How much room should be allowed for a plant outdoors giving it full potential to become as large as possible? How deep can roots get? Any help appreciated. Thanks.
This will depend on the strain. Sativas can go 15-20 feet tall outside in the right locations if planted early enough. Root growth will depend on the condition of the soil..Live in a dry climate that is prone to drought-like weather? Roots will grow like crazy looking for water.
give them as much space as possible min 4feet round for indaca and 3 feet round for sativa ( this is they way i grow and it gives them plenty of space to become giants). the more space u give them the bigger they will grow! i make my holes 1.5 f wide by 3.5 - 4.5 feet deep depending on how much soil i have.
Make sure you up the water supply a bit to accomidate such a free area. You'll need probably 300-600ml of water per plant on any given day.
Sounds like you're growing in a dry climate. This will depend on the humidity in the air and size of the plant. Higher humidity climates with less transpiration and drying of the soil will need marginally less.