when will i be able to sex my plants

me and a friend are going to be growing some Early Misty's this spring/summer, and so were trying to figure out everything before hand.

we will be growing these outside.

after how many weeks should i be able to tell the sex of the plants? do i need to do anything like cover up a stem so no light gets in it?

if you have any other information that you think is important for me to know feel free to post away

You don't want to cover any of the stems.
I think most males show sex at about 4 to 6 weeks
Females usually show about one month or more later.

If you are going to grow outdoor (not in pots) then you need to find ideal locations first of all. Make sure that the location gets plenty of light etc.
Then you need to dig soem really deep holes and fill them with soil that has a lot of organic nutrients, compost, bonemeal and perhaps even started fertilizer.

Digging the holes is the hardest part. They should be at least 2 feet deep if not more.

we have a pretty good spot, its a clearing in a forest where you have to cross a stream to get to it

so how big around should the holes be? and how long does it take for an Early Misty to grow big? it will be getting about 15 hours of light per day.