I have three butternut squash that are overtaking the plot they are in, do I have to stop them, also do I have to hand pollinate there seems to be several open male flowers but the female flowers remain closed, help.
You can nip off the growing tips when the vines start to escape their space. It should encourage more side shoots, which, some pumpkin lore says, will encourage more female flowers. There's a lot of pumpkin lore about ways to produce more female flowers, usually the pumpkin grower's biggest problem.
The female flowers open in the morning, often early. That's the best time to check them. They rarely stay open all day. You can hand pollinate if you like but it means getting up early.