pest control

Cause

Bacillus thuringiensis (Bt) is a soil-dwelling bacterium that produces crystalline insecticidal proteins; caterpillars ingest Bt spores, which disrupt gut lining leading to starvation and death within 24-72 hours

Solutions

• 1. Identify caterpillar pest — Bt kurstaki (BTK) targets lepidopteran larvae (caterpillars); apply at first sign of feeding damage
• 2. Mix BTK according to label directions; use within 24 hours of mixing for maximum potency
• 3. Spray leaf surfaces thoroughly, especially undersides where caterpillars feed; BTK must be ingested to be effective
• 4. Apply during calm evening conditions to maximize leaf retention and minimize UV degradation
• 5. Reapply every 5-7 days during active feeding or after heavy rain; BTK is contact-killed by rainfall

Cause

Beneficial insects (lady beetles, lacewings, predatory mites) are predators and parasites of plant pests, naturally suppressing aphid, mite, and caterpillar populations in gardens

Solutions

• 1. Identify the pest problem first — different beneficials target different pests (ladybugs for aphids, lacewings for caterpillars, predatory mites for spider mites)
• 2. Purchase beneficial insects from reputable suppliers and release in late afternoon near heavily infested plants
• 3. Release at recommended rates: 1,000 predatory mites per 200-500 sq ft; 1 ladybug per 100 aphids estimated; 500 lacewing eggs per 100 sq ft
• 4. Provide moisture and shade near release sites; avoid releasing near ants which farm aphids
• 5. Make repeat releases annually for non-native species that cannot overwinter in your climate zone

Cause

Diatomaceous earth (DE) is composed of fossilized diatom remains with microscopic sharp edges that penetrate insect exoskeletons, causing fatal water loss through desiccation

Solutions

• 1. Use food-grade diatomaceous earth only — pool-filter DE contains harmful additives; look for 85-95% silicon dioxide content
• 2. Dust lightly on dry soil around plant stems and along garden bed edges; apply during calm, dry conditions
• 3. Lightly dust plant surfaces where soft-bodied pests (aphids, thrips, leafhoppers, caterpillars) are present
• 4. Avoid heavy applications that can harm beneficial insects and bees; DE is non-selective and kills all insects it contacts
• 5. Reapply after rain or overhead watering since moisture reduces DE effectiveness; best used in arid conditions

Cause

Insecticidal soap disrupts cell membranes of soft-bodied insects on contact, causing rapid dehydration and death within minutes to hours

Solutions

• 1. Apply insecticidal soap spray directly on soft-bodied pests (aphids, mealybugs, spider mites, whiteflies, scale crawlers)
• 2. Spray plant surfaces thoroughly, especially leaf undersides where pests congregate, until wet but not dripping
• 3. Make fresh application every 3-4 days to catch newly hatched nymphs; soap only kills what it contacts
• 4. Avoid spraying in direct sun or when temperatures exceed 90°F to prevent leaf burn
• 5. Test on a small area first on sensitive plants; rinse after 30 minutes if no damage

Cause

Neem oil contains azadirachtin, which disrupts insect feeding, molting, and reproduction by interfering with hormonal balance

Solutions

• 1. Mix 0.5-1 teaspoon neem oil concentrate per quart of warm water with 1/4 teaspoon liquid dish soap as emulsifier
• 2. Shake vigorously before each application to ensure even distribution
• 3. Spray undersides of leaves thoroughly — insects hide there; cover all plant surfaces until just before runoff
• 4. Apply in early morning or evening to avoid leaf burn and maximize contact time with pests
• 5. Repeat every 5-7 days for active infestations, every 14 days for prevention