TIMOTHY DALY: Separating gardening myths from facts

Myth: “Organic pesticides are natural products toxic to pests but harmless to other living things.”

Fact: We wish this were true. Many organic pesticides are safer, but some can be quite poisonous. Rotenone is made from the roots of derris plants and is toxic if swallowed or inhaled and harmful to fish. An old-fashioned (hopefully obsolete) organic pesticide, nicotine sulfate, is more toxic than the synthetic insecticides Malathion and Sevin. Select pesticides carefully, whether they are organic or not. Use them only when necessary and follow all label directions.

Myth: “The soil under pines and oaks is acidic.”

Fact: The soil’s acidity depends upon the rocks beneath it, not the trees above it. Test your soil to see if your soil needs liming and how much to apply. Soil test through UGA Extension Gwinnett now, apply lime and fertilize using this information. Please contact the Extension office for instructions on testing your soil.

Myth: “Mushrooms growing in a lawn means the soil is deficient.”

Fact: Actually, these are the fruiting structures of fungi growing under the ground. Some fungi rot wood or other organic matter on or under the soil. Others live in harmony with tree roots, which help them take up water and nutrients — a few cause plant diseases. The sudden appearance of mushrooms does not mean the lawn needs fertilizer. They have no control except to rake them up or remove the decaying organic matter.

Myth: “Moss growing in a lawn means it needs lime.”

Fact: Though acidic soil favors moss, other causes promote its growth. Shady areas, especially with bermudagrass lawns, poor drainage, and compacted are conducive to moss.

Many more myths exist, and I find it surprising how many people believe them accurate. The best source of information available is from Extension and University websites that usually end with .edu. The information is research-based and is non-biased. The type found in many companies that sell horticultural products may be inaccurate. There is a bias toward the company’s products; they are trying to sell you them.