Overgrown Jade Plant Can Be Pruned

Q:I have a 30-year-old jade plant that has outgrown my living room and its pot. I'd like to prune it, but don't know how or when. I'd also like to repot it, but it's very heavy and may break apart. What should I do?

A: It probably would be prudent to leave it in its current pot and perhaps prune it a bit to reduce the size of the top. Jade plants can be pruned just like any shrub. Simply cut each branch or stem back to a lateral growing in the direction you want. If you wish, you can cut back to any leaf from which node growth will then proceed. It may be best to do this just before growth starts in earnest in spring. New growth will cover the pruned stems.

If you repot your jade plant in new soil, it will just tend to get bigger. A jade plant can grow indefinitely in a container, although as it fills its pot with more and more root system, it may need watering more frequently during the season of active growth (usually spring and summer). However, since jade plants are exceedingly drought-tolerant, this should not be much of a burden. In fact, during the normal winter dormant period, jades should not be watered at all and should be kept cool, if possible. This will enforce dormancy, slow growth and may even lead to flowers in spring.

Q: Do fruit flies that infest house plants produce white larvae?

A: Fruit flies do not infest house plants. The small insects often seen hanging about potted plants are fungus gnats whose small, white larvae (maggots) infest the soil. They feed on decaying organic matter and roots. Large numbers of them in a pot may damage enough roots to cause serious stress for a plant. Control is directed at the flying adults with the use of yellow sticky traps. Stick them in the soil or hang in the vicinity of the plants to attract the adults. Gnatrol is an insecticide used by commercial growers, but it may be difficult to find in retail stores.

Q: I have a blue spruce in my yard, but some disease has been killing it. There are hardly any needles on it, and it looks awful. What can I treat the tree with to make it healthy?

A: Colorado spruces and virtually all North American species of spruce are very susceptible to attack by the spruce aphid here in Western Washington. This is a very small (even by aphid standards) green aphid that sucks the previous season's needles dry during the winter/early spring. When warm weather arrives in May or later, these needles fall off the tree, leaving the plant with only the current season's foliage out at the branch tips. The interior of the tree tends toward hollowness instead of the thickly foliaged, well-clothed appearance it should have.

Check several times during the winter and early spring to see if an infestation exists. Look carefully (a magnifying glass helps) at last season's needles. Lots of very small, green aphids should be a signal to act. Insecticidal soap should give good results, but thorough coverage is a must. Or spray the tree with an insecticide labeled for controlling this minimonster on spruces.

Spruce spider mite is another microbeast that can cause spruces to look very bad. Mites do their dirty work during hot, dry summer periods like we've had this season. Act quickly if the needle become tan or bronzy and fall off. Fine webbing often will be obvious along the branches. Use the soap or an insecticide labeled for use.

Spruce aphids do not seem to be a problem in colder winter areas of the state. However, fellow gardeners in Eastern Washington should be vigilant for spider mites.

Worth noting

-- Rare Plant Nursery Tour - Heronswood Gardens & Nursery and the owner's show gardens will be open for tour from 10 a.m. to 4 p.m., today and Saturday. Specialists in rare and unusual shrubs, trees, vines, grasses. Nursery is 1 mile north of Country Corner at 7530 288th St. N.E., Kingston, Kitsap County.

Gardening runs Friday in the Scene section and Sunday in Home/Real Estate of The Seattle Times. It is prepared by George Pinyuh and Holly Kennell, Washington State University/King County Cooperative Extension agents; Mary Robson, Master Gardener program assistant and volunteer Master Gardeners. Send questions to: Gardening, The Seattle Times, PO Box 70, Seattle, WA 98111. Questions of general interest will be answered as space allows.