If you haven’t already done this, it is a really good idea to get it done this weekend. Pruning out excess leaves and vines will help the fruits to grow and ripen before harvesting in late Oct (ish – you may need to harvest a little earlier if it gets suddenly cold and frosty, or you may get a couple of extra weeks if the weather stays mild)
Prune out newly forming fruit
Cut off or pull off any baby fruits that are appearing as these won’t have time to grow and ripen before harvest time next month. Hopefully you will have a few decent sized fruits on the plants already (although some of you may not have been luck this year!) and these will benefit from having all the attention now!
Prune out vines
Use a pair of secateurs to cut any vines that are not bearing fruit, and cut at the growing tips too to prevent them from growing further. This will help to concentrate energy into ripening the fruits.
Thin out the foliage
Again, using secateurs (squash vines can be surprisingly prickly with their little hairs) cut the leaves around the fruits so that the sunshine can reach the squashes/pumpkins themselves. The warmth from the sunshine will help to ripen them.
Feed plants
You could also give them a liquid feed now to boost the development of the fruits. Choose a potassium rich feed (which is better for fruit forming) as opposed to nitrogen (which is better for leaf growth)
Don’t harvest yet…
Leave the fruits on the vines for as long as you can – but harvest before frosts. When the stalk of the fruit turns woody, and the leaves naturally begin to die back, the skin should be hardened and you can happily harvest them. This tends to be in mid/late October.