The chill of fall is in the air. The leaves are thinking of turning and the spring garden is tilled under in anticipation of the first frost. The fall garden is in full swing and spices are lined up on the counter, ready to turn baskets of winter squash into sweet and savory treats. The only thing we are waiting for is the harvest.
In the northern hemisphere, winter squash generally comes into the house around September or October. Conventional wisdom says to leave the squash on the vine until the first frost has passed, but anyone who has had a squash go overripe might think twice about that. Winter squash gets all of its wonderful storage life from its thick, protective skin. Underripe squash will not have that thick skin, so it is more likely to turn bad in storage. It is vital to get the timing right for harvest or you might lose your winter squash.
Harvest time is dependent on location. Light levels and temperatures can vary tremendously. The date of the first frost is later for southern gardeners than it is for northern gardeners as well. All of these things can speed up or delay harvest.
Most vines are green when the squash are forming, but turn color when they are ripe. Winter squash is supposed to be at its peak when the vines are brown. This could be just after the first frost or it could be days or weeks before the frost. Keep in mind that the stem color is not always a foolproof sign of ripeness. Sometimes a brown vine is a dead plant, so make sure that the fruit is ready really before you pick it.
The best way to judge ripeness is to do it in much the same way you would at the grocery store. Winter squash should be the correct color for the variety that you are growing. All of them have a deep color, no matter what the variety. Avoid harvesting squash that is too light. The skin should be matte rather than shiny. Shiny squash are underripe. Winter squash should be firm at the time of harvest. If you can nick the skin with a fingernail, the squash is not ready yet.
Once you figure out the right timing for harvest in your area, mark it on the calendar. If the weather is similar, it should be about the same time every year, but your squash knows best. Make sure you check with it before you harvest.