[Island Time]

Anybody familiar with trees grown in grow bags. What are the pros and cons to these compared to b&b or container grown? Any experience with these would be helpful. Thanks.

[Lanelle]

Our Ag Research Station has been doing tests on grow bags. So far, I've heard positive things about them. Don't remember much detail, tho.

[trees]

Grow bags are great for plants like Leyland Cypress that have easily damaged, fibrous root systems, but other than that I don't recommend them.

They're a bear to work with. Despite claims, they do NOT prevent roots from growing through them, and removing a bag from a 3" tree with roots sticking through it is a nightmare. Several nurseries I know stopped using them except in cases like Leylands due to their difficulties. If the tree can be sold and planted before it starts to get a little big for the bag, they're great, but... seriously now... that doesn't happen even the biggest part of the time.

Like many things, they're interesting in theory, but in practice... not so much.

[r schipul]

Trees,

How recently have you had experience with grow bags? I know the bags allow small roots through the sidewalls but I've heard early versions of the bag would allow roots through and they would continue to grow, stretching the bag, making removal impossible. I'm also wondering if you used more bag grown plants (a couple hundred a year vs. a couple) do you think it would be possible to find a more efficient system for removing the bags. The reason I ask, I own some land which I plan to line out stock on. I'm seriously considering using the system for the reasons they mentio.n Long harvesting season which is huge considering we could leave plants in the ground until we need them and closer plant spacing because large equipment/ tree spade aren't needed for removal. I'm trying to figure out if the benefits of more plants per acre and harvesting out way the staking and bag removal. Bag grown plants are not at all common in the Northeast. The people I know who have purchased plants in grow bags all mention the difficulty in removing the bags. I watched the grow bag video last week. They show the bag with the roots coming through. They make 1 vertical cut, hold the bag in 1 hand and make a couple of small chops with a machete. It didn't look terribly difficult. What did you use to remove the bag? Thanks in advance for any comments

[trees]

My last experience with them was about 5 years ago at a nursery I was working at in Maryland. They grew a lot of their stock in bags and stopped the last year I was there due to the planting difficulties. I'd say during the year and 1/2 I was there, probably 1/2 of the trees we planted were in bags.

We did pretty much as you described to remove them. I vertical slit, grab & pull... arg! cut a few of those roots, pull... S---! chop a few more... pull... F---!... you get the picture.

Bottom line, from my experience anyway, they just aren't much fun to work with. I'd look in to doing pot-in-pot if I were you.

[Pelican]

Can someone explain what a grow bag is? And what material it's made of?

[GLAN]

Originally posted by Pelican
Can someone explain what a grow bag is? And what material it's made of?

Yes please

[r schipul]

Thanks trees. Glan and Pelican check out Rootmaker.com and treebag.com. If you get into the Rootmaker site there are articles written on studies about trees grown in bags which is pretty cool. You can also do a general search on Carl Whitcomb and get some more articles. I love the concept. If they could only figure out how to make the bag removal easier. I've considered pot in pot but there are to main reason's why I've been shying away from the system. 1. a plant can stay in a grow bag longer than a pot. I had planned on using 30" bags for trees. Essential I could harvest that tree anywhere from 2-4" cal. possibly up to 6". Pot in pot I'd have to continually pot up or sell to prevent root bound plants. 2. Installing a pot in pot system correctly with drainage is pretty costly. Thanks Trees.

[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.

[VoodooChile]

A 12" Rootmaker Products poly bag. These were developed to encourage rooting through the bag and the resulting pruning.

[VoodooChile]

A more traditional 16" Root Control Bag Growing System geo-textile bag. I am not aware which of the two is considered better.

I shoved plastic bags inside the root control bag to help it hold its shape for this and the last picture.

Root Contol Bag Growing System and Rootmaker Products are two different companies.

[VoodooChile]

Rootmaker trays, top view. Seedlings would be germinated in these trays, optimally on an open bottom wire mesh bench. Once the seedling had fully rooted into the medium, it would be transplanted into a larger container.

[VoodooChile]

Rootmaker trays, bottom view. Growing roots penetrate the openings, are air-pruned, and then branch to make a denser, more fibrous root-system, without girdling, circling or kinked roots.

[VoodooChile]

A 6' Katsura tree in a three gallon rootmaker pot. Smaller and larger sizes are available. This plant should have been moved to a grow bag in the field, or planted in the landscape last year.

Timing is crucial with the Whitcomb system, and transplanting/harvesting plants too late will result in many of the same problems of traditional b+b.

[phototropic1]

I've had great success with planting trees that were grown in Rootmaker bags. The first time I received a shipment of Nuttall Oaks, I was quite alarmed. The trees were 2.5" caliper, yet the rootballs were merely 18" wide by 15" deep. I thought "No way do these trees have a chance!" Because of the small rootball size, they were a snap to place. And I had no trouble removing the grow bags. After we had the tree placed, we simply cut four or five vertical slits starting at the top and ripped down. It was not much harder than removing a pot with one small root growing through a drain hole. And all of these trees have performed extremely well. They have required little supplemental water and have grown considerably. I would not hesitate to purchase bag grown trees again.
Oh, and like VoodoChile said, check out Carl Whitcomb and his Rootmaker system. It is well explained on http://www.rootmaker.com/whitsys.php