Advice on dwarf picea abies repot

[Lazylightningny]

I purchased a dwarf Norwegian spruce at a big box store earlier this year and slip potted it into my grow garden. It has thick, white, fleshy feeder roots. Last year I bought a bird's nest spruce with similar roots, and promptly killed it after root pruning and repotting, so I'd like to do a better job next spring when it comes time to pull it out of the garden and into some bonsai soil.

These thick feeder roots seem to populate mostly at the bottom of the root ball. I'm afraid that any root pruning will degrade the tree's abillity to take up water. Any advice on how to root prune them?

Also, I was thinking of doing some top pruning this winter.

 

[Japonicus]

I purchased a dwarf Norwegian spruce at a big box store earlier this year and slip potted it into my grow garden. It has thick, white, fleshy feeder roots. Last year I bought a bird's nest spruce with similar roots, and promptly killed it after root pruning and repotting, so I'd like to do a better job next spring when it comes time to pull it out of the garden and into some bonsai soil.

These thick feeder roots seem to populate mostly at the bottom of the root ball. I'm afraid that any root pruning will degrade the tree's abillity to take up water. Any advice on how to root prune them?

Also, I was thinking of doing some top pruning this winter.

@Lazylightningny 4 yrs later...and no replies, starting to think I should return
the one I just purchased from Lowes, picea Abies Little Gem. Very dense very slow grower.

Has yours survied?

What time of year did you repot the Birds Nest that promptly died?

 

[Lazylightningny]

That one bit the dust, but I have two more that are doing well. I'm using @Osoyoung method of bare rooting in August with no foliage removed and placed back into the sun. Spruce are definitely tricky. I'm still getting the timing down. But they look so awesome when trained.

 

[0soyoung]

I haven't played with these in nursery dirt. So, given your experience, I suggest you HBR to get it out of the nursery soil and only prune roots that are excessively long. Once out of the nursery dirt, I am sure you can do the '0soyoung method'.

I dug a big birds nest out of my mother-in-law's garden about this time 3 years ago (2015). It was a one-gallon nursery plant that had been in her garden for almost exactly 10 years. It was in sandy loam, so (IIRC) I simply shook out the dirt and only cut off two very long roots. I potted it in MVP and then did a full bare root repot on 22 Feb 2016 with only modest root pruning.



After a preliminary styling and trimming back to buds on 29 Sep 2016, it looked somewhat sparce (an 18 in-sq tile)



It filled in nicely the next spring, looking like this on 7 June 2017



I think 'nidiformis' is worth your while and worth doing whatever it takes to get thriving in a bonsai pot of yours. You can get bonsai material like this in just 10 years from nursery stock (note that is an 18 inch floor tile under the pot in the second pic) - they actually look quite nice as a landscape planting (of course, you can buy as many others as you would like for immediate gratification - probably lots of fun as a small bonsai too).


... end of thread bomb

 

[Japonicus]

Nice nest there 0soyoung. I sent you a message to avoid blowing out Steves thread here.
So you're saying you worked the roots late Summer then the following Winter went full blown BR?
Why not just BR at one setting in the Winter? I'm sure it has to do with the loam/sand soil
and the fact it was collected, but to not wait a couple years after that...just had to ask

 

[0soyoung]

Nice nest there 0soyoung. I sent you a message to avoid blowing out Steves thread here.
So you're saying you worked the roots late Summer then the following Winter went full blown BR?
Why not just BR at one setting in the Winter? I'm sure it has to do with the loam/sand soil
and the fact it was collected, but to not wait a couple years after that...just had to ask

I may have dug it about this time in 2014 - I didn't take any pix and cannot yet find any records. In many respects 2014 would make better sense than 2015.

But, yes, FBR the spring is because it was in substrate with very little dirt/muck to remove (I only wanted to check root health and to reposition it in the pot). Turface MVP (that I use) will just fall off the roots when dampened. If one conservatively root prunes, conifers can be repotted twice a calendar year in my climate, once in Aug/Sep and again the following spring. The season's new foliage is high powered, making the most auxin and carbohydrate that it ever will (i.e., productivity declines with age), IOW, I do not reduce the new foliage when doing this.

However, I hope that seeing the root/shoot ratio illustrated in my first pic is helpful, @Lazylightningny, I've tried to think of ways to prescribe what 'repotting' means in a variety of circumstances and when it comes to getting plants out of nursery pot soil, it seems impossible. I tend to buy inexpensive garden center stuff and forge ahead with FBR either in the spring or Aug/Sep. If it died, it died. I would get another and, instead HBR it next time.

I just think one must keep trying until success is achieved. And then after a train of successes, one will inevitably become more aggressive and will thereby develop a keen sense of just what they can do. Life is easy once they are in substrate and it gets easier yet as the root pad develops, in my experience. So, spend as little as you can, but get more and keep trying until you succeed. Then go for something nice, if you don't already have it.

Practice, practice, practice.