I left mine on the vine past the first few frosts, but not freezes. Then cut them off leaving a few inches of vine. do not cut too close. VERY important not to damage the gourd or it will rot. Lay them in a cool dry place and walk away. Come back after a month and shake them. When they are ready you will hear the seeds rattle inside. They should be hard, very lightweight as the liquid has all dried out. And they can take 3-4 months to dry completely. they sometimes get some black type of mold or whatever, that is ok just leave them be. After they are totally dry you can scrub them w some bleach mixture if you really want to. I would recommend to lightly sand them before applying paints to help it adhere.
