- 1). Collect seed pods in fall when they are brown and just starting to crack. Place them in paper bags in a sunny warm area, and allow them to split open completely. The seeds will spill out into the bag. Pour them into a plastic bag that seals, and place them in a cool dark place until late February or early March.
- 2). Start the seeds indoors in late winter or early spring. Fill the flat with half potting soil and half compost. Datura seeds need an organically rich soil for best growth. Nick the seeds with a knife on the flat edge to help water penetrate the tough coating. Sow the seeds 1/2 inch apart on the surface of the soil. The seeds have a better germination rate when exposed to light.
- 3). Sprinkle a fine dusting of vermiculite over the seed. Mist the soil until evenly moist, and place the lid on the flat. Put the flat in a room that is at least 70 degrees Fahrenheit and has bright but indirect light. Keep the soil moist and watch for germination. When the seeds sprout, open the vents on the lid to prevent damping off.
- 4). Gradually move the seedlings to full sun and continue watering. Once they are 5 to 6 inches high, use a spoon to scoop them out of the flats, and plant them in 4-inch pots. Provide water, heat and sun until outdoor temperatures are consistently 65 degrees Fahrenheit, and then move them outdoors.
- 5). Prepare a planting bed by digging in 5 inches of compost and removing weeds and debris. After the seedlings have acclimated to the outdoors for a week, plant them in the bed. Water until puddles form, and, thereafter, allow the soil to dry between irrigation.
- 6). Feed the plants two weeks after transplanting outdoors with a tomato fertilizer. Datura plants are nightshades just like tomato plants and have similar nutrient requirements. Mix 1/2 cup of tomato fertilizer per plant into the top 3 inches of soil three times during the growing season, evenly spread out. Water the plants well until puddles form on the surface of the soil to prevent fertilizer burn.