Grow box size

[Hobbes]

I've been reading a lot about grow boxes lately but still haven't found any good recommendations on footprint. I also read Brent's article on pot size being no more than 2" wider than the root ball. But I figured if you're attaching your tree to a piece of wood to encourage horizontal root growth, the 2" rule wouldn't apply.

So how much larger than the root ball should your grow out box be? 6"? More? Thanks in advance.

 

[Vin]

You have two different issues in your question. 1) How much bigger than the root ball should a grow box be? 2) Encouraging horizontal root growth by attaching a wooden plate to the bottom of a tree (or at least that's what I think you mean).

Grow boxes encourage growth by providing good drainage and air flow to the roots (when the proper medium is used). I would say you need the box to be greater than 2" around the root mass for that to occur. Now if you attach a piece of wood or tile to the bottom of the tree it kind of messes up the drainage and air flow a bit. If you do that, I would say the box needs to be a minimum of 3 - 4 inches greater than the dimensions piece of wood or tile to get any benefit. Maybe others will offer more information as well.

 

[Diolated]

I have no scientific backing, only anecdotal experience re your question. My belief is that the grow box should be as small as it possibly can be and still fit your root structure inside. A whole lot of roots can grown in a tight little space, and a big box is difficult, if not impossible to move on your own when filled with a soil and a tree. I also have started install little cheap handles from the hardware store to help lift my grow boxes -- a small, but very helpful little addition.

 

[parhamr]

Variously, my guidance is: “as large as you can comfortably move” OR “no larger than what the tree can reasonably fill” OR “whatever the tree can use without suffering”

In practice, that tends to be 5–10 inches deep and 14–30 inches across for many medium-to-large trees.

 

[Hobbes]

Thanks everyone! Exactly what I wanted to know.

 

[Anthony]

I would ask what are you trying to do?

Trunk and root work better with tile and colander in the open ground and for us down here the first 6
branches.
Then an over sized bonsai pot for branchlets [ refinement stage ].

Additionally, for us, 6 inches internally is a health limit as soil to tree goes, in a non porous pot.

Plus for us at 1 inch trunk to 5 or 6 inch of height , 30 to 36 inches of height/or width [ trunk = side of bonsai pot ]
would be a bit too much to lift.
Good Day
Anthony

 

[Hobbes]

Looking to grow out trunk and nebari. This would be for plants that need winter protection and can't be planted in the ground. Thanks!

 

[Anthony]

Hmm, then what you need is information on the trees you want to grow and their response to being in a grow box.

On our side, there are just a few trees that respond to a grow box, which is why we stopped bothering with grow
boxes.
Those that did respond to branch extensions, did so in small shallow bonsai pots.

We use grow troughs, roughly 8' long x 2 ' wide by 2.5' deep.
They are basically brick /mortar/plastered, set on concrete.
They came with the house.

It is important to get an idea of what you can achieve in say a year or two.

So see if someone who has effectively used grow boxes will speak out, and can tell you what to expect.
List trees/shrubs and ask for results.
Good Luck.
Anthony

****
Pity you couldn't just plant in Florida in the ground, unless they are true tropicals - limit 55 deg.F
as the cold goes.

 

[Hobbes]

Thanks. This will be in Wisconsin. From what I've been reading, people don't have problems with grow boxes in the states.

 

[augustine]

On evergreengardenworks.com there is a section with articles. One of these articles is about overpotting, check it out.

 

[Hobbes]

On evergreengardenworks.com there is a section with articles. One of these articles is about overpotting, check it out.

Already have, thanks.

 

[Vin]

There was a question about the bottoms of the Grow Boxes I posted @vicn As you can see in the image below, I have a staple between each slat to hold the mesh tight. I haven't experienced any sagging of the mesh but the staple only lasts a season or two. I guess I could use something galvanized or stainless but it's no big deal to put another staple in if need be. I like the drainage and air flow this design provides.

 

[Hobbes]

Very nice. What kind of mesh do you use Vin?

 

[Vin]

Very nice. What kind of mesh do you use Vin?

Plastic canvas from Hobby Lobby. It comes in different mesh counts and it's really really cheap. I use it to cover the drain holes on pots as well.

 

[Hobbes]

Awesome. I know exactly what you're talking about. I use the same stuff, although clear, for some different DIY things. Thanks!

 

[JoeR]

Plastic canvas from Hobby Lobby. It comes in different mesh counts and it's really really cheap. I use it to cover the drain holes on pots as well.

It can also come in larger sizes, like 2'×3' sheets. Its what I use, and it holds up really well.

 

[Hobbes]

Joe, where do you get bigger sheets from?

 

[JoeR]

Joe, where do you get bigger sheets from?

Same place, Hobby Lobby. Michaels doesnt carry it at all, at least not here.

They dont always have it in stock

 

[Grant Hamby]

I have some rooted cutting stock (arakawa maple) that I'm trying to beef up a bit and I'd like to go the pond basket/anderson flat route. My question is: Should I put the cutting straight into the anderson or put it in the pond basket until it outgrows it? If I'm planning on doing annual root work, it seems like I should start smaller and work up to the anderson later, but I figured I better ask in case that's not a good idea.

 

[aml1014]

I have some rooted cutting stock (arakawa maple) that I'm trying to beef up a bit and I'd like to go the pond basket/anderson flat route. My question is: Should I put the cutting straight into the anderson or put it in the pond basket until it outgrows it? If I'm planning on doing annual root work, it seems like I should start smaller and work up to the anderson later, but I figured I better ask in case that's not a good idea.

I'll be starting to use the ebihara technique on tons of maples from 4inch pots to 7 gallon pots I've started from seed the last 2 years, they're gonna go straight into 15×15×4inch grow boxes next spring. When using bonsai soil, it's pretty difficult to overpot IMO.

Aaron