Use the best Soil brands. Add vermiculite, pearlite or sand to Soil to increase the drainage and aeration.
Organic gardeners use their own compost prepaired from a mixture of chicken, cow or other manure and household food waste, leaves, lawn clippings, dog hair and other waste products including urine, which is high in nitrogen. Dog hair is not recommended for guerilla gardeners planting off their property where police could find it. DNA tests could prove it was YOUR dogs hair!
Use P4 water crystals in the soil to give the plants a few days worth of emergency water reserves. This substance swells up with water and holds it like a sponge, so that roots will have a reserve if harsh drought makes constant watering necessary. Go real easy on this stuff though, it tends to sink to the bottom of the pot and suffocate bottom roots (new growth roots) and stunts the plant. Use in extreme moderation, let it swell up for at least an hour before mixing with other soil.
Plant size in soil is directly related to pot size. If you want the plant to grow bigger, put it in a bigger pot. Usually, 1/2 gallon per foot of plant is sufficient. A six foot plant would require a minimum of a 3 gallon pot. Remember, square containers have more volume in a square space (like a closet).
Planting in the ground is always preferable when growing in soil. The plants can then grow to any size, unlimited by pot size.
Bat Guano, chicken manure, or worm castings can all be used to fertilize organically in soil. Manures can burn, so they should be composted with the soil first, before planting, over several weeks. Sea weed is available to provide a rich trace mineral source that breaks down slowly and constantly feeds the plants.
If growing outdoors in available soil, look around for leaves and other natural sources of nitrogen and work them into the soil, along with some dolmite lime and composted organic fertilizer. Even small amounts of plant food such as Miracle Grow can be added to soil at this time. (Organic gardeners frown upon this practice, however. Toxic wastes are produced by commercial fertilizer production.) Mulch can be made from leaves and spread out over the garden area to hold in moisture and keep down weeds near the plants.