I was googling and really surprised to see that the packets only contained 8 to 10 seeds! Years ago I purchased T. alata seeds and three were lots of seeds in one pack. I had a greenhouse back then and the Thunbergia trailed out of the pots and all over inside the greenhouse; it sure was pretty!
I had T. alata growing in a corner of the backyard at one time too; I'd sown the seeds in trays but ended up dumping them in the backyard where they grew and twined up into some shrubs.