Will this Kill My Cedar?

[dtkabardin]

Got into bonsai last year. This was my first tree, a blue atlas cedar I collected from someone’s yard who posted it for free on Facebook marketplace. I collected it in July 2024, chopped half the tree off so I could get it home, and planted it in this tall pot with a mix of standard garden soil and pumice. I didn’t do any root work, just whatever roots the shovel sliced through when I was digging it.
Having researched bonsai more, I wished I had gotten the tree into a shallower and wider container back then. I’d like to do that this upcoming spring.
My question is, am I taking a huge risk if I do a repot again and do root work this upcoming spring 2025? Should I let the tree gain strength this year and try in 2026? I’m fine with taking a risk, just as long as the odds are in my favor. Here is the tree. I live in Sacramento, California.
Any comments/thoughts are appreciated!

 

[n8]

You collected and chopped this tree during the peak of our summer heat. It is likely suffering and relieved to have made it through October. If you see it push new growth in spring 2026, you lucked out.

I would not recommend any root reduction for a few years and if it responds with 2025 spring growth, I'd leave it alone. If anything, you may want to up pot it into a 5-10 gallon nursery container to let is regain some vigor before eventually doing root reduction for a shallower training pot in 3-5 years.

 

[Deep Sea Diver]

Still looks alive at this point.

Concur with @n8 Up pot the tree in the same media with larger container and let iit run. If it’s healthy all year, discrete pruning in fall ‘25 is ok. Would work on ramification the next year ‘26, then consider beginning repotting and changing out the outer media to bonsai media suitable for your area in ‘27 upon repot if all systems are go.

Cheers
DSD sends

 

[dtkabardin]

Thank you both, I’ll be holding off any root work for a while. Should I up-pot into a larger container in the spring time? I’m a little unsure of when to do it, as bonsai mirai mentions a 7 day window to repot blue atlas cedar, and I’m unsure of how I know I’m in that 7 day window. Or is up-potting not as invasive and can be done anytime since there’s no root damage?

 

[Shibui]

One of our very experienced growers here recommends mid summer as the best time to repot cedrus so maybe that's why it looks good. Not going straight to a shallow pot may also have helped IMHO. Bonsai is not a sprint. Need to work on timeframes of years rather than months so smaller steps aver time rather than huge leaps to the finish post. Plenty of time to reduce the roots when the tree is ready.
Having said that, Cedrus tend to take more time to grow new roots than many other species. I never count a cedrus repot as successful until the following summer so I'd agree with letting it go another year before further root works.
Up potting is safe any time of year because there's no root cutting involved. I'm not sure that I would up pot this one just now as the roots will not have a good hold of the soil yet so it's likely you'll end up with a bare root tree which is probably not the best option at this stage. The tree appears happy and healthy in the current pot so I'd be leaving well enough alone until there's some problem.

 

[rockm]

I would quit messing with it. It’s had quite a time for the last six months. Keep pushing it and it willl suffer from a cumulated damage. (and up potting is another push as it can disturb whatever new roots have developed. Moving the tree from one pot to another shuts the root mass and can damage brittle new roots)

 

[Deep Sea Diver]

Up potting is also called slip potting. This means one merely slips the entire rootball and media into another container and fill it with similar media. Little to no root disturbance if done properly.

The cues for repotting Ryan Neil gives for the Blue Atlas Cedar 7 day window are similar to most elongating species. Repot when the buds are open and actively start to push. At this time root reduction can occur. That would put the tree into mid May 25 in our area. In Sacramento, these cues will occur much earlier.

Ryan’s BAC page is here.

If the tree is doing fine right now, waiting until ‘26 is certainly a really good option. In that case one would go right into a flatter, yet deeper, training pot, perhaps an Anderson Flat.

One additional item would be to strongly consider shade cloth protection if you haven’t already… as BAC are known to struggle with high temperatures, especially when in pots.

Cheers
DSD sends

 

[rockm]

If you have a root mass that is tight and established and solid, moving it to a larger pot is no problem. BUT if you have recently-collected and in a pot less than a year, upotting will likely result inadvertent barerooting and subsequent damage to the root mass particularly new brittle roots. This is doubly true if you’ve never collected a tree or up potted a tree. Just sayin

 

[WNC Bonsai]

I slip potted one of mine in Oct. 2023 and it sulked most of 2024. While they are growing new roots they tend to ignore their above ground biomass and just sit there. Once the roots become well established they can be pretty strong growers. It’s always a good idea to take a watch and see approach with a new species before trying to push it.

 

[dtkabardin]

Great info, thank you guys! I’ll just be watering and fertilizing for 2025, and hoping it pulls through.