Aphids

Also known as: Plant lice, greenfly, blackfly

Identification

Tiny soft-bodied insects (1-3mm), pear-shaped, found in clusters on new growth and leaf undersides. Colors: green, black, red, yellow, or white depending on species. May have wings or be wingless.

Damage

Sucking — pierce phloem vessels, cause leaf curl, transmit viruses, excrete honeydew attracting sooty mold

Best Organic Solutions (Ranked)

Solutions ranked by reliability tier — start with Tier A options.

Insecticidal Soap Tier A

Best first response — safe, effective, no residual

Neem Oil Tier A

IGR action prevents reproduction

Horticultural Oil Tier A

Suffocates on contact

Pyrethrin Tier A

Fast knockdown for severe outbreaks

Beauveria bassiana Tier B

Long-term biological suppression in humid conditions

Biological Controls

Ladybugs (larvae eat 200-300 aphids before pupating), green lacewing larvae, parasitic wasps (Aphidius colemani), hoverfly larvae

Prevention

Avoid excess nitrogen fertilization (promotes succulent growth aphids prefer). Encourage beneficial insect habitat. Row covers on vulnerable transplants. Inspect new plants before introducing to garden.

Common Mistake

Spraying broad-spectrum insecticides that kill predators, causing worse aphid rebounds. Aphid populations crash naturally when predators arrive — wait 7-10 days before treating light infestations.