What's Eating Your Peach Tree?

Probe and dig out larvae each spring and fall

Permethrin trunk spray in late June and again in August

Spray permethrin (Bonide Borer-Miner Killer, ~$18) on the lower 18 inches of trunk and the surrounding soil. Time the first spray for late June when adult moths emerge, and a second spray 6 weeks later for the second flight. The barrier kills hatching larvae before they bore in. Skip if the tree is in flower or if you keep beekeepers nearby.

Pheromone mating disruption ties for orchard-scale prevention

Hang Isomate-P pheromone ties (~$30 for a pack that covers 4 trees) at chest height in May. The pheromone confuses male moths and prevents mating, so few eggs ever land on your trunks. Works best when neighbors are also treating, otherwise outside moths can still find your tree.

Prune wilted shoot tips weekly through May and June

Walk the tree every 7 days during spring shoot growth. Snip off any wilted, drooping shoot tips 4 to 6 inches below the dead wood. The larva is still inside the cut piece. Bag and trash the prunings. Do not compost. This breaks the first generation before larvae move to the fruit.

Spinosad spray on developing fruit, every 10 days

Hang pheromone traps in March to time sprays

Hang two oriental fruit moth pheromone traps (Scentry or Trece, ~$12 each) in the canopy by mid-March. Check weekly. The first big trap catch tells you the moth flight has started, so you can time spinosad sprays 7 to 10 days later when eggs hatch. Replace lures every 6 to 8 weeks.

Tarp-and-jar shake every morning at petal fall for 3 weeks

Surround WP kaolin clay spray, weekly through June

Mix Surround WP kaolin clay (~$25 for 25 lb) at 1 cup per gallon and spray the entire tree to a white film starting at petal fall. The clay irritates the weevil and prevents egg-laying. Reapply weekly and after every rain through June. Wash fruit before eating, the clay is food-safe but unpleasant.

Pick up and bag every dropped fruit through June

Walk under the tree every 2 to 3 days from petal fall through late June. Bag every dropped fruit and trash it (do not compost). Most drops contain a live larva that would otherwise mature in the soil and emerge as next year's adult. Sanitation alone can cut next-year pressure in half.

Dormant oil spray in late winter, before bud swell

Summer oil targeted at the crawler hatch in late May

Wrap a piece of double-sided sticky tape around an infested branch in early May. When tiny yellow specks appear stuck to the tape, the crawlers are hatching. Spray summer-rate horticultural oil within 7 days, while crawlers are still mobile and unprotected. Repeat once 10 days later to catch stragglers.

Prune out the worst-encrusted branches in winter

Cut off any branch where bark is more than half covered in scale. Bag and trash the prunings. Removing the heaviest reservoirs gives the rest of the tree a fighting chance. Sterilize pruners with rubbing alcohol between cuts to avoid spreading bacterial canker through fresh wounds.

Strong water blast on new growth, every 2 to 3 days for 2 weeks

Hold a hose nozzle 12 inches from the affected new growth and spray at high pressure. Most aphids dislodge and don't make it back to the canopy. Repeat every 2 to 3 days for 2 weeks. The fastest, cheapest fix and works without touching beneficials.

Insecticidal soap spray on shoots, every 5 days for 2 weeks

Spray ready-to-use insecticidal soap (Safer Brand, ~$10) on the underside of leaves and along new shoot tips at dusk. The soap kills on contact and breaks down within hours, so it doesn't persist to harm pollinators. Reapply every 5 days for 2 weeks, focusing on the spring flush.

Plant alyssum and yarrow under the canopy

Plant sweet alyssum, dill, or yarrow within 6 feet of the trunk. These attract ladybugs, lacewings, and parasitic wasps that feed on peach aphids. Established plantings keep aphid pressure low without sprays and last for years, which fits a long-lived fruit tree well.

Hand-pick into soapy water at dawn, daily through July

Neem oil spray on the upper canopy, every 7 days

Spray neem oil (Bonide Captain Jack's Neem Max, ~$12) on the upper canopy at dusk. Neem deters feeding and disrupts the beetle's ability to lay eggs. Reapply every 7 days during peak flight. Spray at dusk to spare bees and other pollinators that visit during the day.

Skip beetle traps within 50 feet of the tree

Pheromone traps (Spectracide, ~$10) attract more beetles than they catch and concentrate damage near the trap. If a neighbor hangs traps, ask them to position the traps at the far end of their yard, not near your peach. The closer the trap, the worse the feeding damage on the tree.