15 Jun Plant stress is pandemic in Oklahoma because of heavy rain.
With the advent of the heavy rains we’ve been having in Oklahoma, new plants may be showing signs of stress. Things to look for are yellowing of leaves and/or brownish spots, wilted leaves and quite possibly defoliation. Also, if the leaves are turning black or are showing a white fuzzy like texture on them this can be a symptom of fungus. If this is the case an off-the-shelf fungicide from any box-store should solve the problem for the most part. Be sure to apply the fungicide to the surrounding soil as well as the affected plants. The fungus spreads in a moist environment. You may have observed in times past a black layer on exposed soil in your yard. This is a fungus, and fungus can affect your turf grasses as well, especially shade grasses so applying fungicide on your turf can be a simple fix for an unsightly problem. Fungus lowers the ph of its environment creating an acidic condition that it thrives in, the lower ph can literately burn trees, shrubs, and turf to death.
Once the rains moderates, you may become the guilty party for overwatering your trees and shrubs.
Here are some watering pointers…
New plants need to be kept moist, but too much water can kill them before they even put down roots! It is a misnomer that a little water is good so a bunch of water is better. The roots need to breathe so over-saturated soils can suffocate the plant and cause root-rot. So allow for some drying time between watering.
If your new plant is a tree, it will require quite a bit of water to start. Turn your hose pressure way down to a drip or a small trickle at best and place the open end of the hose near the trunk. Allow this to soak in for up to an hour each day, this gives the water time to go deep down instead of just moistening the surface soil. If your city is under water rationing, you may only be able to use the hose method every other day, but hand watering, with a can, or large bucket with holes poked low in the sides, can have a similar effect and is legal.
Bed Plants and Shrubs
Use the same method as for trees, but for a much more limited time, from five to ten minutes tops, until the soil is damp down to at least one to two inches underground level. Do this daily.
For potted plants, the soil tends to dry out more, so use a hose, or watering can saturate the pot until water seeps from the weep holes in the bottom of the pot. Do this for all of your potted plants, then come back and water each one a second time. The initial watering readies the soil by causing it to swell, it’s similar to a sponge, a moist sponge absorbs water more quickly than a dry one, this allows the second watering to go to the plant.
Potted plants on the ground tend to fare better than elevated, or suspended plants when the temps are hot. Move your potted friends to ground level, where there is partial shade for best protection and to help maintain adequate soil moisture.
Plants that have been in your landscape for years need love too! For trees, follow the soak method a few times a week. Typically established trees have tap roots running deep into the soil that will find water, but every little bit helps.
There is an exception, conifers with scaly leaves, such as firs and pines should be sprayed from the outside, so that water runs on top of the leaves, from the top down. They take in much of their moisture this way and it acts much the same as giving them a fluid from an IV, getting into the circulation of the tree sooner.
Following these guidelines should help you keep your plants healthy, but remember, no landscaper or nursery will be able to guarantee plants in harsh conditions such as record heat or rain falls.