Read at : Google Alert – gardening
PORTLAND, Ore., Feb. 27 /PRNewswire/ — Jeff Gillman teaches horticulture at the University of Minnesota and has investigated the science behind many popular organic techniques. In The Truth About Organic Gardening (Timber Press) he confirms many long-held beliefs about organic benefits, while puncturing more than a few common myths.
True or false? Garlic not only repels vampires, it also repels whiteflies, aphids, and beetles.
A: True. Sprays made from garlic extract and water repel a variety of insect pests, as long as the spray reaches every part of the plant you want to protect.
True or false? Corn gluten meal suppresses weeds when applied to the soil.
A: True. If given enough time to work (usually a couple of years) and reapplied each year, corn gluten meal is a safe and effective pre-emergent herbicide.
True or false? Any mulch is good for soil and plants.
A: False. Some mulch, such as wood chips, can rob the soil of nitrogen, and is not always effective at suppressing weeds. Used incorrectly, mulches can damage plant stems through heat buildup, and can harbor insects and diseases.
True or false? Manure is always a desirable soil amendment.
A: False. Composted manure is a wonderful addition to the soil. Fresh manure shouldn’t be used because it can release ammonia, which can injure plants. Fresh animal manure can also contain weed seeds and human pathogens. E. coli can live in uncomposted manure for up to 21 months!
True or false? Japanese beetle traps are an effective pest control.
A: False. These traps generally attract more beetles than they trap.
True or false: Praying mantises are useful for controlling insect pests in the garden.
A: False. Mantises do not eat enough to effectively control harmful insects.
True or false? Rotenone, because it is organically derived, is a safe pesticide.
A: False. Rotenone is dangerous to beneficial insects and aquatic life, and is more toxic to humans than most other pesticides, organic or synthetic.
True or false? Compost and manure teas are great ways to provide nutrients and control diseases.
A: False. While these teas may provide small amounts of nutrients, they have the potential to spread nasty bacteria and their long-term benefits are unproven.
True or false? Insecticidal soaps are completely benign.
A: False. Although soaps are generally considered safe for humans, they can kill beneficial soft-bodied insects and damage certain plants if improperly used.
Gillman’s takeaway message? (continued)
The Truth About Organic Gardening
(Timber Press 2008, ISBN-13: 978-0-88192-862-4, $12.95).
SOURCE Timber Press, Inc.