Is there a formula or product that is light weight so a 5gal bucket doesn't end up weighting 40lbs.
a 2gal bucket can grow a full size plant with coco coir?Pro Mix is good and I think HP may be the lightest the have. There is also Fox Farms LIGHT Warrior. Many, many other options too. Look for something with lots of perlite or just buy a huge bag of perlite and mix your own up. You will need to change your watering habits w/ a light mix.
The other option is coco coir since 2 gallons will grow a full size plant if properly fed and watered.
I have a 20x20' space and being as I'm in New England I'd like to overwinter as many as possible for the following season.I think so. I don't weigh em, but I'd bet I took 3 pounds of Yellow Scorpions from one of mine in a 2 gallon smart pot. You have to water every day and use a hydroponic fertilizer though.
I just connected the dots and saw your Yummy Orange Xtreme thread. How much land do you have to use? If land is the limiting factor then you might want to go with hydroponic type setups, but if you've got space, I'd go with soil. Have you checked out AlabamaJack's videos? That's a pretty amazing use of a back yard sized space. If you've got more room I'd check out SilverSurfer and WayRight. There's plenty of others who have done amazing stuff this year, or years past, but everyone has different goals, space, soil quality and climate. It really makes a difference when deciding to go soil, beds, containers or hydro.
All that said, if I had land and wasn't living paycheck to paycheck I'd go organic soil, bio-dynamic style. It's a slow start and hard work, but pays off in the long run.