starting seeds outdoors can be done, I mean marijuana plants have been growing wild from seed for thousands of years before we were here. You cannot even think about starting seeds until the last spring frost is over in your area. There is last frost dates for all different locations, its may 16 here, so anytime after the last frost, your fine. I suggest having a big amount of seeds to play with, because you will have some fatalities. In the spring, when the slugs come out to play, they absolutely love marijuana seedlings and one slug can easily destroy a seedling in a matter of minutes. If you do have slugs, your going to need to protect your plants, seedlings are very small and defenseless when they just start growing. Anything can kill them very easily. Maybe you should make a mini greenhouse to start your seedlings in, it will help protect agaisnt some animals, and keep it nice and toasty in the early spring. Seeds germinate very lousy at low temps, especially outdoors in spring, so germinating seeds indoors is faster, then gently transfer germinated seeds into a party cup of fluffy soil and place outside in greenhouse. Hope that helps, happy toking.
P.S paper towel method may be a delicate way to germinate seedlings, but with proper viable seeds, The paper towel method is almost fool proof, with a hundred percent success rate other then broken tap roots.
WOOT 800 posts!