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The Spokesman-Review Newspaper
Spokane, Washington  Est. May 19, 1883

Moisture, pests most common tomato issues

Gary and Carol Polser The Spokesman-Review

Many gardeners get frustrated when their tomatoes appear to be failing or just don’t look good.

Early blight is a fungal disease characterized by dark brown, irregular spots, with yellow halos developing on the fruit. Control it by improving air circulation and avoid wetting the leaves.

Blossom-end rot is caused by a calcium deficiency in developing fruit. It is characterized by dark brown, leathery spots on the blossom end of the fruit. You can apply calcium during soil preparation and use calcium foliar sprays.

Overwatering can cause the leaves to roll upward, feel leathery, but remain green. Plants are not stunted. Tomatoes need even moisture to produce good fruit, so try to keep the soil constantly damp, but not too wet. Water deeply, and then check daily to ensure the soil hasn’t dried out too much. Tomatoes in pots will need more frequent watering, perhaps even daily if they are in full sun for the entire day.

If your young plants get cut off at the ground you should suspect the infamous cutworm. You can use cutworm collars or biological control agents. The collars can be made of any material that can be formed into a 4-inch tall ring and placed around the base of the plant.

In the garden this week

•Keep up with the weeding and consider adding a light summer mulch like bark or pine needles if your soil dries out quickly, especially around vegetables.

•Deadhead annuals and perennials to keep them blooming. Perennials that have finished blooming can be cut back, but wait until cooler weather before digging up and dividing.

•Vegetables will be ripening rapidly, so keep them harvested regularly to avoid spoilage and encourage additional production. If they develop leaf spots (either brown spots or blotches that may be ringed in yellow), pull them out and destroy them before the disease spreads.

•Frequent cuttings from herb plants encourage new growth, so cut and dry herbs regularly.

•Don’t fertilize woody perennials, shrubs and trees after the beginning of August – this will allow them to begin the hardening-off process in preparation for winter.

•Yellow jacket season will be in full swing for the next few weeks, so be prepared with wasp and yellow-jacket sprays. But remember, even though they’re pesky, they are also good for your garden. If they aren’t bothering you, don’t bother them.

•Evergreens, leafy shrubs and hedges are subject to mites, which are hot weather critters that live on the undersides of leaves. They suck plant sap and cause the leaves to yellow. The best control method is simply to wash the plants down with a hose now and then.