hiya,i have just brought 5 foxgloves or digitails[if thats right],they are white and purple,do i just leave in ground and they will sow seed themselves,they are in flower now and look really lovely,im a bit confused as the lady at garden centre said they die off each year,and i have to replace them every year!!! so im unsure.also i was wondering about holyhocks is it to late to buy them and also do all of them get rust??