Autumn sowing definitely make stronger plants. The root system is much more developed. They flower earlier too - I've had them in full flower in early May, depending on the weather (absolutely not the past couple of years!!)
If I miss autumn, I always go for late winter, Jan/Feb. Imo, later than that they never do so well.
I grow mine in root-trainers.
Lavender, I've never heard of cutting off the first shoot?
Manics, I bet those plants sell well!
