Radishes deter flea beetles.

Refuted

Radishes don't repel flea beetles. Flea beetles love radish, which is why some gardeners plant it as a trap crop to lure them off their broccoli and cabbage. That only works if you then deal with the beetles on the radish. If your radish leaves are riddled with tiny holes, that's flea beetles doing exactly what they do.

What is actually known

Radish does not repel flea beetles; it draws them. Radish is among the brassicas flea beetles find most attractive, and they damage it at every stage, which is why radish and daikon are planted as a deliberate trap crop, to pull flea beetles away from seedlings of other brassicas such as broccoli and cabbage. That is the opposite of a deterrent, and a trap crop only helps if you then deal with the beetles on it. Extension advice is to destroy, spray or harvest the trap crop once the main crop has outgrown the danger. Where wild mustards are common, the trap may make little difference.

The evidence

Evidence: checked against 4 sources in the research-based literature.

The 4 sources

extension.colostate.edu Read by a person on September 24, 2026

Flea Beetles Colorado State University Extension

Trap cropping involves purposefully planting a highly favored crop to attract flea beetles away from the main crop.

uvm.edu Read by a person on September 24, 2026

Flea Beetles University of Vermont Extension, Vegetable and Berry Program

Other highly attractive brassicas include radish, daikon and arugula. These crops remain vulnerable to flea beetle damage at all stages of their growth.

extension.usu.edu Read by a person on September 24, 2026

Flea Beetles on Vegetables Utah State University Extension

Trap crops lure flea beetles away from the desired (cash) crop, and can be destroyed or sprayed to decrease the flea beetle population.

extension.arizona.edu Read by a person on September 24, 2026

Flea Beetles University of Arizona Cooperative Extension

Radish is often used to trap cole crop feeders.

When do I plant radish? ›

Cite this page

Milpa Gardens. "Radishes deter flea beetles." Evidence grade: Refuted. https://milpa.garden/beliefs/radish-flea-beetle/

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