It would appear that the calendar is running out of days in July. August always brings a new round of things to do in the yard. Let me tell you about a few things you should be doing.
When the weather gets hot, spider mites will attack many of your plants. Spider mites are a tiny insect. Unless there are a substantial number of them on your plant, you may never see them. They do create a series of tiny webs that allow them to move from leaf to leaf. Hence their name of spider mite.
These mites will suck the juice out of individual cells in a leaf. This feeding action kills the cell and eventually causes the leaf to develop a gray appearance. If you spot the tiny webbing on a leaf or if you see the gray appearance to the leaves on your plant, it is time to take immediate action.
If you wait to treat for spider mites, the numbers of this mite can reach thousands or more on a plant in a few short weeks. If you do not try to control this mite, they can eventually kill the plant.
If you are a vegetable gardener, you will find that they attack most plants that you are growing. I have seen them on plants in the squash family, tomato plants and beans. Many people will try to wash them off the plant with a stream of water. My experience has been that, yes, you will knock some of them off the plant, but the mites will rebound in a few days.
If you wish to use an organic approach, you can spray with pyrethrum. This spray is a quick-knockdown type of spray. Its advantage is that it is a short-lived spray. On most vegetable plants, you can spray today and harvest tomorrow. Its disadvantage is that it is a short-lived spray. If you have a heavy infestation, you will need to spray every two or three days.
You can also use an insecticide called neem oil. This comes as either a ready-to-use spray or a concentrate that you mix with water. It is very effective at killing spider mites. It is best to apply this late in the day or early in the morning. The reason for this is that the oil needs to dry before the plant is exposed to the sun. The oil can act like a magnifying glass and burn the leaves. Neem lasts longer on the plant, so you will not need to apply it as often and one application will kill many of the mites. When using neem, just a few applications spread out over a few weeks can control the mites.
Please keep in mind that even though the pyrethrum and neem sprays are organic, they are toxic to bees. Please apply these sprays when bees are not present and allow the spray to dry before the bees may show up.
There are many other synthetic sprays that you can use on your plants that are systemic in the way that they work. The spray is absorbed into the leaf and makes the juice of the plant poisonous. The systemics are long-lived in the plant, so you will have to apply less often for complete control of the mites. Systemic insecticides can be very poisonous to bees, so you will need to be very cautious when using them, and they are not usually recommended for use on vegetables.
Many cities and towns have instituted watering restrictions for outdoor watering. If you can water your plants, you should do the watering in the early morning hours. Plants absorb and hold water better if they are watered then. In some cases, you can water in the evening hours, but if the leaves of the plant stay wet in the nighttime, you will be encouraging the growth of fungus diseases.
If you have a total ban on outside watering, you can use what is known as gray water. This would be the water that you use in the house that goes down the drain. If you hand-wash dishes, save the rinse water to water your plants. If you take a shower, cover up the drain and collect the water to water your garden. If you have a rain barrel, you can use that water to water your plants.
Well, that’s all for this week. I’ll talk to you again next week.
Tim Lamprey has worked in the lawn and garden industry for 45 years.