|Planted Asian Cucumbers from seed and they have been climbing up on the support just fine, but now the leaves are turning grey and have a powdery look to the leaves and the plant dies in just a few days. What can I do to save the ones that are still living? Love cucumbers and never had this happen. I bought a fungacide for gardens today and wonder if there is a better time to put it on. Help!|
|I?m sorry you?re having troubles with your cucumbers. Cucumber plants are susceptible to powdery mildew. Powdery mildew appears as a whitish/greyish powder on foliage. Powdery mildew is unique among plant diseases in that it doesn't require a wet leaf surface to spread. It can thus thrive during hot, dry weather. The first line of defense is to grow resistant varieties. Here are some general cultural practices for helping control powdery mildew. Make sure that your plants are getting enough direct sunlight. (Eight to ten hours a day is generally the minimum for plants that flower or bear fruit.) You'll also want to make sure that there's enough room between plants for air to circulate freely. Overcrowding not only makes plants more susceptible to diseases, if leaves touch other plants, those diseases can easily be spread. The general advice to inhibit the spread of fungal diseases is to avoid wetting leaf surfaces. In the case of powdery mildew, you can actually inhibit infection with periodic strong sprays of water (not so strong as to damage the plant), but first remove any infested leaves and dispose of them in the trash. At the end of the season, rake up and dispose of all plant material in the trash as powdery mildew can overwinter to rear its head again. Before applying any fungicide, read the label carefully and make sure it states that it?s okay to apply it to edible crops. Follow directions exactly.
One other thing about wilting cuke leaves. In hot weather, their big leaf surfaces may transpire more moisture during the day than the root system can take up. They may recover during the night and not be wilted in the morning. But we often see the wilted leaves during the day and automatically apply more water, which can literally drown the roots. Roots need oxygen to survive. Check your plants in the morning to see if this is the problem. If they?ve recovered from wilt, don?t overwater. I hope this info helps!