I want to plant 20 or so flowering cherrys all the same varietie next to the road in a hedge. My plan was to buy seeds and grow them from scratch. Will the seeds I buy definitely be the varietie I want or do they cross polinate like apples? What varietie would you choose I was thinking prunus chocolate ice. I'd like them to grow very large eventually. I can't find any detailed info on the net or a book about doing this. Thanks for reading.