Flea beetle

My pak Choi, both seedlings in modules in one area of the garden and planted seedlings in the soil have been decimated by flea beetle.  Any useful tips to avoid this in the future?

It is flea beetle in the soil but the dreaded cabbage white caterpillars on the modules! Hopefully the flea beetle damage will be 'grown through' as the seedlings get larger.

I've been looking at this as my turnips did nothing this year. The pest is associated commercially with oil seed rape growing (so don't buy stuff containing this could be a start). So if a lot is grown in your area you could be struggling.
Life cycle is here; https://ahdb.org.uk/knowledge-library/ca...lea-beetle
Some sites recommend companion planting with rosemary and thyme. I know Rorbert Milne recommends thyme (20cm+ across plants at 1 per sq.m.) for cabbage root fly in all brassicas. He recons it is 90% effective. So I would try, grow as long as possible undercover with a thyme plant and, when planting out, plant out the thyme as well. You could try covering with fleece as well. As they are very small, environmesh coul let some through may be.

Robert also says that most years they are not a serious problem and that keeping the ground damp is fairly effective (may be pak choi would be different because of when it is grown in the beetles life-cycle).

Thanks Mark, will try fleece, as it sounds like the easiest option.

Keeping the soil moving over winter by hoeing wil lreduce the numbers next year. The larvae overwinter in the soil. Diatomaceous Earth will help repel them in the growing season.

It could be bad this year as we have a field of rape across the road. Thanks for the advice, I'm off to Google diatomaceous earth, never used it before.

I need to make a note of these tips too - thanks, guys! The field nearest our garden had wheat growing in it this year and last, but there's definitely oilseed rape on nearby farms.

It is an absolute menace down here and I'm surrounded by forest with a bit of pasture, maze & sunflowers. The hotter and drier the worse they are.
I have tried fleece, but everything fried underneath, and diatomaceous earth with some success, but it is a blunt instrument that kills all soft bodied invertebrates. I have to protect my glow worms because they eat the slugs.
Growing everything brassica away from the veg garden in modules helps - somehow the little darlings have never thought to look around the side of the house! But my red russian kale, two good robust plants, have gone in a couple of days.
I only direct sow radish in the spring and autumn and no longer grow Pak choi at all as it really suffers.
Keeping the ground moist (40 degrees, hollow laugh) does help. That means watering three times a day ...
Today I sprayed all my brassicas with insecticidal soap and tomorrow I am considering going out with the cordless hoover!!
Hoeing isn't an option as I heavily mulch to conserve moisture and mostly no dig, the mulch of course may be providing overwintering habitat.
And this evening I heard them pinging off the horseradish as I walked past.

Smelly things will help to deter them. In the past l have used soft string soaked in J***s fluid suspended over the rows and it worked a treat. It doesn’t smell anymore but if you can find something else that does it could work.

I still have some old Js witch stinks very nicely. Thanks Roiltelet. The pak choi did indeed grow through the damage, plus I think we had a spell of rain. I'll remember your tip for future showings. I wonder whether a spray made with whizzed up rosemary would also do the trick.

Give the Rosemary a try. I think what you need is something that stinks for a long time.