage to the trunk from lawnmowers and string line trimmers which helps prevent borers too.
• Houseplants can safely be moved outside if you haven’t already done so. Expose plants to sunlight gradually.
• When pansies and violas start to fade, replace them with summer annuals for summer color. There are lots of excellent annuals to choose from.
Jayson McGaugh is the Sebastian County Cooperative Extension agent. Have questions about lawn, garden or other horticulture related issues? The Sebastian County Extension Service can help with offices in Barling and Greenwood. Call (479) 484-7737 for answers to horticulture questions.