AgroTips

Test for nematodes before planting vegetables.

Nematodes pose a major threat to nearly all vegetable crops in all soils. Unless you intend to apply a preplant fumigant, it is a good idea to collect soil samples for nematode assay before seedlings are planted and mulched. Any steps to prevent nematode problems must be taken long before the crop is established. For information on collecting and submitting samples for nematode assay, visit www.ncagr.gov/agronomi/uymem.htm.

Chemicals are not available for managing nematodes in home gardens.

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Now is the time to collect tissue samples from wheat.

Depending on where you live, you may need to sample now (eastern counties) or wait until late March (western counties). The best time to take tissue samples is when the wheat is at Zadoks Growth Stage 30 or Feekes Stage 4–5. At these growth stages, stems are upright and tillering has stopped. To collect a sample, break wheat plants off about 1/2 inch above the ground. Each sample should consist of about two handfuls of wheat — a composite gathered from 10 to 20 areas throughout the field. A pictorial guide to tissue sampling is available online at www.ncagr.gov/agronomi/pictorial.htm. Be sure to read the new wheat sampling and fertilization guidelines from NCSU.

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When growing peanuts, use agronomic tests to monitor zinc levels in the soil.

Growers who value the prime farmland where peanuts are produced should consider using alternate sites for waste application. Peanuts are very sensitive to certain metals found in waste, particularly zinc. Soils with NCDA&CS zinc index (Zn-I) values as low as 300 can be toxic to peanuts, even though other crops can tolerate levels up to Zn-I=2000.

In some areas, soil test data for peanut land already appear to show increases in zinc levels, indicating that waste is being applied to these fields. It is important to maintain a pH of 6.0–6.5 on sites where waste is applied. Low soil pH increases the availability and toxicity of metals.

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Apply lime now if recommended by your soil report.

By now, you should have already submitted soil samples and received your report. If lime is recommended, go ahead and apply it as soon as possible. For lawns, you may want to aerate the ground before application to maximize the ability of the lime to move into the soil profile. Liming soils to the target pH of the intended crop increases availability of plant nutrients already in the soil and supplies additional calcium and/or magnesium. Since liming can take up to 6 months to adjust pH, it is important to apply lime as far in advance of planting as possible.