DK weight yarn
However I can see this working easily with almost any yarn and hook size. Thicker yarn will produce wider, longer leaves.
The little leaves are made by doing a dc2tg, only instead of doing it across multiple stitches like you would normally, complete the dc2tg stitch in the same stitch.
dc2tg: yo, insert hook, pull through (3 stitches on hook), yo, pull through 2 (2 on hook), yo, insert hook, pull through (4 on hook), yo, pull through 2, yo, pull through all 3.
1. ch2. In the first chain (sc, ch2, sc)
2. ch1, turn. sl st into the ch space, Into the ch space do (dc2tg, ch3, dc2tg)
Repeat row 2 for the length of the headband
When you have enough length, sl st into the ch3 gap, ch40, sl st back into the gap. One tie complete. End off and weave in tails. To make the tie at the beginning end, join the yarn as a sl st in between the first 2 sc’s and ch40, sl st into the same place. Weave in ends.
Now you can decorate it. I added a small flower to mine.