Flea beetle: identify, prevent, control

Peaks in warm, dry spring and summer weather, September to February.

Flea beetles are tiny jumping beetles that pepper leaves with small round holes. They hit seedlings of rocket, Asian greens, radish and other brassicas hardest, and a heavy attack can stall young plants completely.

How to identify it

• Many small round shot-holes peppered across leaves
• Tiny dark beetles that jump like fleas when disturbed
• Worst damage on young seedlings and tender greens
• Stunted, struggling seedlings under heavy attack

How to prevent it

• Cover seedlings with fine exclusion netting from sowing
• Sow into warm soil so plants grow away quickly and outgrow the damage
• Keep beds weed-free, since weeds host beetles between crops
• Water and feed seedlings well to push fast growth through the vulnerable stage

Organic control, step by step

• Spray eco-neem to deter feeding and reduce numbers, repeating weekly
• Use pyrethrum at dusk for a fast knockdown of heavy infestations
• Set up yellow sticky traps to catch jumping adults
• Mulch around plants to make it harder for beetles to reach the soil and lay eggs
• Keep plants growing strongly, as healthy mature leaves shrug off light damage

Plants it attacks