My latest commission is two pumpkin hats for an aunt to gift to her nephews who live somewhere much colder than south Louisiana. They are pretty cute and I hope they fit -- still working on arranging delivery and payment. The vertical crochet makes for a nice stretchy hat, and the brim lets you roll it up or down to further customize the fit.
This pattern is really just a method -- chain until it's about the height you want the hat to be (because adding the top will allow for the brim fold) and double crochet in the back loop only back and forth until it's as long as the hat needs to be around. Sew up the two sides to make a tube. Then attach the green to one end of the tube and single crochet evenly around. Decrease every 10 stitches, then every 9 stitches, etc. until maybe 8 or 9 stitches left and single crochet around to make the stem. Decrease until you sew up the top. The curlique vine is easy - chain the length (knowing that it will curl up) and put three double crochet into each chain. Sew it onto the stem. If desired or needed you can reinforce the green-to-orange attachment with simple sewing. Weave in ends.Voila.
I use 100% acrylic yarn so my hats are washable. I dry them flat because the dryer makes the yarn a little fuzzy and can break it down faster.
I've made this hat in stripes - changing colors every-other-row and leaving off the stem but adding multiple curliques. You could maybe decrease faster to make a smaller top section. If you made a longer tube you could cinch it by weaving in and out -- maybe even with a long chain. I bet a rainbow, multi-colored hat would be cute like this. I probably have every color of the rainbow after my fury of crocheting before the maker faire so I'll put it on the "to make" list. I have two-toned blue swirl hat to make for a young friend. I need to measure her head and I keep forgetting. It's probably standard kid sized and it would be fine if I make it to fit Jane's head.
Keep that hook flying!