I put our fall leaves and kitchen scraps in a pile to make compost. A neighbor gave me rabbit manure for the pile, too. How do I know when compost is ready to use in my gardens?
This is critical when manures are used, because uncomposted manures can burn plant roots and stems. Fortunately, it's easy to tell when the ingredients are composted. Pick up a handful of your aged compost. Crumble it. It should look like dark, rich soil, consistent in texture. The original materials will be unrecognizable, except perhaps tiny twig or wood bits. Finally, smell the compost. It should have a pleasant earthy fragrance. Enjoy.
I've had lavender plants for a few years. New growth overruns some old growth. Should this plant be cut back?
Each spring, prune when new growth emerges from old stems. Prune off no more than 1/3 of the plant at a time. Flower stalks can be cut back to their base, but don't cut into the woody parts. Do not cut it down to the ground, as lavender are actually subshrubs, not perennial flowers, although we use them as such. They tolerate shearing well.
Every two or three years, when they get straggly, do a renewal pruning. Prune back to 6 to 8 inches or half its height in early spring after new growth has appeared but, again, not so far that you cut into old wood, which cannot rejuvenate.
Repot and divide houseplants that are outgrowing their containers. Be sure to scrub out fertilizer salt residues on containers before repotting.
Avoid the temptation to fertilize ornamental garden plants that appear to be healthy and productive. Overfertilization, especially too much nitrogen, can lead to overly succulent, weak growth and encourages sucking insect pests like scales and aphids.
Ellen Nibali, a horticulture consultant, works at Maryland Cooperative Extension's Home and Garden Information Center, and Jon Traunfeld is the director of the Home and Garden Information Center. The center offers Maryland residents free gardening information. Call the center's help line at 800-342-2507 or e-mail plant and pest questions through the Send a Question feature at hgic.umd.edu.