Note to readers, attached is the complete final report for FNE96-151
Mr. Rozendaal grows artichokes, which he starts in a greenhouse, then transplants outdoors. He is concerned to use his greenhouse space as efficiently as possible, so he conducted a multi-factor experiment, testing various alternatives in the cultivation of artichokes. He planted some seeds in 2″ soil blocks, and some in 4″ soil blocks; he planted some in plug trays, then later transplanted these to root trainers and 4″ pots, and some plants he started directly in root trainers. He also compared various planting dates in March. From time to time during the course of the growing season he rated the plants in the different treatments on a scale of 1 to 10 as to vigor, color, size, and leaf stage.
Mr. Rozendaal found that root trainers gave him the best use of space. He reports that they produced strong plants with healthy roots; however he notes that they are expensive, and require much labor to set in the field. Two-inch soil blocks, while they do not permit plants to be packed together as closely as the root trainers do, are handled more efficiently, and allow a much better use of space than 4-inch blocks. He found that plants started on March 31 fared as well as those started on March 15. The later date would appear to be preferable, since it means the plants spend less time in the greenhouse, which in turn means less expense for rental of greenhouse space. However Mr. Rozendaal felt that, at least in the climate of Burlington, Vermont, with so late a starting date one could not be assured of a crop. He concluded that the best way to grow artichokes is to seed them into 2″ soil blocks on March 15th, move them to cold frames on April 15th, for vernalization, then transplant them to the field between May 1st and May 15th.