Abstract A 96-inch-tall coastal Douglas-fir (Pseudotsuga menziesii Mirb.Franco) seedling was grown from seed in two years. Greenhouse temperatures of 60° to 70° F, a six-month growing season, long day, adequate winter chilling, large pots, periodic fertilization, and frequent watering are thought to be contributors to the rapid growth.
Copes et al. (Sat,) studied this question.