I wouldn't say it's a waste of time at all. if you know your strain and how many days till it's ready for harvest then that is how many days of work you will put into your girls. Now growing outside is very easy. You said you planted your seeds the other day? Did you germinate them first?
i'm in michigan and the early strains started to flower about 5 or 8 days ago
many strains won't start for a week or more from now
i assume you get a full month longer to flower than we do
prolly won't get big, but you should be able to finish some plants yet