Planning now for next summer's tomatoes; aromatic wild leeks

Q It is good to see the seed catalogs coming in. Would you please clarify a point for us? When the number of days is given for fruiting of tomatoes, does it mean the number of days after they are set into the garden or the number of days after the seeds are sown indoors?

Unless otherwise specified, it means the number of days after the transplants are set out in the garden. We usually start seeds indoors six weeks before we plan to set plants outdoors.

If you wish to start seeds earlier, you can continue transplanting into pots of larger size and then move the plants outdoors when they are almost ready to produce. However, you need a greenhouse or a good light area to do this, or the plants will get very spindly and produce poorly.

You also need to take care in transplanting unless you plan to keep them in a container.

Q When I was a youngster attending a rural school, we used to go to the edge of a wooded area in the spring and pull up the most delectable leeks and eat them during recess, much to the teacher's dismay. We did not think the ''aroma'' that bad; in fact, my grandmother made a wonderful leek-and-potato soup from them. Is it possible to get the slim, broad-leaved type of leek? I've tried many tame varieties, but they get thick-stemmed and do not have quite the same flavor.

We are very familiar with the wild leeks as well: slim, with broad leaves, growing a bit less than a foot tall. They are native to an area encompassing southeastern Canada, the eastern United States as far south as Georgia, and as far west as Minnesota.

The wild leeks thrive in rich, woodsy earth and, unlike tame leeks, tolerate dappled shade. Since you live within the area described above, you can probably find a friend or acquaintance who has some growing on his property.

A friend invited us to dig some, which are now thriving near our woods and used generously each spring in a number of delicious recipes.

Q In an attractive fireplace arrangement, I saw brown-toned, although fresh-looking, rhododendron leaves. I was told they turn that way when glycerin is added to the water. I have already wasted one bottle of glycerin with no results. Why isn't it working for me?

Almost all kinds of foliage can be treated with glycerin, and they will last indefinitely. Single leaves or short stems of leaves can be laid directly in the solution. Longer stems should be pounded on the ends and stood upright with 4 inches of the stems in the solution, consisting of 1 part glycerin to 2 parts water.

Freshly picked foliage should be used, and the solution should be no cooler than the normal room temperature. All will turn a darker color but will have an attractive sheen and can be used with either fresh or preserved flowers, grasses , pods, or fruit.

The foliage should be removed from the solution after it has noticeably changed color. The solution can be used many times.

Q I would like to know how to care for a delicate pink Christmas cactus now that it has finished blooming. It is the first one I've ever had, and I'm confused because a friend tells me to water it only half as much, while another says I must keep on watering it the same amount. What do you say?

Continue to water it the same as you did when it was blooming, since it will be putting out green growth. Also give it some liquid plant food about once a month, following the directions on the package.

Keep it out of direct sun. In the summer, set it outdoors in a shady spot or in the coolest room you can find.

In early September stop feeding the cactus and water it only enough to keep the stems and leaves from shriveling. Also at this time, and for the next 8 weeks, the plant should be kept at night in a spot where the temperature is 50 to 55 degrees F. If you cannot provide this temperature, see that the plants get 13 hours of darkness every night until early November.

Cool night temperature or light control is important for bud formation.