Pests & diseases › Colorado Potato Beetle
Colorado Potato Beetle
Yellow beetle with 10 black stripes on wing cases. Devours potato, eggplant, tomato foliage. Found in nearly every state.
Symptoms
- Adults: 10mm yellow beetle with five black stripes on each wing case
- Larvae: bright orange-red humped grubs feeding in clusters
- Foliage stripped from plants
- Both adults and larvae feed continuously
Lifecycle
Adults overwinter in soil. Two generations per year in most regions.
What to do
- Hand pick adults, larvae and bright orange egg clusters from leaf undersides — drop in soapy water
- Bt san diego strain (specific to potato beetle larvae)
- Spinosad on young larvae
- Neem oil deters egg-laying
If it's bad
- Pyrethrin
- (Many populations resistant to multiple chemicals — rotate active ingredients)
Stop it coming back
- Three-year rotation away from potato/eggplant/tomato
- Mulch with straw (slows adult movement to plants)
- Resistant potato varieties: King Harry
Crops it goes for
Plan the plot, track every sowing, cook the harvest
Sowing reminders and harvest forecasts for your own frost dates, the Seed Tin, Scan Centre for any label or packet, and the Potty Mouth Garden Club. Free to start.