[VoodooChile]

The thing about grow bags is that they are but one part of a much more complete and complex Nursery Production System.

Grow bags are a cylindrical bag made from geo-textile or poly-mesh. Holes are augured in a field, the bags are "planted" to about 7/8s their depth, backfilled with the augured soil, and then planted with a tree or shrub.

The bags are usually the final stage of producing plants that have a dense fibrous root system without the girdling and circling roots of traditional b&b culture. The first stage is germinating seeds in a "rootmaker" flat on a wire mesh tray table. Contact with the air results in root-pruning. Later the seedlings are transplanted to 1 or 3 gallon rootmaker pots. Finally, the plants are moved to the field and planted in bags.

Properly planted and harvested, the final plant is less suspectible to transplant shock, quicker to establish, and more vigorous in the landscape.

Much of the rationale for this system of nursery production comes from the research of Dr. Carl Whitcomb, formerly full professor of Horticulture at Oklahoma State University. The results Dr. Whitcomb's research can be found in the excellent and eye-opening Establishment and Maintenance of Landscape Plants. In that book he addresses the many drawbacks of traditional plant production, and how a system that emphasizes root-pruning from germination onward produces a higher-quality landscape plant.

I recently had the chance to talk with Connor Shaw of Possibility Place Nursery in Monee IL., who has been growing woodies with the Whitcomb system since 1983. There were definitely kinks in the early years with this method, but since perfecting these methods, and using the whole system, Connor has been able to produce a superior landscape plant, particularly when working with species that don't lend themselves to transplant, like large Oaks and Hickories.

I wouldn't dismiss grow-bags out of hand. When used as part of a nursery production system, grow bags are a valuable technology. If your nursery marketing emphasis is producing the highest quality plant with a minimal labor/equipment investment, the Whitcomb method and its knockoffs are well-worth investigating.