Wow! Rain, rain, rain. While we never know for certain until we can look back, it looks like the drought of 2011-2015 may now be one for the history books. It is true that one rainy period cannot possibly undo all the damage that has been done to our landscapes but this is a promising step in the right direction. With a forecast for several more inches looming over the next week or so, we can expect there to be some negative fallout associated with this much rain, even if it was desperately needed.
Root saturation/lack of oxygen may lead to yellowing leaves, especially in young plantings. We will also likely see an increase in foliar disease issues. These two issues are often hard to tell apart. In general, the whole plant is more likely to be affected if it is a water-logged soil issue, while yellowing on one part of the plant is more likely to indicate disease.
If it’s a water-logged soil you are dealing with, your options are limited. If you’ve already mulched, it can help to rake the mulch away from the plant to encourage evaporation. If the soil is crusted over, it can also help to very lightly cultivate the surface as this can also help the issue.
You will also need to keep moisture management in mind from another perspective. If roots can’t get enough oxygen, they will die back in a short period of time, leaving your plant with a smaller root system than it had just a few days ago. The take home here is some plants may wilt from lack of water much quicker than you might normally expect. It is sometimes difficult to judge as wet wilt and dry wilt can look very similar but it’s impossible for me to give much direction other than encouraging you to take a close look at the soil and your plants on a regular basis.
Disease is also likely to be a problem. Most diseases will be fungal in nature so look for products labeled with the word “Fungicide”. There are dozens and dozens on the market for a variety of plants and diseases. It is very important to read the label so you’re confident in using a product that is labeled for your specific plant.
Fungicides tend to work better as a preventative treatment rather than a curative one. Don’t expect miracles with one or two sprays if your plants are already in severe decline. If leaves are showing significant damage, it can often be in your best interest to prune them off and removing them from the area so the disease is less likely to be transmitted to other plants.
I would also suggest fertilizing your lawn with care while it is still very rainy. While many of you have been waiting for good growing conditions, you don’t want to create a situation where your turf is growing out of control with you unable to get your mower out of the shed.
For more information of this or any other horticultural topic, you can contact Keith Reed, the Horticulturist in the Payne County Extension office. Keith can be reached via email at firstname.lastname@example.org, phone at 405-747-8320, or in person at the Payne County Extension office, located at 315 W. 6th in Stillwater.
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