How do increase the yield and potency of my outdoor bud?

i am growing a mixture of plants outdoors on my balcony. they have started to bud recently (like a week) after i moved them to a shady spot but it's still high summer (im in the southern hemisphere) with about 15 hours of daylight and i have 8 weeks before my lease runs out so i would like to get these babys grown and harvested in that time if possible. any suggestions?