Seedling transfer consensus

[Paul G]

What is the general practice among seed growers?

I have an assortment of seeds that have germinated in large tubs of decomposed pine bark. I plan to move them to 4" nursery pots once they are large enough. This is mostly a space saving measure as the tubs take up my whole driveway.

I will leave them in the 4" nursery pots for roughly 2 years, depending on their growth and health.

Would you leave them in decomposed pine bark while in the 4" pots, or use 1\16" particle size bonsai mix?

The species include:
-flowering crab
-Acer p
-Scots and mugo
-zelkova
-larch
-trident

Thanks in advance,
Paul

 

[Wires_Guy_wires]

For seedlings I stopped using bonsai mix for the following reasons:
- results varied per pot.
- huge taproots found their way to the bottom of the pot through the coarse substrate.

My approach for pines in general nowadays is:
- sow in organic soil
- sow in a shallow tray <1inch deep
- keep them there for 2 years
- chop off their heads in the first year.
- feed heavily

Results:
A root flare comparable to seedling cuttings
<1inch tall pines at the start of year 2. The bare "trunk" is shorter than my pinky nail. All the rest can bud because there were/are needles there.
Short internodes, loooong needles.
6 inch candles at the start of year 3. When in bonsai soil.


Those darker green ones have been treated like that.
These haven't been bent or shaped at all.

I found this approach less risky than seedling cuttings.

So to answer your question: I would keep the pines in organic soil if possible and adjust your watering habit to that soil.

 

[Paul G]

For seedlings I stopped using bonsai mix for the following reasons:
- results varied per pot.
- huge taproots found their way to the bottom of the pot through the coarse substrate.

My approach for pines in general nowadays is:
- sow in organic soil
- sow in a shallow tray <1inch deep
- keep them there for 2 years
- chop off their heads in the first year.
- feed heavily

Results:
A root flare comparable to seedling cuttings
<1inch tall pines at the start of year 2. The bare "trunk" is shorter than my pinky nail. All the rest can bud because there were/are needles there.
Short internodes, loooong needles.
6 inch candles at the start of year 3. When in bonsai soil.

View attachment 299286
Those darker green ones have been treated like that.
These haven't been bent or shaped at all.

I found this approach less risky than seedling cuttings.

So to answer your question: I would keep the pines in organic soil if possible and adjust your watering habit to that soil.

Thanks!!

 

[Shibui]

I almost always prick out seedlings when they are very small. The radical (tap root) can be safely pruned at that stage which will force good lateral roots much earlier.
I go straight to 4" squat pots with my normal bonsai mix but normal potting soil will probably be fine for trees in 4" grow pots. Definitely adjust watering to the soil you use.
Tridents may be ready for a new pot after a year but some of the others are a bit slower and may be Ok for 2 years in the same pot. Much depends whether you want maximum growth or better branching/shorter internodes for future development.
It is possible to leave seedlings in community pots or several years before transplant but growth is much slower when they are competing for resources.

 

[Paul G]

I almost always prick out seedlings when they are very small. The radical (tap root) can be safely pruned at that stage which will force good lateral roots much earlier.
I go straight to 4" squat pots with my normal bonsai mix but normal potting soil will probably be fine for trees in 4" grow pots. Definitely adjust watering to the soil you use.
Tridents may be ready for a new pot after a year but some of the others are a bit slower and may be Ok for 2 years in the same pot. Much depends whether you want maximum growth or better branching/shorter internodes for future development.
It is possible to leave seedlings in community pots or several years before transplant but growth is much slower when they are competing for resources.

Thanks for the feedback. I was wondering how early was too early to transfer.

 

[Paul G]

I almost always prick out seedlings when they are very small. The radical (tap root) can be safely pruned at that stage which will force good lateral roots much earlier.
I go straight to 4" squat pots with my normal bonsai mix but normal potting soil will probably be fine for trees in 4" grow pots. Definitely adjust watering to the soil you use.
Tridents may be ready for a new pot after a year but some of the others are a bit slower and may be Ok for 2 years in the same pot. Much depends whether you want maximum growth or better branching/shorter internodes for future development.
It is possible to leave seedlings in community pots or several years before transplant but growth is much slower when they are competing for resources.

Do you have a rule of thumb that you follow? I was going to wait until the first pair of leaves were full above the cotyledon...if I did an early transfer. Otherwise I was going to waif for hardening off. Also, any difference in your procedure for deciduous vs coniferous?

 

[Shibui]

Any time after the seedling is large enough to handle is fine. Usually that coincides with the first true leaves but that's not critical, just convenient for handling. I actually think the earlier the better for trimming the roots but it can be a bit frightening when you cut the one and only root on a seedling for the first time. It has now become routine for me.
The only conifers I grow here are pines and they are treated the same. You may have seen the seedling cutting technique for pines. I'm just cutting a little lower and they seem to respond faster and better. Sometimes I have left they a little longer and there are already very tiny lateral roots starting so I cut right below a convenient cluster of laterals but they still grow fine even when all root tips are removed.
You should note that one member tried following my recommendation with some bald cypress seedlings and they all died. Not sure whether that is the species or the handling or aftercare caused that result as I've only ever had one batch of BC seedlings a many years ago and forgotten what I did to those.

 

[sorce]

wait until the first pair of leaves were full above the cotyledon

The Cotyledon contains all the energy a tree needs to go from point a to point b.

Cut the roots at a.1 then by b you are already in control, and directing energy efficiently.

I did this with one of my JBP seeds and it worked.

IMO, there is much to be explored in this realm still. We should definitely be seeking new ideas here.

I would also consider using a proper root pruning container for the first year or 2.
This will build a "core" of roots that can always be cut back to safely. Yes, you may sacrifice a bit of growth, but that will get made up in every later year you don't have to cut all the roots off .

Species specific.

If it layers well.
Haphazard the roots and throw em in the ground.
Layer later.

IMO....

Organizing seedling roots will end up good 3/10times.
Layer roots will end up good 8/10 times.

This has nothing to do with man, only chance.

Sorce

 

[Paul G]

Any time after the seedling is large enough to handle is fine. Usually that coincides with the first true leaves but that's not critical, just convenient for handling. I actually think the earlier the better for trimming the roots but it can be a bit frightening when you cut the one and only root on a seedling for the first time. It has now become routine for me.
The only conifers I grow here are pines and they are treated the same. You may have seen the seedling cutting technique for pines. I'm just cutting a little lower and they seem to respond faster and better. Sometimes I have left they a little longer and there are already very tiny lateral roots starting so I cut right below a convenient cluster of laterals but they still grow fine even when all root tips are removed.
You should note that one member tried following my recommendation with some bald cypress seedlings and they all died. Not sure whether that is the species or the handling or aftercare caused that result as I've only ever had one batch of BC seedlings a many years ago and forgotten what I did to those.

Thanks again