[Ethel]

Has anyone ever tried this? I was reading on an Australian site that a couple of frosts can improve the flavour and skin of squash. I would have to build a rat proof cage around each squash if I were to do this - already lost all my sweetcorn to the little blighters! But if the frost does improve flavour I would be willing to leave a few there with their full metal jackets.

[mumofstig]

If the skins have hardened, they should survive a slight frost but not a hard frost. How do you judge what level of frost will happen? properly frosted fruits just won't store.
You could cover them with fleece or straw, but covering and uncovering as required is a lot of a faffing around IMO.
I'm happy just harvesting as soon as the skins have coloured and hardened, rather than losing any.

[Ethel]

Thanks mumofstig. I'll just take them in before the frosts; it's my first year with squash so I really don't know what I'm doing yet. Have had some lovely uchiki kuri that I've brought in already as they were such a nice colour and the leaves were dying back but was wondering if I'd done the wrong thing. I have some Queensland Blue and Ute (green) which are hard to judge by colour so I'll just give them another couple of weeks and hope for the best.

[New shoot]

If the stalk to the squash has gone really hard, they have effectively shut off from the parent plant and are ready to pick.  The plant then dies off as its job is done, so leaves withering away are another clue.

Even if the skins are not as hardened as you would like, you can put them somewhere sunny but protected and finish them that way.

I'm with MoS and pick as soon as I think they are done rather than risk a frost