holey cabbages

hi all - my cabbages, some of my cauliflowers and purple sprouting have leaves that look like theyre being munched my something. They have tiny pin holes, that seem to be in a line, a bit like this " ... . .. " Theres no sign of any insects of caterpillars.. Any ideas whats causing it and how to stop it?

regards
ed

 

Hello ed, it`s probably Flea Beatle.They are tiny and jump when disturbed.
The book says to spray the seedlings with derris(i`d also like to know what this is)at first signs of damage.Water damaged plants if the weather is dry.

 

Elaine - You can buy "Bio - Liquid Derris" it's one of the few remaining 'traditional' pesticides still available to gardeners.

 

Holy cabbages? Didn't know if that was an exclamation or a visitation of the Holy Spirit!!

 

Excuse me edbev -

MMD, you are a scream!

 

Thank`s Dave.