Wet, Humid Weather Aids Fungus, Blight
I think there is an old saying that if it rains on the first day of June, it is going to rain 15 days in June. I don’t know if that is true or not but with the spotty showers we are getting on a regular basis it could be possible. This humid, overcast and rainy weather that we have been experiencing over the few days creates a fungus growing environment in the garden and lawn.
I have received several calls and looked at several disease/fungus problems over the last week that I would like to share. In lawns I have received several calls about a grey colored mold growing on the leaves of grass. This is called slime mold and really is not a problem for the grass other than being an eyesore. Warm dry weather and regular mowing will clear this fungus up. I have also seen large patch fungus in several lawns around the county. Large Patch is a severe disease in lawns and is identified as large irregular shaped circular areas in lawns that appear to be dead or dying and can be further identified by distinct yellow or orange leaf colors on the edges of the affected areas. There are treatments available for large patch, all of which are not cheap – Systar, ProStar, and Head-way will knock out the fungus. The problem with this fungus is that after you have killed the actively growing fungus you are still left with large irregular dead spots in your lawn. Rust is another fungus that I have seen on lawns this year and if left untreated can cause thinning and death to lawn grasses. Rust can be identified on the blades of grass and will stain with a reddish color if touched. Rust Fungus can be treated by simply fertilizing your lawn or by using a fungicide that contains chlorothalonil.
I have also received several calls on diseases affecting tomatoes in the last week. One disease is early blight, which causes yellowing of lower leaves and branches on the tomato plants. This disease can be treated with several fungicides but tomatoes generally will outgrow this fungus over the course of the growing season. I always tell people that I talk to about vegetables especially tomatoes and squash that you need to be spraying preventively with a couple of different fungicides like Chlorothalonil, mancozeb, or azoxystrobin. If during the growing season you have a tomato plant in a group of plants that wilts down and just dies the best thing to do is get that plant out of the garden and bury it off site, more than likely this is caused by one of the wilt viruses. Viruses in vegetables are not treatable but they are spreadable and could wipe out your crop if not removed from the area. Another good tip to remember is if you are handling a diseased plant be careful not to touch or handle any other plants before washing your hands thoroughly.
The last vegetable growing class of the summer will be held on June 15 at the Multipurpose Building in Coffeeville at 6 p.m. We will discuss marketing your produce and proper handling procedures for vegetables.