Q. I was given some full-grown foliage houseplants by a neighbor who is leaving the area. They're beautiful, but I know nothing about houseplants. Right now I'm worried that they're overgrowing their pots. How do you know when to repot? What should I do if it's time?
A. When the roots grow out of the bottom of the pot, it's time to repot. Select a new container (with drainage holes). It should be 1 to 2 inches greater in diameter than the old pot.
Buy a nonsoil growing medium - a mixture of peat, vermiculite and perlite. Moisten the medium and place a few inches in the bottom of the container. Gently remove your plant, prune back long and dead-looking roots and repot into the new container. Fill the pot to within 1 inch of the top with the medium but don't press down.
Water your plants only when the top of the medium dries out. Locate your adopted plants where they will get the same light exposure/intensity they received at your neighbor's.
Q. I've noticed some strange growths that resemble little pineapples on the twigs of my Norway spruce. It's a young tree, so they couldn't be cones. Is it a fungus?
A. No, it's Eastern spruce gall, a fairly common and not very serious pest. The galls are caused by adelgids - insects that resemble aphids. Apply a dormant oil spray now to kill over-wintering nymphs. In spring or early summer, prune out the galls.
Q. I read that you could control a lot of vegetable insect pests by tilling the soil in the off-season. Is this worth it?
A. The idea is that tilling will disrupt the habitat of over-wintering pests. Some pests are destroyed during the tilling; others are exposed to the elements and to predators. Tilling can be helpful, but keep in mind that not all insect pests over-winter in the garden. For example, the Colorado potato beetle, cucumber beetle and Mexican bean beetle also over-winter in protected areas adjacent to vegetable gardens, and corn earworm and fall army worm will fly in next summer to feast on your plants. Furthermore, tilling may lead to soil erosion. You'll have to balance these factors before making a decision.
This Week's Checklist
1. If you'd like to become a "Maryland master gardener" next spring, call 800-342-2507 now for information on training dates and fees.
2. Clean and sand the rust off garden tools; rub linseed oil into wooden handles; sharpen edge tools.
Pub Date: 12/06/98