(1) http://www.erowid.org/psychoactives/cultivation/cultivation_growing-the-hallucinogens.shtml#BELLADONNA
Cultivation and Propagation: Belladonna is hardy throughout the U.S., dying back in winter and rising from the root in spring. It prefers a well-drained, well-limed soil in full sun or part shade. The soil should be kept moist at all times. Plants exposed to too much sun will be stunted. In hot sunny areas it may be grown between rows of beans to shade it.
Belladonna is most frequently propagated by seed, sown in flats in early March. Because the seeds take 4-6 weeks to germinate, they should be started early. When the seedlings are an inch or so high they may be set out 18 inches apart. The seedlings should be well watered just after transplanting, and shaded for several days. First-year plants will grow only 1.5 feet high and will flower in September. At this time the leaves and tops may be collected, but the plants should not be entirely stripped. The plants should be thinned to 2.5 to 3 feet apart at the approach of winter, or overcrowding will occur the second year. In June of the second year the plants may be cut to 1 inch above the ground when they are in flower. In good years a second crop will be ready for harvesting in September. The roots may be harvested in the autumn of the fourth year, and new plants set in their places. Belladonna may also be propagated by cuttings of the green branch tips.
I have found that snails, aphids, and white flies are among this plant's worst enemies. Small children are much more susceptible to belladonna poisoning than adults, and should be kept away from it.
Harvesting: The parts harvested as described above should be dried quickly in the sun. Wilted or discolored leaves may be discarded, as they contain only small amounts of alkaloids.