Beet leaf miner

This year my chard and beetroot are plagued by beet leaf miner. It's not a problem I've suffered from before. I understand the flies look like small house flies and the lay eggs on the underside of the leaf, the grubs eat through the leaf and then drop to the ground and overwinter as pupae.  I'll not be sowing chard or beet in this spot next year. Anyone else had this problem?  I could cover the plants with mesh but I always thought chard was relatively pest free.

This year my chard and beetroot are plagued by beet leaf miner. It's not a problem I've suffered from before. I understand the flies look like small house flies and the lay eggs on the underside of the leaf, the grubs eat through the leaf and then drop to the ground and overwinter as pupae.  I'll not be sowing chard or beet in this spot next year. Anyone else had this problem?  I could cover the plants with mesh but I always thought chard was relatively pest free.

Yes, I had this problem on beetroot last year and this. Both times in ground that hadn't had such plants in before, so I guess they flew in.
The leaves were heavily damaged, but eventually the insects stop, the plant grows new leaves and recovers somewhat.

I've grown beetroot and chard under netting for a few years now, ever since beetroot seedlings were getting massacred at the first leaf stage and chard made inedible. The beetroot go in the same bed as the carrots and get covered with enviromesh. Scaffold netting seems fine enough to keep the leaf miner out so my chard is under that and hasn't been touched at all so far. The chard I plant in the greenhouse in September/October is never affected though.

The eggs look like really small grains of rice and they lay them in groups. They're really well stuck on to the leaf and not easy to rub off like caterpillar eggs.

The carrots and kale always go under mesh, I suppose they'll have to invite beets and chard to stay too. Yet, another problem, I'm getting a little disheartened with the garden this year, I just don't seem to be keeping on top of it. I've resolved to grow a lot less next year. Same variety but fewer plants.

I've seen leaf miner in the GH this year too - never really noticed it before. It was on the chard but I cut the leaves off and forgot about it!
We grow chard to eat the leaves but with beetroot the leaves are not quite as appealing as the roots. Are beet roots affected by leaf miner or is it just the leaves? If so, there's no need to put the beetroot under netting.

I've seen leaf miner in the GH this year too - never really noticed it before. It was on the chard but I cut the leaves off and forgot about it!
We grow chard to eat the leaves but with beetroot the leaves are not quite as appealing as the roots.  Are beet roots affected by leaf miner or is it just the leaves? If so, there's no need to put the beetroot under netting.

I can see your reasoning and agree, the beets need not be friendly with the carrots and kale. They'll be mightily relieved as they're not on speaking terms atm.

They don't affect the root but a big infestation on the leaves will slow the plants down. Young plants will be most affected so I don't take any risks with beetroot seedlings now, especially the July sowing.

The carrots and kale always go under mesh, I suppose they'll have to invite beets and chard to stay too. Yet, another problem,  I'm getting a little disheartened with the garden this year, I just don't seem to be keeping on top of it.   I've resolved to grow a lot less next year. Same variety but fewer plants.

It's not been a great veg gardening year really, at least for the crops which I'm most enthused by. The weather in July, which is now continuing in to August, sucked the motivation out of me. Blight and powdery mildew have arrived early. Slugs have been a major nuisance especially since there was a shortage of slug nematodes so I didn't buy any. At least I'm not growing any sprouts of kalettes this year so cabbage whites, brassica whitefly and mealy cabbage aphid won't be the usual major headache. 

Lots of things have done quite well though, like the berries and roots, and the flowers are going really well. It's mostly the tomatoes I'm miffed about.

They don't affect the root but a big infestation on the leaves will slow the plants down. Young plants will be most affected so I don't take any risks with beetroot seedlings now, especially the July sowing.

I'm not sowing anything, I've not got the room. You're more organised than I.  I tend to be like a bull at the gate in spring, sow everything and anything  then run out of room.