Ask the gardeners

Twice in June I tried to plant green beans but got no plants. After digging up each planting I found some rotting seeds and many remnants of small sprouts, but none pushed above the ground. What happened?

In your part of the country, June was an unusually cold, wet month. Beans do not germinate and grow well when night temperatures are in the low 40s and daytime temperatures are below 60 degrees F.

This, along with the moisture, rotted the seeds, either right after they germinated or before they had a chance to sprout.

Please tell me what would cause the fruit on my young apricot tree to fall off. They look as though they have little holes in them, but I can't find any worms or bugs inside.

The villain is the humped-back curculio, which lays its eggs in crescent scars (usually one in each fruit). The crescent shape is to keep the egg from being crushed as the fruit grows.

The egg has probably hatched into a tiny worm which is starting to make its way into the fruit, thus causing a stress that makes the fruit drop off.

Be sure to gather up the fallen apricots and trash-bag them so the worms cannot pupate and carry on the cycle next year.

I have a small fig tree in a wooden tub and I've been told I can transplant it to the garden even though in our area it would not be hardy outdoors. Could you suggest how I might winterize it?

In locations where temperatures often fall below freezing, figs are handled three ways. Here they are:

* Leave them in large tubs and move to a cool, light place for the winter. We move ours to our garage, which never falls below 32 degrees F. We have the tub on a platform with casters. The longest branches are pruned back in the fall.

* You can leave the tree in the ground and wrap it in its upright position after cutting it back somewhat.

Friends of ours wrap the tree tightly with snow fence. They then tack heavy insulation to the snow fence while adding straw or leaves in between the branches, around the roots, and over the top.

Next comes a wrapping of canvas around and over the bush, followed by a wrapping of tar paper over the canvas. After all danger of frost has passed in the spring, the tree is carefully unwrapped.

* Branches are tied together and the roots on one side are separated from the soil. This allows the tree to be tipped over on its side into a trench which has been dug to accommodate its height and width. Some branches have been tied back.

It can be tied down with tent stakes or weighed down with a couple of large flat rocks. Then it can be covered with leaves, straw, hay, etc., and, finally, mounded with a foot or more of soil. Canvas or tar paper is usually put over it all. Then in the spring the tree is uncovered and pushed back to its normal position, the trench filled in, and the roots firmed into the soil.

Recently you mentioned a sweet cherry which didn't produce fruit because of a lack of cross-pollination from another variety. There is a remedy for this which does not necessitate planting a new tree. Other varieties could be grafted onto the branches of the existing tree. I've successfully grafted several stone fruits on one tree.

Thanks to our reader for mentioning this. Other varieties could either be ''budded'' or ''grafted'' onto a tree. Budding refers to transferring a bud from one tree to another; grafting refers to cutting twigs from a tree and implanting them on another.

Buds and grafts must be done on varieties of the same species or closely related species of the same genus. In other words, a seed fruit could not be budded or grafted to a stone fruit.

It takes practice, that's all. Don't be discouraged by some failures. Our ''Green Thumb Garden Handbook'' and ''Green Thumb Book of Fruit and Vegetable Gardening'' both have directions (illustrated) for budding and grafting.

We would love to attract hummingbirds around our new home. Would you please name some flowers that are especially attractive to these little beauties?

Over the years we have noticed that hummingbirds seem to prefer red flowers, although they will go to others if the red flowers are not present.

They like tubular florets (tiny or medium) which include coralbell, columbine , phlox, and monarda in the perennial group. Monarda (beebalm or Oswego tea) is a favorite, and many nurseries offer ''hummingbird collections.''

Trumpet vine is sure to attract them. Annuals, such as impatiens, red salvia, petunias (red and pink), and bright gladiolus, are favored in our garden.

Hummingbirds seem to prefer miniature glads over the large ones.

If you have a question about your garden, inside or out, send it to the Gardening Page, The Christian Science Monitor, One Norway Street, Boston, Mass. 02115.