When I brought my Thanksgiving cacti indoors, they produced many flowers, but one plant dropped buds. Pesticide didn't help. What's the problem?
Bud and leaf fall in Thanksgiving cacti can be caused by too little water, too much water, excessive nitrogen, deficient potassium, rapid changes in temperature and drafts. Excess buds or flowers may drop naturally. Rotating a plant when buds are small may also cause sudden bud fall, possibly because buds turn to face the light and the effort weakens them. Try not to change the plant's position relative to its light source while in bud. Always identify a pest before using pesticides.
I'm starting a vegetable garden next spring. How do I amend the soil? I can get free horse manure. Can I put it down this fall in preparation for spring planting?
All organic amendments (with the exception of peat moss) would be good for your vegetable garden. Horse manure is often full of weed seeds even when composted, though you can't beat the price. Work in a thick layer of your organic amendments -- 4 or more inches -- especially if topsoil is thin, infertile or compacted. Get a soil test done soon. Lime is generally needed in Maryland's acidic soils. Lime takes a long time to raise pH, so adding lime now ensures the right pH by next spring.
Shred fallen leaves with a lawn mower. Mulched leaves up to 1 inch in depth may decompose in place. Deep piles smother and kill turf.
Spray scale insects on trees and shrubs with horticultural oil after leaves drop. Remember that temperatures must remain above freezing for 24 hours after spraying oil.
Ellen Nibali, horticulture consultant, works at Maryland Cooperative Extension's Home and Garden Information Center, and David Clement is the regional specialist. The center offers Maryland residents free gardening information. Call the center's "hotline" at 800-342-2507 (8 a.m.-1 p.m. Monday-Friday) or e-mail plant and pest questions through the Send a Question feature at hgic.umd.edu.