Plant cotton seeds in mid-spring when the frost lifts. The seeds germinate best at temperatures of 60 to 65 degrees F and die in any spring frost. Choose sites with bright sun, quick drainage and good air circulation. Plant the cotton seeds individually in corners, along fences or in groups in beds and around borders. Plant them away from smaller full-sun plants, as cotton grows to 4 to 5 feet in height and may shade out other plants in the area.
Amend the soil in any planting site or in full planting beds. Till the soil to a depth of 12 inches to account for a cotton plant's deep root system, and turn 12 inches of organic compost into the soil for a mix of 50 percent natural soil to 50 percent amendment. Cotton requires deep, rich and moist soil, and it depletes poor soil quickly. Add granular 10-10-10 fertilizer for balanced long-term nutrition.
Plant cotton seeds 1 inch deep in the prepared soil. Allow each plant 2 to 3 feet of space for full, healthy growth and air circulation. Choose cultivars with white, yellow or pink blooms to match or contrast the other plants in your garden.
Water cotton with 2 inches of water every week throughout the season. Lack of water leads to wilting and then the death of foliage, while ongoing care leads to growth into the fall. Lay 2 inches of organic mulch on the soil to maintain moisture between waterings.
Feed hungry cotton plants once a month with tomato-specific fertilizer. The plants deplete soil quickly but maintain healthy growth and blooming with adequate nutrition.