Keeping the night temperature only a couple of degrees below the day temperature is one of the few reliable ways to reduce sativa stretch without training. A large drop between day and night encourages longer internodes, while a small differential keeps the plant compact during those first weeks of flower. The environment notes on https://hazesativaseeds.com describe running a near flat temperature for the first three weeks after flip and then allowing a wider gap later for resin production. It is easier to manage in a sealed room than in a tent that vents to a cold garage.
