Q In my travels through the Eastern states, I have seen beautiful plantings of crown vetch along the highways. I would like to establish this on my own property in northern Wisconsin, but I have concerns about its wintering well. If it would be a suitable ground cover here, could it be grown from seeds, or would I need started plants? W.S.W. Green Bay, Wis. Crown vetch (Coronilla varia), with its fine leaved foliage and pink florets in a crown-shaped circle, is suitable for large areas. Its sprawling, two-foot-high growth and aggressive underground roots make it undesirable for small properties. It is excellent for holding soil on slopes. Being a legume, it adds nitrogen to the soil.
Started plants can be set about 12 inches apart, or seeds can be broadcast on loose soil. When purchasing seeds, ask for an inoculant of nitrogen-fixing bacteria to mix with the seeds.
On slopes, a landscape mesh or loose mulch keeps seeds from washing away. Frequent watering hastens germination, but once established, crown vetch is very tolerant of dry soil.
It will not tolerate ``wet feet,'' and it does not do well in climates of prolonged hot weather. It can thrive where temperature may drop to minus 40 degrees F. if it has snow cover. Be aware that it turns brown in fall, then comes up again from the roots in spring. Pengift is a good, readily available variety. Q I have always been fond of red Delicious apples. I have just been told that those pronounced knobs on the calyx end of the apple are induced to grow there by spraying the apples with a substance known as Promalin. I hope you will tell me this is not true. C.B. New York
In most areas of the Northwest and Midwest, United States red Delicious apples form the protuberances on the calyx end naturally. Some other parts of the country, which do not have the identical growing conditions, use the chemical Promalin to induce these apples to more resemble the shape by which people most identify that particular variety. It causes the apple to ``stretch'' and assume a more conical shape, with bumps on the end.
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