Pyrethrum spray

How it works

A chrysanthemum extract that attacks the insect nervous system on contact and knocks it down within minutes. It breaks down in sunlight within a day.

Recipe

Ready-made product per label only. Do not attempt to make this at home.

How to apply

Absolute last resort, spot-treating an outbreak that nothing else has held. Dusk only, targeted at the affected plant, never blanket-sprayed.

Targets — pests

Aphids, Beetles, Whitefly, Thrips, Most insects

Targets — diseases

Not recorded — the field is blank rather than guessed.

Supplies: Pyrethrum concentrate, 5 L pressure sprayer, Gloves and mask

Days to harvest after spraying: 1

Best months: not recorded

Cautions

Extremely toxic to bees, ladybirds, hoverflies and fish. It kills your predators as thoroughly as your pests, so the rebound outbreak two weeks later is usually worse than what you sprayed for.

The thing people get wrong

Organic does not mean harmless, and pyrethrum is the proof. It is the one spray in this app I would ask you to think twice about: reaching for it usually means the underlying problem is a shortage of predators, and this makes that shortage permanent.