It has been a tale of two summers. The first part of our Oklahoma summer was unusually moderate in temperature and wet with record setting rains. The second summer arrived about two weeks ago and has been unleashing a study stream of triple digit blazing hot summer weather. It is amazing how quickly the transition occurred and how soon the change impacts we humans and our trees, shrubs and gardens. We got away most of this summer with limited watering as Mother Nature was providing the needed moisture on a regular basis. Now in less than two weeks of the punishing and searing heat of an Oklahoma August many of our mature and established trees are shedding leaves. They drop a few leaves to thousands of leaves to adjust the canopy they are supporting to the available moisture and root system.
Driving around Oklahoma this last weekend I saw many young trees planted this year or last that have gone from looking good two weeks ago to all brown or largely brown foliage. The shock of the intense heat and dry hot winds has blistered these new trees and shrubs that do not have established roots deeper in the ground where moisture is still available. You may have been able to get by without watering or sprinklers through most of July, a couple of months later than in normal years. We are definitely now in a “water” or suffer near death cycle for many of our color plants, container gardens, hanging baskets and recently planted trees or shrubs.
You can still add some container gardens to your porch or patio. I would refrain from planting trees, shrubs and flowerbeds in this heat unless you soak them in, mulch the top of the soil and are prepared and committed to regular watering for the rest of this growing season. It is amazing how quickly the topsoil dries out once we get these blazing hot August temperatures. Concentrate your garden time while this hot weather lingers on watering and mulching your existing plantings to survive and grow. Then you can tackle new plantings after the weather cools a little as we approach fall season weather.
In watching some of the PGA golf tournament hosted by our good neighbors over at Tulsa this weekend on television you could see how the players and crowds were sweating and burning. As hot as they were they could towel off, pour water over their heads or go stand in front of fans or go into air-conditioned tents. Your turf, flowers and trees cannot move to get that relief and in this weather they are dependent on you to bring water and relief to them. Trees and shrubs can adjust how much plant they have to support by dropping leaves or even whole branches as they fight for survival but you can truly make a difference with regular watering.
When you water, water thoroughly so that you will soak the soil to a depth of four to eight inches instead of just squirting the plants or top of the soil. You can add polymer water absorbing crystals to your soil to help the soil retain water longer and reduce watering. I often mention mulching the top of your flowerbeds and container gardens and a two or three inch thick top cover of bark mulch, straw or natural hulls like cottonseed hulls, cocoa hulls or pecan hulls will cool the soil and reduce evaporation of soil moisture. Mulching will often cut watering in half while producing happier plants. Hand watering with a water hose or strategically placed overhead sprinklers can provide the needed soaking.
Use of weeping soaker hoses or installation of drip irrigation can help you grow better plants while delivering the water most effectively to the root zone of the plants. A good system can reduce water use by fifty to seventy-five per cent while growing better plants. One of the best ways to water new trees or large shrub plantings for their first season or two is a reinforced plastic bag from New Zealand called a Tree Gator that drips water around your young tree. You fill the fourteen or twenty gallon bag with water once or twice a week or as needed with a waterhose and it will slowly weep out around the new tree over an eight to twelve hour period so that the tree gets the full use of all the water.
It is time to start preparation and planting for your fall vegetable garden. You can also do soil preparation for winter fescue planting which should start around mid September. We are approaching the season to apply pre-emergent weed and feed products to your lawn to kill winter weeds before they germinate and we will explore that subject more in our next column.
This hot summer weather is resulting in a surge of insect problems. Red spider mites and scale seem to be especially active so be on the lookout for pest problems and visit your local garden center to determine the best chemical or other approach to keep them under control in your garden. The middle part of the day and afternoons can be too hot to enjoy being in the garden. We have fairly nice weather early in the morning and as we approach sunset so those are best times to enjoy the garden in August.
Rodd's Seeds of Wisdom 