Bearded iris has fungal problems
How do I treat fungal leafspot on my bearded iris? All of them are infected.
Cut off all infected parts of the foliage and remove from the site. The spores overwinter on old leaves and flower stalks, so clean these up in fall and spring. The fungus thrives in mild, damp conditions. Provide full sun and good air circulation. Don’t water overhead. (They rarely need watering and tolerate droughts easily.) A fungicide, such as one containing chlorothanonil, can be sprayed as a preventative. Because they have a waxy coating on their leaves, mix a spreader-sticker into the spray to help it adhere better. Before we get our vegetable transplants into the ground, how can we ensure the soil is safe to grow edibles?
Primarily, test the soil for lead. Go to the soil testing icon on the Home and Garden Information Center website below. It links to fact sheets about selecting and using soil testing labs, how to take a soil sample, and a list of labs in our region. Some labs include lead in the basic soil test. Select a lab, download their form, and submit your soil samples with a check to the lab. A cup of soil is needed for each garden area or bed that you test. You can use a plastic sandwich bag to send each soil sample. Tip: Dry out the soil before mailing. It weighs less, so postage will be less, too. Soil test results give recommendations to adjust pH and nutrient deficiencies. If lead is found, search “lead” on our website for further direction. University of Maryland Extension’s Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click “Ask Maryland’s Gardening Experts” to send questions and photos.
Digging Deeper
Just when cucumbers seem on the way, the whole plant can wilt and cucumber dreams fizzle. Watering doesn’t reverse this sudden wilt, because drought is not the problem. It’s brought on by striped or spotted 1⁄4 –inch cucumber beetles, black and yellow with three long black stripes or 12 black spots, respectively. As larvae and adults, they feed on over 250 plant species, but adults do the worst damage when their feeding transmits cucurbit bacterial wilt to cucumbers, cantaloupes, muskmelons, squash or pumpkins. To diagnose bacterial wilt, cut a wilted stem and touch the cut ends together. Slowly pull apart. Sap mixed with bacterial ooze will string out in fine strands. Cut ends may also ooze a milky substance when placed in water. Infected plants cannot be saved. To avoid cucumber wilt, go to the Home and Garden Information Center website and use the search box. It is not too late to plant a second crop of cucumber and squash.