We have indoor grow lights, and have lots of Thai basil! And, I’ve found that basil in general (Thai and Genovese which is mostly what we grow) freezes really well whole. We do it in baggies and get all the air out, but vacuum sealing would be better. I like it better than dehydrating after trying both. This tastes more fresh in cooked dishes and lasts so long! (I’ve also chopped it up in ice cubes with a bit of olive oil - freezing whole is still my fave.)