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Pests in Gardens and Landscapes: Quick Tips

Roots on plants at right have been damaged by damping off pathogens.

Seedling at left has been killed by damping off.

When seedlings die soon after germinating, the cause is often one of several pathogens that lead to damping-off disease. Seeds may rot before they germinate, shoots may decay before they appear or stems of seedlings may rot at the soil line. Damping-off is most common when soil is compacted and conditions are wet and cool. To manage damping-off, plant at the right time, germinate seeds indoors in disease-free soils, and follow planting practices that reduce disease risk.

Plant in warm, moist soils with good drainage.

• Don't plant seeds or transplants into cold, wet, compacted soil.
• Wait for the outdoor soil and air temperatures to warm up.
• If starting seeds indoors, keep in a warm area or use heat mats under seedlings.
• Shallow planting will speed up germination outdoors if conditions are marginal.

Improve drainage in compacted, waterlogged soils.

• Use raised planting beds.
• Add soil amendments such as redwood shavings, peat moss, or bark.
• Use potting soil for indoor seeding of transplants.
• Avoid using unfinished or green compost, which holds water and promotes disease development.
• Mist seedlings instead of soaking the soil.

Use good cultural practices for seedling plants.

• Don't overwater.
• Thin plants after they emerge to improve air circulation.
• Don't overfertilize with nitrogen.
• Rotate crops to avoid planting the same crops in the same place year after year.

Employ good sanitation practices.

• Use clean, disease-free pots and soil.
• Remove and discard diseased plants.
• For plants grown in pots or cold frames, use steam-treated soil or pasteurized potting mix.
• Outdoors, consider solarizing soil before planting, a method that uses the sun’s heat and clear plastic to kill soil-borne pests.
• Use the highest quality seed available.

Minimize the use of pesticides that pollute our waterways. Use nonchemical alternatives or less toxic pesticide products whenever possible. Read product labels carefully and follow instructions on proper use, storage, and disposal.