Ladder Leaf Cotoneaster nursery stock. Thoughts/advice on a root reduction/slip pot?

[SilverShoe99]

Sup nuts.

I've got a couple Ladder Leaf Cotoneasters that I picked up on a lark from a nursery a few months back. As I haven't yet got a plan for them, they've just been sitting over in the corner of the yard doing their thing. I've noticed that they haven't grown as vigorously as I'd have expected them to this spring, so I pulled them out of their nursery cans and found.....this.






This is just one of the two, but they both look the same - totally rootbound, major air pockets in the root ball, and slugs living in the air pockets.

Ideally, I'd like to reduce these rootballs and get these into some bonsai soil, but I'm inclined to think it's probably too late into spring to do that safely. Alternatively, I was wondering if I might be able to safely reduce the rootball by 1/3 to 1/2, tease out the outer circling roots, and slip pot it into a bonsai soil/training pot situation.

All advice is welcome. Thanks!

 

[SilverShoe99]

Alright, so we did some work on these two. The treatment for both was pretty much the same, so I only took photos of the work I did for one of them.

The intent was to only reduce the root balls by 1/2, but once I got in there....things escalated.

First I used a saw to cut off the bottom half of the root ball. Both were super root-bound in their nursery cans, and the rootball held together tight as I sawed through it. In the past when doing rootwork on nursery stock, sometimes the rootball will fall apart as soon as I start sawing through as the visible circling roots are all that the plant has got. Not so in this case - the middle of the rootball was full of downward growing, thick, lignified roots.


Next I did a bit of work raking the out- and under-sides of the rootball. You can see where I've pruned off some of the thicker, downward-growing roots.


Some more raking, some more reduction of the thick, downward growing roots and we're left with....not much.




Next getting the training pot ready. For this one I'm using a 6" terracotta pot into which I've drilled extra drainage holes.


Some vinyl pet screen to keep the soil in.


And voila, the 'finished' product. Once I got my hands dirty mixing substrate I stopped taking photos, but the trees are secured with wire threaded up through the drainage holes,and the substrate I used is DE/Perlite/Bark Fines in a roughly 2:1:2 mix.


Dappled shade for the next couple weeks as they recover, and then back into full sun come June.

 

[misfit11]

It's pretty late in the season to be doing aggressive root work, but they might be okay. The damage is done. I agree with putting them in the shade. Let us know how it works out for you.

 

[SilverShoe99]

Agreed 100%. If the roots hadn't been so bad I'd have left them. At this point, time will tell!

I'll be sure to post updates.

 

[AlainK]

Cotoneaster is a very resilient species, I think the chances it will survive are quite high if you take proper care of it.

 

[SilverShoe99]

Cotoneaster's reputation as being particularly robust factored into my decision to have at the roots so aggressively this late into the spring.

@AlainK, I haven't got much experience with cotoneasters. Beyond watering, no fertilizing, and keeping it in the shade for a few weeks, do you have any advice as to how I should care for them to maximize the chances of recovery?

 

[AlainK]

From my limited experience :

Some deciduous trees can recover from drought, when all the leaves are dry : maples, hornbeam, ash, etc. You think they're dead, but if you remove the dead leaves and water the the tree sparingly, there's a new flush of growth.

When cotoneaster leaves are dry, it's dead, definitely dead : I shouldn't have used the term "resilient", I meant they can stand major cuts, root pruning, etc. but they need a minimum of water and oxygen to the roots. When the leaves are dry, the roots are dead.

So far, so good with your tree. I wouldn't touch it for the moment, but the branches are very straighjt, so next spring, I would prune it very hard, without touching the roots.

But it's probably better to let it grow freely now...