Those are harvest times for an outdoor crop. It doesn't matter when you start them because when your plants are outside they'll start to flower some time in August. It depends how big of a harvest you want I guess.
You can germ them now. Use a sunny window at first. If you aren't ready to take them out when they hit maturity, then put them under lights until you are.
Once a seedling hits the 5-6th node with low daylight hours it will start to flower. The days aren't long enough until mid April or when ever the last frost is if it's later than that to start a seedling outside.