Cheap plastic greenhouses

[DiddlyWiddly]

Are they any good for keeping tender perennials alive please?
My mum is looking at getting one but I have never used one and apart from some herbs I don’t grow tender plants so can’t really advise her.

I had one up last year. It was a bit prone to blowing away but up against a wall with a few bricks etc weighing it down would be fine I think.

Great, thanks!

Bungee cord it to a fence will stop it flying away.

They are just short term solutions. Aldi do small wooden ones.

Mine is a cheapie I bought for a couple of ££ in wilkos end of season sale a couple of years ago. It has been up in the garden ever since weighted down with a couple of bricks and until I moved it bungee tied to the fence. I tend to use it for starting dahlias and begonias and later I will remove the shelves for my cucumbers.

I got one from Ikea which is big shelf unit with a cover for about £13.00. They do smaller ones for less than that. They are metal so might hold up better than plastic ones.

I have 2 and successfully started seeds in February in them. I haven't tried with protecting plants through a whole winter yet though. I agree it needs to be really well anchored. I have bricks all the way around the base 'skirt' and a couple of bags of compost anchoring the staging.
I have a mini heater in one of the green house which keeps it a couple of degrees warmer in the night and quite a lot more during the day

Do you mean a covered shelf (called a "growhouse" I think) or a polycarbonate greenhouse?

I don't have any experience of the former but have been looking into them due to the fact that I can't get a new greenhouse for love or money right now! However, if the latter, then they're just as good as glass greenhouses, just (as PP have said) more prone to blowing down/away, which is what happened to my previous one after a couple of years use and why I now want a glass one!