Over sizing grow bags in ground growing

[The Warm Canuck]

Instead of the standard method of up sizing grow pots as a tree grows, I'm wondering if this is still required when growing in the ground with a bag? (This pertains to early development, when trying to maximize initial trunk girth, growing in the same organic substrate, in the bag and in a raised bed).

Why the bag and not just in the ground? Because it allows for easy removal for root work and the ability to rotate the tree's yearly. Furthermore, I can remove my less cold hardy species and put them in my unheated garage in the winter, with little disturbance to the roots.

 

[Gabler]

Is there any advantage to actually burying the bags instead of just setting them on the ground?

 

[The Warm Canuck]

Is there any advantage to actually burying the bags instead of just setting them on the ground?

That's kind of the question. My thinking is that a tree can be over potted in a bag in the ground, due to the moister exchange allowed by the bags material, and get the benefit of rapid growth that the ground provides, but at the same time, allows the advantages of container growing, (easy removal for root work, rotation etc).

I think if just growing in a bag on the ground would require the same traditional up-potting methods to be followed.

Thoughts?

 

[Wires_Guy_wires]

I think most bags in the ground will get absolutely destroyed by roots once they escape.
The bags are meant for air pruning, and when that doesn't happen.. It's the same as a burlap: roots will punch through it and it will be just like a field grown tree except now you'll have to peel off layers of fabric.
I've seen it happen with those seedling pouches, and I have no reason to believe that anything larger would act differently.

But I have no experience with burying grow bags myself. So take this with a grain of salt or two.

 

[Maiden69]

Is there any advantage to actually burying the bags instead of just setting them on the ground?

It depends on the kind of soil you have. If your soil drains as fast as the bag, the advantage is holding moisture in the bag. If the soil is clay and it doesn't drain as fast you are just asking for trouble. As it will be basically a pool for the roots.

 

[Maiden69]

I think most bags in the ground will get absolutely destroyed by roots once they escape.
The bags are meant for air pruning, and when that doesn't happen.. It's the same as a burlap: roots will punch through it and it will be just like a field grown tree except now you'll have to peel off layers of fabric.

Not all bags are created equal... I just pulled my Chinese Pistache, Seiju elm and trident that were in my grow bed 2 years and there were very minimal roots escaping. All my BCs are in bags inside water and there are a few roots that escape, in a growing season they have not gotten any thicker than 1/4". Also, the bags are supposed to be use for no more than 3 years in the ground, that was Telperions mistake for allowing them to be in for 10+ years. At that time, yeah the bag would disintegrate allowing all the roots to escape.

Root pouch brand grey and black bags are designed to be IN GROUND and they do not air prune.

Cheap bags... I can't say anything about them. Any fabric will air prune.

 

[The Warm Canuck]

I think most bags in the ground will get absolutely destroyed by roots once they escape.
The bags are meant for air pruning, and when that doesn't happen.. It's the same as a burlap: roots will punch through it and it will be just like a field grown tree except now you'll have to peel off layers of fabric.
I've seen it happen with those seedling pouches, and I have no reason to believe that anything larger would act differently.

But I have no experience with burying grow bags myself. So take this with a grain of salt or two.

This isn't the case with bags that are designed to be planted in the ground. The same effect happens with air pruning, that the roots stop at the wall. (some small ones may grow through, but it's not an issue to remove them).

It depends on the kind of soil you have. If your soil drains as fast as the bag, the advantage is holding moisture in the bag. If the soil is clay and it doesn't drain as fast you are just asking for trouble. As it will be basically a pool for the roots.

I have the same well draining soil, in the bag and outside the bag.

 

[JEads]

The major advantage of a grow bag in the ground is the transfer of water and nutrient between the bagged tree and the surrounding soil. The pores of the bag are large enough to let fine feeder roots through, but not larger ones, so once the feeder roots grow into the surrounding soil, watering and nutrient distribution gets much easier.
You can have a bagged tree above the ground, but you will end up needing to water it much more than a normal potted tree. The exchange of moisture out of the bag can be intense, so I only recommend doing that with trees that like it drier

 

[JEads]

Not all bags are created equal... I just pulled my Chinese Pistache, Seiju elm and trident that were in my grow bed 2 years and there were very minimal roots escaping. All my BCs are in bags inside water and there are a few roots that escape, in a growing season they have not gotten any thicker than 1/4". Also, the bags are supposed to be use for no more than 3 years in the ground, that was Telperions mistake for allowing them to be in for 10+ years. At that time, yeah the bag would disintegrate allowing all the roots to escape.

Many of the trees that Telperion planted in the ground and left for 10+years still had their bags intact and were fairly easy to remove as one piece. Tridents and Scots pines easily could exploit a small hole or seam and get a huge root out, which made digging them almost not worth the time. But, I would not recommend leaving trees in the ground that long.

 

[JEads]

Instead of the standard method of up sizing grow pots as a tree grows, I'm wondering if this is still required when growing in the ground with a bag? (This pertains to early development, when trying to maximize initial trunk girth, growing in the same organic substrate, in the bag and in a raised bed).

I tend to plant seedlings in bags that are much larger than an equivalent plastic pot. I would never put a pencil sized maple in a 2 gallon plastic pot above ground, but I would not hesitate to do that for a bagged tree that is going into the ground.

 

[Maiden69]

Many of the trees that Telperion planted in the ground and left for 10+years still had their bags intact

That was not Ryan's opinion on the trees he bought from and was able to rescue during the fire. He stated that while there were nice roots close to the trunks, almost all the bags bottom area was disintegrated and roots were definitely growing out the bottom.

The best bags on the market now are the Root Pouch brand and the Root Makers, Root Pouch advertise 4-5 Years In-Ground, 7-8 Years Above Ground for their black line. 3-4 Years In-Ground, 5-6 Years Above Ground for the grey which are the ones readily available in the US. Black are harder to find. But I noticed that depending on the tree, 2 years is the max I would leave them in any bag unless you upsize a lot. Even my small JBP filled the 1 gal bag in less than a full season. I'm working the roots on all my deciduous this year, 2 - 3 years for all of them and I can tell you that the bags feel solid with roots. The liquidambar O. lost percolation and I had to poke holes last month so ensure water gets to the center of the root ball.

 

[pandacular]

Root pouch brand grey and black bags are designed to be IN GROUND and they do not air prune.

This part is interesting to me. You seem to use the black bags; do you not get air-pruning results with those in your bark grow beds? Or do you just mean when planted in the ground they do not air-prune? They advertise the grey bags fairly explicitly as promoting air-pruning.
Asking as I'm still trying to figure out which line to get for this coming spring for a bag-in-pumice grow setup.

 

[Maiden69]

This part is interesting to me. You seem to use the black bags; do you not get air-pruning results with those in your bark grow beds?

They do not air prune, they prune by entrapment. in or above ground. Cheap bags rely on air pruning, if you place them in the ground the roots will grow through the fabric until they either get strangled or destroy the bag. I use the grey line.

Root Pouch Products — Root Pouch

Different fabric blends for different styles of growing.

www.rootpouch.com

 

[Tieball]

I just grow the trees in the ground, on top of a large floor tile. No bags needed. I have a sand-based soil, no clay. When I want to dig the tree up I just run a reciprocating saw around the tile edge and lift it out. Then I prune the roots as desired for a box or to return to the ground. The roots grow just fine and easily lifted.

 

[JEads]

That was not Ryan's opinion on the trees he bought from and was able to rescue during the fire. He stated that while there were nice roots close to the trunks, almost all the bags bottom area was disintegrated and roots were definitely growing out the bottom.

I obviously cannot speak to Ryan's experience, but the 100 Telperion trees that I personally dug from the grounds of Telperion while some of their comrads were still smoldering were extracted with a shovel and their bags were 95% intact. Some had a few larger (sharpie) escaped roots, but most of the roots remained in the bag. The tridents were left for Randy to dig with an excavator and the Scots pines were too far gone.
I would never recommend leaving a tree in a bag in the ground for more than 3 years since the ground accelerates potential problems so quickly.

 

[The Warm Canuck]

I tend to plant seedlings in bags that are much larger than an equivalent plastic pot. I would never put a pencil sized maple in a 2 gallon plastic pot above ground, but I would not hesitate to do that for a bagged tree that is going into the ground.

I love it, 14 replies and only one person answers the question of the post!

 

[JEads]

I love it, 14 replies and only one person answers the question of the post!

Thats B-nut for ya!

 

[Millard B.]

Let me add my 2 cents worth to the mix, I bought some 15 and 25 gallon soft plastic grow bags from a friend who runs a huge nursery. I planted Bald cypress and Florida Silver Palms in them, they all grew fine. When I dug them out of the ground the Silver Palms grew their roots through the soft plastic like it wasn't even there, the Bald Cypress had roots resembling a ball of twine. I threw the grow bags away- too much trouble, not what I expected. Now for growing out special trees I use hard sided Accelerator Pots, they have 10,000 small holes that root prune the tiny roots and the larger sizes have fork lift spaces on the bottoms. The Accelerator pots can be moved and turned easily and can be used a second, third .... time. I now put all my first year collected BC in recovery ponds- 2"x8"x14' long pt frames lined with two layers of heavy plastic sheeting and I add minnows to eat the mosquito larvae. I also use the field grown tile method for my JBPs, get the trunks wired then place them on a 24"x24" dumpster dove tile, works good. don't waste your time or effort on grow bags not to mention your spine lifting a 25 gallon grow bag out of a hole. Good Luck!

 

[Maiden69]

don't waste your time or effort on grow bags not to mention your spine lifting a 25 gallon grow bag out of a hole. Good Luck!

25 gal? For bonsai? The largest one I have used so far is a 7 gal for a collected BC. Unless you are growing monster BC or bonsai I think nothing bigger than a 5 gal should be enough. Also, I suggest either folding it to half the height or cutting it. That way it would be easier to transition into a pot, vs having to chop the root ball several times in order to move the tree into a pot.

Results vary, cheap bags give you subpar results, messy roots. Root Pouch brand accomplish the same as the air pruning pots, without having to over water the tree because it is sitting above ground. BC was in a 2 gal pouch, the kabudachi was in a 1 gal.

Small 3 year old seedling BC, 1 year in the pouch. After teasing the outside of the root ball.


2 year old JBP kabudachi from @cmeg1 seedlings. 2 years in the pouch. Straight out of the pouch, not touching the roots.