It has been a frustrating year for gardeners. The spring gardens sputtered out early and deflated the enthusiasm for planning a fall garden.
It is OK. This too shall pass. We will adapt to make it work.
I know it is easier to stay inside and cool than go outside and mow the lawn, but if the grass gets too tall you will be scalping it instead of mowing it. Late in the day seems the best time of day to mow for your sake as well as the lawn.
The meteorologists have been talking about the string of consecutive days above 90 degrees Fahrenheit. If rainfall is adequate, this is a corn farmer’s dream. Without adequate rainfall it is another matter entirely. The high temperatures are resulting in symptoms on our plants that we are not used to seeing.
"Help, my grapefruit are not growing. They are staying small!"
That is to be expected. Don’t panic. The leaves of your tree have to produce enough energy to meet their own needs and then produce enough surplus food to meet the needs of the twigs, branches, trunk and roots. Anything left over after that is free to be put into the fruit.
Let us start with a citrus tree with adequate soil moisture, warm temperatures and relatively low humidity. The plant is running at a good energy profit. Fruit are putting on size. What slows down this process? Lack of adequate water is the fastest way to bring everything to a halt, but other things influence productivity as well. High temperature causes the amount of energy consumed by a plant to increase as respiration rates increase. Every 18 degree F increase in temperature doubles the cost of biological processes. Humidity increases slow down photosynthesis by slowing down the rate of water transpiration. Transpiration of water cools the plant and keeps leaf temperatures cool enough for photosynthesis to proceed. The humidity inside a living leaf is always 100 percent. Fast transpiration rates happen when humidity of the air outside the plant is low. This results in the most cooling effects for the leaves. High humidity slows the transpiration rate. Less heat is carried off by the water that is transpired and the leaves heat up, consuming more of the energy they produce. Less energy is available to go into fruit production.
So high humidity and high temperatures result is less profit from the leaves and therefore less investment in the fruit. Once temperatures decline, humidity drops and rainfall returns, the fruit will start growing again.
The same thing has happened with indeterminate tomato plants. All the energy that would have gone to producing fruit has instead been consumed by the plant just trying to meet its own daily needs. When temperatures moderate, the plants will start producing tomatoes again. More fertilizer will not fix this problem. Too much fertilizer can make it much worse. We just have to ride it out.
Some of our citrus fruit is showing yellow coloring on the direct-sunlight-exposed surface of immature fruit. Yep, it is sunburn on the fruit. If the fruit was growing the new cells would replace the damaged cells and the symptom would not appear. The symptom does not affect the quality of the fruit beneath the rind. These fruit will be perfectly good to eat once they mature.
A word about water: How is the rainfall for the year for Bryan County? It depends on where you are. And I don’t mean just Pembroke versus Richmond Hill. So far this year when Richmond Hill gets rain, Fancy Hall does not see a drop. Inundating rainfall at 17 and 144 requires the windshield wipers on high, while it is bone dry at the Bryan County Administration Building. I even had rainfall at the entrance to my subdivision and no rain when I got to my home. I have long said that gardening in coastal Georgia is hydroponics. The plants only get what you give them. The sand is just there to hold them up.
This year coastal gardeners need to keep the Serenity Prayer in mind.