Ask the gardeners

We have a beautiful sweet cherry tree (Oxheart type) that blooms profusely every year, but we never get any cherries. Why?

All sweet cherry trees need another variety for cross-pollination, so that pollen from one tree will fertilize the blooms of the other. The recommendation is to plant both a light variety and a dark variety.

Schmidt's Bigarreay, Black Tartarian, and Hedelfingen are good pollinators for yellow or gold varieties, such as Napoleon (Royal Ann) and Emperor Francis. Sour varieties are self-fruitful and somewhat hardier. They also bloom later than sweets, thus usually missing late-spring frosts.

Popular varieties are North Star, English Morello, and Montmorency, which has long been the leading sour variety used for pies, conserves, and desserts.

For quite a few years I have planted tomatoes. They always grow well, but when they start to ripen, they develop spots which spread on the fruit. What can I do to prevent this condition?

One of two problems is quite involved. Anthracnose causes small, round, sunken, watersoaked spots when fruits become fully ripe. It is worse on infertile and poorly drained soils.

Make sure you have well-drained soil, fortified with plenty of organic matter (compost and/or rotted manure). Also, the fruit should be picked as soon as it turns ripe - and kept picked. If you notice any signs of the difficulty you can spray with Zineb or Maneb, according to directions.

Another problem might be botrytis fruit rot, which can be brought on by damp, cloudy weather and poor air circulation.

Both anthracnose and botrytis troubles can be minimized by growing tomato vines on a fence or wire corset.

Recently I have seen impatiens that look like globes, being very round and compact, in hanging containers. How can I make similar containers?

First of all, the impatiens plants (patient lucy) were started 11 or 12 weeks before they were offered for sale in the containers.

For a globelike effect they are either transplanted into hanging baskets that have holes in the sides or put in wire containers which contain moist sphagnum peat moss so that they grow out of spaces other than just the top.

Also, to keep the growing tips even with one another, they are pinched back when they reach out too far. These snips can be rooted in water if two inches long or so.

If you start seeds now, you'll have hanging baskets for fall and winter. If you live in a cold part of the country, grow them indoors in a good light window. Impatiens will tolerate a temperature of 45 degrees F. and still grow well.

My most frustrating problem is to find information about soil requirements (acidity, alkalinity) for various plants. I want to mix flowers and vegetables in one area. Is there a good source of information consolidated in one book?

Most state colleges have this information free for the asking. Or you can write to Sudbury Laboratory, Inc., Sudbury, Mass. 01776. They have a fine booklet which lists pH (acidity) preferences for flowers, houseplants, ornamentals, fruits, and vegetables. They also manufacture simple soil test kits.