With the spring season still fresh on our minds, now is the time to reflect on some common disease and pest problems that occur in the garden center, recognize which problems touched your store, and identify solutions to quickly treat and control these problems in the future.
Ideal solutions for the retail environment will be fast and effective with a short REI, have labels including edibles and ornamentals, present no or minimal odor and residue, bring no risk of burn or other phyto, and will not present a residual bee hazard. It’s a tall order, but we have solutions that fit the bill for some of the most common diseases and pests.
The main foliar disease encountered in garden centers is Botrytis. This ubiquitous disease requires humid/moist conditions and can attack both dying and healthy foliage and floral tissue, producing characteristic gray, fluffy sporulation. Botrytis attacks healthy tissue with as little as four hours of free moisture. Therefore, avoid wet foliage and flowers going into night to greatly reduce this risk. Bloom safe options for control on certain edibles and ornamentals include Affirm (no herbs or leafy greens) and ZeroTol 2.0. Cease and Triathlon BA are excellent choices for prevention. Pageant Intrinsic is effective and includes tomatoes on the label, but also presents a 12-hour REI. Mural is a new product that also presents strong control of Botrytis. The Mural label includes many cucurbits and fruiting vegetables on the label, though it also requires a 12-hour REI. Emblem is another new product that includes many edibles on the label and provides strong, bloom safe control of Botrytis (see label for a few exceptions). Emblem does come with a 12-hour REI.
Powdery mildew also occurs in the garden center, especially on sensitive crops like gerbera, dahlia, and calibrachoa. Look for white film-like sporulation on the upper leaf surfaces. Powdery mildew develops best under high humidity with dry tissue. Decrease humidity to avoid the disease. Affirm provides good curative control (no herbs or leafy greens), while Regalia PTO does a spectacular job for prevention. Regalia PTO is not labeled for edibles in NY (sub Cease or Triathlon BA).
Downy mildew remains a serious problem for impatiens in many areas of the country. If you continue to offer Impatiens walleriana, purchase products from growers practicing very strong prevention, which should include a drench of Subdue MAXX just before the plants ship to your garden