UACES Facebook May Garden Checklist Part II
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May Garden Checklist Part II

May Garden Checklist Part II


 In this week’s article, I want to mention more things gardeners need to be considering for May. The following is a garden checklist:

  • Don’t forget about bulbs for summer foliage and flowers.  Most nurseries have both dried bulbs and growing plants.  Look for caladiums, elephant ears, cannas, gladiolas and dahlias.  Most summer bulbs like warm soil before they really start to grow.
  • To prevent early blight on tomatoes, start spraying with a fungicide such as chlorothalonil or mancozeb when first bloom clusters are noticed. This disease causing fungus can stay in the soil for several years. Mulching will help some, which prevents the splashing of soil onto the lower leaves. Planting tomatoes in a new spot will help, but contaminating your new garden site can happen so quickly. This disease is transferred to a new garden by wind-blown spores, contaminated tools and shoes, buying diseased plants, or chewing insects.
  • Be on the look out for new hatches of bagworms on your junipers. This time of year they are no larger than ¼ inch in length and very easy to control with Bt. As the season progresses they will become 1 ½ inch in length and will only respond to insecticides such as acephate, bifenthrin, Sevin or permethrin.
  • If you have grassy weeds growing in your groundcover, iris beds or flower beds, this is a good time to use one of the grass-specific herbicides.  These products kill grass without hurting most flowers and groundcovers.  Using them early will give a better kill and you won’t have the dead grass to take away from the beauty of the flowers. Some names of these products are Fusilade, Ornamec, Segment and Envoy. In our trials, Fusilade (fluazifop-P) has been the most effective for bermudagrass. Always read and follow label directions.
  • Check your roses for rose slugs feeding on the foliage. These pests skeletonize the leaves. Insecticides that control rose slugs are insecticidal soap, Sevin, malathion, permethrin and cyfluthrin. Only apply an insecticide when rose slugs are present.
  • Yellow leaves on azaleas are a sign of nutrient deficiency. If new leaves are yellow with green veins, the plant is not getting enough iron. Iron deficiency is a common problem of azaleas grown in soil that isn’t acid enough. Use acidifying type of fertilizer or sulfur to alter the pH. Test soil to see what your pH is. If older leaves of azaleas are turning yellow, the problem is lack of nitrogen. This is corrected by fertilizing.  
  • Squash vine borers cause squash plants to suddenly wilt and die. Although the squash plant will die once symptoms are visible, you can prevent infestations by keeping plants treated with bifenthrin or malathion once every 7 days. Target insecticide to the base of the plant because this is where the borers make their entry way.
  • Keep mums pinched back monthly to keep them more compact. Stop pinching by mid-July to allow flower buds to form. If allowed to grow on their own, they will get top-heavy and sparse.
  • If you have black ants clinging on your peony blooms, don’t use the bug spray.  They are snacking on the sweet fluid produced by the buds as they open.  Contrary to popular belief, ants are not necessary for the blooms to open.  However, peonies do benefit from the ants’ presence because, while they are feeding on the nectar, they ward off other insects that might want to eat the peony.
  • All shrubs should be showing signs of growth by now, even crepe myrtle. Take inventory of any plants that were not doing well last fall and see how they are doing. Corrective pruning or replanting may have to be done.
  • 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 May and again in July. Permethrin works 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. 

For more information on gardening, contact the University of Arkansas System Division of Agriculture Baxter County Extension office at 425-2335.

By Mark Keaton
County Extension Agent - Staff Chair
The Cooperative Extension Service
U of A System Division of Agriculture

Media Contact: Mark Keaton
County Extension Agent - Staff Chair
U of A Division of Agriculture
Cooperative Extension Service
3 East 9th St. Mountain Home AR 72653
(870) 425-2335


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