I have a ton of nursery stock overwintering right now; what next?

[August]

Hey folks!
This last summer was my first year in this side of horticulture and I got some extreme beginner's luck in the form of: a ton of free nursery stock to work with. I started a seasonal position at a garden center in the Spring and was hired on for full time in the Fall, and thus was around for the annual "culling" of inventory. I think I have 7 or 8 various shrubs and trees in 3 gallon pots from that alone. Also dug up some elms at my property...

That is all to say, that I have probably 15+ pieces of nursery / field stock to work on next year. They're untouched right now, wintering over on my porch (looking good for my first winter too). Some part of me has been assuming that the logical next step would be to repot them in the spring and I've found myself questioning that lately. Surely it would be hasty to repot all of it (especially as it would be my first deciduous repot). So my question to the experienced masses of BNut, is: if you had this much untouched material, what would you be doing with it for it's first year with you?

I do plan on repotting some of them, many are rootbound, or in very poor soil. But I am left with a bit of decision fatigue, if that makes sense.

If the context informs your advice, here's some of the species: Korean Lilac, Rhus (aromatica?), Holly, Viburnum, Japanese Maple (of course), Aronia, Elms (either U. americana or U. pumila)

 

[caffeinated]

Generally speaking, starting with repots is a good choice. You'll start sorting out the roots, seeing what you have to work with, or not, helping you decide on a front or whether an air layer is in order, and beginning the process of getting good roots into a more small pot friendly state, if not just a healthier state.

 

[August]

@caffeinated that makes sense and is in line with my own understanding I suppose I worry about killing them with my inexperience. I understand a spring repot and the nuances but haven't ever done one. Knowing and doing... World's apart. Then again, I was panicking all summer about winter protection, and have had very few issues seemingly. Worry I will, though

 

[andrewiles]

If I were in your shoes and the goal was to use this material to learn, I would split them into 3 groups: repot some now, wire some now and leave some for future spring work.

As @caffeinated mentioned repotting is a good first step. In your Colorado climate it may be a bit early for that though. Unless you can protect from your rather variable weather. But regardless of when it happens, repotting is a key step to figuring out the work that needs to be done with the roots. When you repot, don't necessarily jump right into a small container. Much better to choose a larger container and give yourself time to work on the top as well. Repotting also gives you a chance to choose your soil mix and learn how it works in your climate. That can be an important economic decision. My approach has been to learn how to use locally cheap components, and to do that from the beginning of my learning process. Better to kill a small nursery tree than something important.

Wiring some trees now, or parts of them, will help you learn how they repond. How thick can be the branches be and still allow movement? How long do they take to set and bite in this spring? Knowing that now will help you down the road when you don't want to be experimenting on a tree or branch that you've already invested a lot in.

And leaving some for work this spring is a good idea as well. For example, those japanese maples are likely grafted, if they are cultivars, and a good first step there is to learn how to air layer at the base, or on individual branches, to get better trees. Those layers should be done in the spring on trees that have not just been wired or repotted, hence the leave-them-alone part.

 

[August]

@andrewiles Heard. I was planning on attempting my first air layer with the JM. Ugly ugly graft and kind of a stick.

How hard are the rules for doing one thing at a time, in your opinion? If I repot should I not touch them besides water and fertilizer until next year?

 

[andrewiles]

Unfortunately the answers are always "it depends". I have a young nursery dawn redwood that I repotted, severely root pruned, wired, severely top pruned, and then air layered all in 6 months time. Those trees are just crazy rugged. On the flip side, I have an Antarctic beech that will threaten to die on me if I look at it the wrong way.

If you don't mind the potential of losing some nursery material but learning along the way, go ahead and try some combined repotting and wiring. Or some wiring and air layering. I'd rather learn quickly what I can do with something than tiptoe around it for years.

I will say that you should almost always avoid repotting + a significant air layer in the same year, since air layers will directly tax that weakened root system.

 

[Shibui]

There are many ways to approach developing bonsai. Using your trees to try different approaches makes lots of sense if you are unsure.

I suppose I worry about killing them with my inexperience. I understand a spring repot and the nuances but haven't ever done one.

You need to start somewhere. Not doing repots will leave you still worried and unsure. My advice is to bite the bullet and get on with it. The sooner you see success the sooner you'll be able to relax and enjoy developing trees for bonsai.
So far we have not talked specific species, just deciduous has been mentioned. I've found that most deciduous are VERY tolerant of root pruning. Way more than any cautious beginner expects so I think your worries are natural but unjustified.
Let's see the list and see if we can put them into categories on how they are likely to respond which may guide you and/or alleviate some of the apprehension.

 

[dbonsaiw]

Without seeing the trees, I'd probably go in two directions - (i) get the tree growing as bonsai - repot, root prune, prune back branches and get into better soil. Nursery stock is grown as landscape trees and there is a bit of work to do in the beginning to get the nursery stock into bonsai mode. I also haven't been so great in choosing material, so I end up realizing that I need to prune back the tree quite a bit to get to the part of the trunk I want to actually develop further; and (ii) airlayer - if there are portions of the nursery stock that look like they can become bonsai themselves, I'd hold off on the repot and airlayer those portions off.

 

[August]

If the context informs your advice, here's some of the species: Korean Lilac, Rhus (aromatica?), Holly, Viburnum, Japanese Maple (of course), Aronia, Elms (either U. americana or U. pumila)

@Shibui here's most of the species!

Thanks everyone for the great advice. I think my takeaway so far has been that I'm stressing like I always do and I'm bound to have a fun season. It's great to have the experience to call on, though, I really appreciate it!

 

[Colorado]

I agree with the above - I usually work on the roots first with nursery stock.

If you are stressed about repotting technique, feel free to bring a couple over to my garden and we can do the first couple together if you’d like. Although I am sure you will do just great!

 

[August]

@Colorado thanks TJ, it's a date. I was already looking forward to following your footsteps to navigate the already stressfully CO spring / learn when the best time to repot is here. Hopefully our last frost will be before June this year

 

[Frozentreehugger]

There is good advice here . But step one is not repotting all the trees into bonsai soil . And or bonsai appropriate pots . Step one is a formative plan on What you want each tree to be . Then you can make decisions . On how best to create . By all means repot some of the trees into bonsai soil . And begin the training process . Generally dealing with nursery stock involves . Trimming downward roots . And spreading the roots out in a shallow container to develop a nebari . The trees are young and will respond well . Often newbies trim and start to develop the branches and top . When what they should do is just let it grow to develop a trunk . Again what’s the plan . Some trees can start development into small bonsai . At a very early age . Others need more time . There is a common misconception that everything must be potted into bonsai soil as soon as possible . There is nothing wrong with leaving some trees in nursery cans and soil . If it was so bad then why do nurseries use it so successfully . I am not saying there is no advantage to bonsai soil . Just that there is advantages to leaving a young maybe not supper healthy tree . In the container and soil it’s in . Get used to its care Allow the tree to get used to the climate in your yard . Learn how to keep it alive get it thriving .learn. Some trees may be better planted in the ground to develop for a few years . Remember if you leave them in nursery soil . Be careful you don’t overwater . One must consider the reasons . Nurseries use the soil they do . One is less watering labour required . Hope this helps . Do not take away that I am discouraging you from repotting . Into bonsai soil by all means . Learning to repot and correct watering for that substrate is necessary learning curve . But ask yourself if you repot into bonsai soil trim all the roots train the top and all the trees die . Besides discouraging yourself from practicing bonsai . What gave you learned .

 

[WNC Bonsai]

There are a lot of good YouTube videos showing how to work nursery stock from folks like Bjorn, Ryan Neil, Peter Chan and various others. I suggest taking a look at these just to see what is involved. Also my recommendation is to do the root reduction first, that way if it dies you haven’t put a lot of sweat equity and developed a personal attachment. The other way around you may chop, prune, and wire it to where you are happy with it then kill it the next year with a root reduction attempt.

 

[Frozentreehugger]

For what it’s worth @August . 15 nursery stock trees is not a large amount of trees . Once you get the bug in this hobby . And for good reason . Trees do not grow fast it’s nice to have more to keep you interested with things to do . I’m a huge believer that the best trees to learn bonsai with are the native trees where you live . They are adapted to your climate . And in general more forgiving of mistakes . And very easy to acquire. And if I lived at 5000 feet above sea level in the Rocky Mountains . In Denver I would be a pretty happy bonsai collector . .

 

[August]

@Frozentreehugger don't get me wrong, I love natives, but free shrubs are free shrubs I've figured from the start that they are worth practice and experience (perhaps through failure) if nothing else.

I definitely plan on adding to my collection this year, and the bug has made it's bite on me without a doubt. I think I have maybe 20 or 30 tropicals I've been practicing on over the winter

 

[Shibui]

Apologies @August I missed the list on first reading.
I am familiar with Japanese maples and elms but have not had first hand experience with the others.
Elms are extremely resilient. It would be quite hard to kill or damage elms by root pruning.
Japanese maples have good resilience and tolerate root pruning well, even better when young as yours are likely to be. I regularly chop JM roots back to short stubs on young JMs. Your root pruning is not likely to endanger those.
Hollies also appear to tolerate root pruning well though I have only worked with a few European hollies (Ilex aquifolium). I read posts about Yaupon holly being very easy to collect which means it has very good tolerance to root pruning so likely other species are also hardy.
Lots of different Viburnum sp but most I know have no problem with root pruning.

@Colorado offer to mentor is a great way to take the initial worry out of this process so great to see you intend to take up the offer.

 

[August]

Follow up question for anyone stopping by:

How do *you* decide when to move from field or peat soil to bonsai soil? Do you still use bonsai mixes (granular aggregate substrate) when you're moving into a large grow out pot or do you prefer "potting soil"? I can work out pros and cons for each but making the call of when  and why to use bonsai soil is still mysterious to me.

I figure: Spring, to a collection of trees in training, means a decision for each and every one of those trees (to repot or not, and then: what to pot into)

So, how do you folks usually make that call?

 

[JackHammer]

Follow up question for anyone stopping by:

How do *you* decide when to move from field or peat soil to bonsai soil? Do you still use bonsai mixes (granular aggregate substrate) when you're moving into a large grow out pot or do you prefer "potting soil"? I can work out pros and cons for each but making the call of when  and why to use bonsai soil is still mysterious to me.

I figure: Spring, to a collection of trees in training, means a decision for each and every one of those trees (to repot or not, and then: what to pot into)

So, how do you folks usually make that call?

Organic soil encourages growth. Inorganic soil inhibits growth. Most bonsai soil is predominately inorganic in order to accomplish slow growth on a developed tree in a small pot. Then you have the lifecycle in the middle where you have a mixture of the two. Pines need to be reported less frequently so it seems practitioners lean towards inorganic whenever possible. Pines also prefer drier environments so the inorganic soil becomes relevant sooner to assist with drainage. The inorganic soil has few nutrients so fertilizer is important. Some will also use charcoal to give the soil bacteria a place to live. Same thing with pine bark or coconut husks- you want a small amount of controlled organic activity to support growth while keeping the soil as inorganic as possible. The question I have is, in this scenario, we have soil that inhibits growth, and then we still want the trees to grow like crazy. It doesn't exactly make sense but the answer seems to be fertilizer- which may or may not contribute to pest or fungal issues. The cliche pastoral looking bonsai conifer may actually be a jacked up tree mutant living on a chemical cocktail.

Soil is one thing. Repotting time is different. The hot time is spring but this may be species specific.

I saw that you got a holly. I picked up one late summer last year and did a chop. This spring, I plan to split it from the multiple plants and let it grow in nursery pots with organic mushroom compost. The bark can be really amazing. You might want to do the same, or maybe just let it grow.

 

[Frozentreehugger]

Follow up question for anyone stopping by:

How do *you* decide when to move from field or peat soil to bonsai soil? Do you still use bonsai mixes (granular aggregate substrate) when you're moving into a large grow out pot or do you prefer "potting soil"? I can work out pros and cons for each but making the call of when  and why to use bonsai soil is still mysterious to me.

I figure: Spring, to a collection of trees in training, means a decision for each and every one of those trees (to repot or not, and then: what to pot into)

So, how do you folks usually make that call?

For myself . The idea started by the Japanese to use coarse fast draining substrate . Offers multiple advantages . For the tree . I don’t think we need to list them . Mainly because at best other soils can maybe equal sone of them . But can not equal it better all of them together . But like everything there is a price . The price we pay is first monetary . Most alternative soils are cheaper . To buy and or make . But mainly the price we pay is labour . To make mix sift the soil
And then more labour to water more frequently . Seems a pretty fair trade . When I repot I use coarse soil . I sometimes slow down the transition . From say a dug wild tree . And or not bare rooting some nursery trees . But I’m reporting into bonsai soil . My only use of regular potting soil . Is if I plant something in the ground . Or I delay removing a nursery tree . Until the season is correct or improve the vigor of the tree. Before repotting . But everything transitions . Into bonsai soil as soon as . Health possible for the tree

 

[brentwood]

This is an interesting couple of articles by a bonsai grower, might give you some thoughts while you're waiting for the weather to warm up a bit...

Evergreen Gardenworks Bonsai Beginners Page

I'm a big fan of nursery stock for starting into this hobby, practice material - fun to mess with an inexpensive juniper, turn it into something

Good luck!
B