University of Vermont Extension 
Department of Plant and Soil Science

Summer News Article


Dr. Leonard Perry, Extension Professor
University of Vermont

Three questions many ask us in Extension this month include how to keep deer out of gardens and landscapes, what is wrong with your tomatoes, and is it too late to start annuals to fill in gaps in the garden?

If there aren't many deer, or they aren't very hungry (other sources of food nearby such as in woodlands), repellents may work.  Try hanging human hair or strong-smelling soap in bags around the garden as odor repellents.  Pepper sprays are a popular taste repellent if only a few desirable plants need treating.

Motion security lights (I have a solar powered one mounted on a portable stand) and radios can also keep deer away.  Just make sure you move them around every few days.  Deer are smart, and once they learn these are fixed and not of harm, these devices are no longer effective.

Planting types of plants deer don't like to eat may also work, but if they are really hungry, they may eat most any plants.  Excluding deer with fences is more costly, but more effective.  Either use high fences (eight feet or more), or electric fencing.  Some people use one strand of low-voltage electric wire, baited with peanut butter.  One taste tends to discourage deer from returning.  Gardeners have designed other creative arrangements of low-voltage electric wire; check gardening books and Web sites for ideas.

Another question we often get is, what are the large, dry, dark brown sunken areas at the blossom end (bottom) of the fruit?  Margaret Hagen, from the University of New Hampshire Cooperative Extension, says that this is blossom-end rot, a common disorder of tomatoes.

This problem is caused by a lack of calcium in the developing fruits.  Its occurrence depends on conditions that affect the uptake of water and of calcium in developing fruits. Roots failing to get enough water and calcium for the fruits often causes this problem.

Blossom-end rot may occur when rapidly growing plants are suddenly exposed to drought. Or if roots are damaged, from disease or too close cultivation, the problem can occur.  Cold, heavy soils that result in poor root systems also cause this problem.  Prevent any of these situations, and you'll hopefully prevent this disease.

It may be too late to start annual flowers, says Dr. Lois Berg Stack from the University of Maine Cooperative Extension.  This is mainly because flower seeds may be hard to come by, unless you have some left.  Fortunately, many complete garden stores now offer high-quality annuals through most of the summer, and most are in larger pots for a more instant effect.

If you do have seeds, sow those that develop quickly right into the garden.  These include such as pot marigold, zinnia, and moss rose.  Other annuals tolerate light frosts, so bloom well in early fall if sown now.  These include such as sweet alyssum, cornflower, and Shirley poppy.  Some vegetables also grow well into fall, and are quite attractive in gardens as well as for eating.  These include colored lettuces, flower kale, flowering cabbage, and chard.

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