I bought white lavender last fall, planted it in a pot and forgot about it on my north facing porch, it's so big now I divided it into 3 plants and gave 2 away. I'll try the pretty purple this year. I bought mine at a chain hardware store with a garden section, it was well started when I planted it. I also agree that it could be the soil, because I've learned that really does make a difference. Again, I bought general potting mix last year, and over the winter I've collected coffee grinds, egg shells, banana peels, and other things in a plastic tub like a compost bin which I will add the soil from last year to improve the soil for this years plants. Last thing, when you grew one before that didn't get very large, did you prune it? Pruning plants can actually encourage growth, much like cutting our own hair encourages growth. I never pruned my last year, but I will in spring when it wakes up.