How to keep the stress out of both the gardener and the plants in summer hot subtropical climates.
(Apart from the obvious answer, that is to give the gardener a large cocktail.)
When the temperatures here in Texas is around 95°F (35 degrees°C) I’ll leave my garden to go on holiday home to our cabin on Gaare, Orust in Sweden. I don’t feel fully comfortable with the thought of leaving because of a lot of the plants in the garden are still newly established.
Apart from some very few windy and cold days in the winter, it is in July and August that your garden in Texas needs you the most.
It’s obvious that plants need to be watered frequently at this time of the year, but now when the plants are weakened by the intense heat they are also very vulnerable to diseases and insect pests.
What can you do to take most of the stress from both the gardener and the plants?
The summer annuals (zinnia, sunflowers, cleome, nicotiana) planted early in this spring are withering down now. Mine are getting some mildew, they start to get lanky, and if it had not been for the beneficial insects who need all the nectar they can get I suppose I would have cleared away most of them.
Fruit trees and other trees need at least one heavy watering each week. Younger and newly planted trees need watering more often. The best way to watering trees is to drip irrigate them for a couple of hours every week. Make sure that the soil around the tree is soaked around 15-20 inches down. Be sure that they have a good blanket of mulch around the trunks to keep weed out and moisture in. Do not add more than 2 inches of mulch at the same time since it may prevent the roots closest to the soil surface to do their job absorbing oxygen. You do not want to slowly suffocate your trees? Do not forget that the roots of a tree are at least twice as wide as the tree crown, so make sure you not only water up to the tree trunk.
Shrubs will need regular watering. Even the well-established ones. I water the shrubs at least twice a week at this time. Approximately 1 bucket each. (5 Gallons) Keep in mind that azalea is especially vulnerable to drought because of their shallow roots.
Roses needs moist soil. Not dry and not wet. At least that’s ideal. Mine are sometimes try and sometimes wet. And they sulk a lot in July and the first weeks of August. A horticulture oil like Neem oil will keep some of the black spot and another fungus at bay.
The lawn will need sufficient watering to refrain it from yellowing and to keep the chinch bug at bay. That means that ideally, the soil should be moist to a depth of around 7 inches, but let it dry out before the next irrigation. It is high season for the chinch bug now which can kill big parts of your lawn rapidly. (Watch out for yellow straw-like spots that expand irregularly).
The vegetable garden is rapidly deteriorating in July. It’s too hot for the tomato plants to flower, the onions and the leeks are harvested. Even the french beans have given up. The okra and the sweet potatoes look unaffected by the hot weather, though. Give them at least 2 inches of water twice a week.