I have never tried sedum from seed, other than it self sowing, so not sure on what works best.
Have you ever tried Winter Sowing? I would think you could use this method with success, and transplant the seedling in the spring.
Or you could try some of the seed both now and in the spring if you want to sow in the ground.
I would love to see an update on what methods you use and how it does.
