When to move rooted cuttings out of the prop box?

[zeejet]

I've haphazardly rooted a number of cuttings in a propagation box starting in late spring after thinning some new growth on the mother trees and surprised to find that many of them have rooted (Japanese maple, trident maple, unknown prunus, Chinese elm, etc).

I used 3" pots in a Sterilite container for humidity - 1.6% IBA Hormex powder

I don't have much experience with cuttings but what do I do at this point? In my limited experience, a lot cuttings start to rot if kept in the humid environment too long - but I don't think summer is a great time to transplant to a larger container outside of the prop box.

 

[LuZiKui]

Are they all in their own pots or are they all in a connected tray? I think you're right, transplanting probably isn't the right move right now. If they are starting to root I think I'd get them out of the prop box and move them to a shady location and see how they respond. If they continue to grow I'd give them progressively more light through the end of the summer and plan on repotting in the spring.

 

[BrightsideB]

Probably just wait until it gets cooler. You are in a zone you don’t have to worry about winter but rather summer.

If you have a humidity dome than I’d remove if there are roots. The leaves have roots now so it isn’t needed.

 

[BrightsideB]

Probably wise to keep in the shade though until it isn’t scorching hot

 

[BrightsideB]

I hear jm is pretty hard to keep healthy there though

 

[zeejet]

I hear jm is pretty hard to keep healthy there though

Indeed - some varieties fair better than others (my Mikawa and Summer Gold are OK with very minor scorch but my red JM was completely scorched by mid-May).

 

[Wulfskaar]

I have a couple very young JM and an older JM shishigashira. I keep one JM and the shishigashira in dappled shade (mostly shade) and the other gets late morning sun. They seem to be doing ok so far with no leaf burn yet.

I expect the really bad leaf burn will happen in fall when we get the Santa Ana winds (dry, hot wind). It always happens right before they turn color, so my fall foliage on JM is very sucky.

 

[Shibui]

I pot up rooted cuttings whenever they need doing, regardless of time of year or weather. Younger roots seem to be able to cope with transplant much better than older trees so rooted cuttings transplant well.

 

[penumbra]

I pot up rooted cuttings whenever they need doing, regardless of time of year or weather. Younger roots seem to be able to cope with transplant much better than older trees so rooted cuttings transplant well.

I find this to be more true with seedlings than with cuttings on some plants, AP being one of them. This is just my experience.

 

[Attmos]

I have a few that rooted and I'm scared to death to do anything with them until they become more established.

I think "Whenever they need doing" is kind of a subjective topic.

 

[River's Edge]

I have a few that rooted and I'm scared to death to do anything with them until they become more established.

I think "Whenever they need doing" is kind of a subjective topic.

I use the following guideline. Wait for new growth to begin on the cutting. when there are two or three new sets of needles or leaves the roots should be good to transplant to individual setting. This is different for species. For example new shoots on juniper or cypress will be longer in my experience than deciduous trees. so two or three sets of leaves or two or three sets of needles. Maybe a two to three inch new shoot. Experience will guide you. Check one for root de elopement before committing to move them.

 

[SeanS]

If your propagation box is sealed (to increase humidity) don’t just remove the cuttings immediately and transplant. I usually lift one corner of the lid a cm or 2 and gradually increase the opening each week. You need to wean the cuttings off of the high humidity before moving them to the “outside world”.
Well that’s what’s worked for me, it may be overkill
Same with cuttings covered with a plastic bag. I’ll cut a small hole in the bag and gradually make it bigger over a few weeks.

 

[Attmos]

I use the following guideline. Wait for new growth to begin on the cutting. when there are two or three new sets of needles or leaves the roots should be good to transplant to individual setting. This is different for species. For example new shoots on juniper or cypress will be longer in my experience than deciduous trees. so two or three sets of leaves or two or three sets of needles. Maybe a two to three inch new shoot. Experience will guide you. Check one for root de elopement before committing to move them.

How do you go about checking one without disturbing or breaking the new little roots, if there are any?

 

[Attmos]

I use the following guideline. Wait for new growth to begin on the cutting. when there are two or three new sets of needles or leaves the roots should be good to transplant to individual setting. This is different for species. For example new shoots on juniper or cypress will be longer in my experience than deciduous trees. so two or three sets of leaves or two or three sets of needles. Maybe a two to three inch new shoot. Experience will guide you. Check one for root de elopement before committing to move them.

And.. Thank you for the advice.

 

[Attmos]

If your propagation box is sealed (to increase humidity) don’t just remove the cuttings immediately and transplant. I usually lift one corner of the lid a cm or 2 and gradually increase the opening each week. You need to wean the cuttings off of the high humidity before moving them to the “outside world”.
Well that’s what’s worked for me, it may be overkill
Same with cuttings covered with a plastic bag. I’ll cut a small hole in the bag and gradually make it bigger over a few weeks.

What I did to them would shock you.

 

[Shibui]

I think "Whenever they need doing" is kind of a subjective topic.

The point was that time of year is not a factor. It's the stage of growth that dictates time for potting up and @River's Edge has given some good visual cues to look for.
I usually wait for both new shoots and some roots peeking out of the drain holes at the bottom of your cutting pots. You can also carefully slide the soil ball out of the pot to check for roots. If you are careful enough you can also slide it right back in with very little disturbance if you find just a few roots instead of plenty.
One good thing is that there's not a definite window of time when potting up needs to be done. If you are a bit early some of the roots may break off but most of the cuttings will survive if you are gentle. Leaving them longer means the roots will be a bit tangled but they will still usually cope with the separation and transplant.
If you tip a pot out and find no roots just put the cuttings back in and leave until the roots do grow. A gentle check is not a death sentence.

The following pictures are of pine cuttings but might help show the root development part of cutting propagation.
Roots showing at the bottom of the pot.


Plenty of roots when slipped out of the pot.


Cuttings separated. The ones with roots are potted up, the ones with no roots are put back in cutting mix and returned to the propagating area. They may still produce roots.


This series are Chinese elms.
The top - not many new shoots up top.

But roots are showing out the bottom so I know at least some have produced roots.


Shake the cutting mix off the roots. For bonsai, spread the roots to give good future nebari.

 

[River's Edge]

How do you go about checking one without disturbing or breaking the new little roots, if there are any?

You don't. the only way you can check is check. I use the blunt end of a root rake or even a spoon to gently lift up from the bottom the soil mix and then pull the seedling gently out. if there is resistance I lift more from the bottom. At this stage losing a bit of root is not a problem. I use Anderson flats with plenty of seeds as the first step. It is important to transfer before the roots get too entertained. Not a problem fore those who use individual pots of some type for each deed.

 

[River's Edge]

For purposes of this thread it should be noted that cuttings tend to form thicker roots than seedlings. This changes the dynamic and process when dealing with transplants. The process also changes with the type of propagation equipment used and the degree of difficulty propagating the material. Checking and then placing scions back in the rooting media for further progress is not uncommon. Once one becomes familiar with a particular species it is easier to judge the stage of progress through the new growth pattern. For example; Prunus Mume cuttings will be well rooted when three sets of new leaves have been produced. This is not true for Trident maple cuttings. They produce new leaves with far fewer roots and thus patience is advised before disturbing.
I would be cautious about accepting guidelines if your methods and equipment varies. Take your time, observe and if in doubt wait!