Q. I have a problem growing spinach every spring. After I plant it in April, it grows for only four to six weeks before going to seed. Now I've received my first seed catalog of 1999, and notice that some spinach varieties are advertised as slow bolting. Do they work?
A. Yes, they'll give you an extended period of picking before they bolt - compared with other varieties of spinach.
Spinach plants send up seed stalks when plants are crowded, when day length exceeds 12 1/2 hours or when spring temperatures swing widely. You can extend your spinach harvest by planting as soon as the top inch of soil can be scratched in February or March, and by covering the plants with a floating row cover to shield them from excessive sun.
Q. Most of my azalea leaves either turned yellow or dropped off this past fall. They are old shrubs and this is the first time I've noticed it. What's going on?
A. Leaf yellowing and leaf drop are normal for azaleas. The severity depends a lot on the plant's location, the cultivar and, most important, stressful conditions during the growing season - for example, drought.
Stressed shrubs are more susceptible to serious disease and insect problems. Be sure to keep your plants watered during dry periods this spring.
Q. Several of my tree limbs are losing their bark. The bark is hanging in strips and the wood is completely exposed. I suspect energetic squirrels caused the damage. Will the branches die?
A. Most likely they will. Squirrels prefer to gnaw on small tree limbs, which usually cannot survive the damage. Squirrels are notorious for stripping bark. They use the bark as nest-building material and may also eat it. And like most rodents, they must gnaw on things to maintain proper tooth length.
This Week's Checklist
1. Keep compost bins covered to prevent leaching of nutrients from the compost.
2. Check your gardening tools. Plan to replace those that have worn out with high-quality, durable products.
3. Water houseplants when the top of the growing medium feels dry to the touch.
Garden tips are provided by the Home and Garden Information Center of the Cooperative Extension Service of the University of Maryland. For additional information on these questions, or if you have questions of your own, call the center's hot line at 800-342-2507, or visit its Web site at www.agnr.umd.edu/users/hgic.