Aeroponic mist cloner -- cutting freshness and root type

[Needaclone]

I know that a few folks on this forum have experimented with hydroponic and aeroponic cloning.

I've been following some ongoing threads and reading some past threads.
I've been thinking of putting together an aeroponic mist or fog cloner using an an ultrasonic fogger, following the basic approach that others on the various forums have been using lately...but a few questions/reservations are coming to mind.

First, many folks report results for using fresh cuttings. Does anyone know how well things are likely to work with dormant cuttings, perhaps that may have been stored in the fridge for weeks or months?

Second, it is said that "water roots" formed in water are not the same as roots formed in soil...not as strong and not adapted to the function of pulling water and nutrients from the soil. Are the roots formed in a mist/fog-type aeroponic cloner water roots? Or are they more similar to the roots we'd want to have for potting up immediately after rooting?

Any insights anyone can share would be appreciated.

Cheers,
Jim

[Rafaelissimmo]

Hey Jim

This is my second year doing aqua cloning, I do not use a fogger but an aquarium stone, Harvey may be using a fogger, don't remember what Sharon uses. NYC Fig (Danny) uses a stone, and Coop is also using this method.
As for the roots, I have pondered this since last year. I have uppotted this year 2 cuttings, one just tonite. I think the roots per se are not qualitatively different, it is just a question of transitioning their environment from water to media. Of course, you do not want to put them into too dense or wet of a mixture. I lost a lot of cuttings transitioning last year. I expect much better results this year. A heat mat helps for transitioning, as does a naturally warm environment. But I do not think the roots need any other special treatment. Only in the event that I saw a cutting failing on transition would I use a humidity chamber.
As for types of cuttings, I agree with others that green cuttings are not best for this option. But recently taken autumn cuttings and older cuttings have both worked well for me. Some varieties just take forever to start growing roots in water, no matter how long the cutting has sat in the fridge. Good luck.

[SharonC]

Hi Jim,

I'll let you know but some of my cuttings were from fridge and they are rooting. I'll be putting more in cloner this week from frigerator. I use a mister.

[AscPete]

Jim,

Aeroponic and Hydroponics (Bubble cloners) work better for green cuttings. In use they are set up with most of the cutting exposed to room air due to the leaves, not in the wet cloner. Green cuttings have an active vascular system that benefit from the very wet environment at the stems.

Dormant cuttings need to hydrate and callus before root formation. If they have been stored then they could be "pre-hydrated" (pre soaked for a few days) before starting the pre-rooting process, whether in a cloner or one of the many established methods.

The Fogger may work better for pre rooting especially when covered with a dome because it keeps the entire cutting in a moist environment (high ambient humidity). The entire cutting "hydrates" faster and the rooting process progresses faster especially if the ambient temperature is also above 72*F.

The exposed "air" roots that are formed are similar to those formed in soil not water. In soil there is a large volume of air surrounding the roots with intermittent moisture, similar to the aeroponics misters or foggers. The roots are initially weaker because they have not been exposed to the "resistance" of the soil.

IMO, since the cloners are used simply for pre-rooting, they aren't necessary if you are only doing a few dozen cuttings. setting up a seedling plug tray, a tall humidity dome, some Coir potting mix and a misting bottle would probably be faster and certainly cheaper.

[Needaclone]

Sharon -- I'm glad to hear that you had success with cuttings that had spent time in the fridge. I encourage you to keep us all updated on progress and overall results.

Pete -- I had hoped that the roots formed in a fogger or bubbler would, indeed, be more like the air roots that a cutting usually forms. It makes sense, but I hadn't read any scientific or anecdotal accounts to that effect. (Actually, I read an anecdotal statement that they were more like water roots -- which is the reason for my post ;-) Perhaps if the cuttings were completely submerged (e.g. as in a typical aquaponic setup) this might be the case. (But plants grown in that environment probably aren't intended for potting...)

I guess that when people say bubble/mist/fog cloners "work better" for green cuttings, it really means that green cuttings might see more accelerated results since the vascular system is still active and it is fresh.

Conversely, just because a cloner "works better" for green cuttings doesn't mean it doesn't work well for dormant cuttings -- true?

Pete -- you mention the use of cloners for "pre-rooting." Do you have any experience with leaving the cuttings in for longer periods of time. Some others have done this, reporting that the cuttings can grow strong, extensive roots while in the cloner. Actually, this is PERFECT for me. My track record shows that I never seem to get to remove the cuttings from the sphagnum moss shoebox when I should. The longer roots get entangled with the other cutting's roots and the sphag moss. I would welcome a setup that rewards me when I leave the cuttings in longer ;-)

I already have everything I need for an aeroponic misting cloner (minus a heater), but I'm hesitant to "pull the trigger" and risk my cuttings. I also have never rooted in coir (which I've read good things about), but I know I wanted to try something different than sphagnum moss.

Cheers,
Jim

[Rafaelissimmo]

Pete, thank you for pointing out about green cuttings and vascular systems. I have a question: I normally consider a "green" cutting to be a summer cutting. What about a dormant, but improperly lignified green cutting, that is then taken and stored in the fridge. And later rooted. Is that a "green" cutting with a more active vascular system, or is it considered closer to a regular dormant cutting?

[AscPete]

Jim,
The moisture and light requirements of green / actively growing / summer cuttings are quite different from dormant cuttings. Green cuttings need a wet environment and light, Dormant cuttings need a moist airy environment and no light to produce roots and start to grow.

The process of (hydro or aero) cloning is actually pre-rooting the cuttings before they are up potted. Ive left the cuttings in longer, but the there is no added gain. I have grown out fig cuttings in an hydroponic system with decent results. Normal container grown was easier and resulted in much better tasting figs. If you use an aeroponic system for rooting fig cuttings, the "cut just below the bottom node" still applies and the majority of the cutting should be suspended below the insert and well above the water, in the mist. It will hydrate the cutting and you will get root development on most of the material below the insert.

Direct planting in small of large containers has proven to be the simplest method of rooting cuttings. Soak for 2 - 3 days, seal the top end and plant in a moist pre-watered well aerated mix at ~75*F in a sealed container, in a dark space. check every 2 - 3 days.



Rafael,
A "green" cutting is an actively growing cutting with green leaves.
A green dormant cutting is still a dormant cutting regardless of its exterior color there is no active vascular system..

[rg]

Pete,

You mention above that "Normal container grown... resulted in much better tasting figs."

Is this true over the life of the tree or just a few seasons? When does the taste normalize?

Thanks.

Randy

[Needaclone]

Pete,
Yes, I had the same follow-up question/clarification as Randy. When I was referring to leaving the cuttings in the aeroponics setup longer, I didn't mean for an extended time until they were producing figs! I just just meant beyond the point where initials were growing. Perhaps to the point where the roots are multiple inches long and perhaps there are even a few leaves.
Jim

[AscPete]

Randy,
My comparison was between a hydroponically grown fig and the same cultivar grown in my standard potting mix....
The additional labor and expense involved in growing the hydroponic trees did not provide any measurable returns in better tasting figs or increased plant size.

Could you please clarify your question?


Jim,
Attached are the roots of a cutting at ~40 days in the Hydroponic Bubble Cloner. plain water was used to root the cutting, after rooting @ ~21 days the water was replaced with a dilute hydroponic grow nutrient solution mixed at 1/3 strength. Some of the the cuttings in the picture were started at a later date. Its been my experience that that the faster you get the cutting in a potting mix the faster growing and healthier your young tree.

[Needaclone]

Pete,
Has it been your experience that the roots in the bubble cloner were hardy and robust, especially in terms of "toughness"? When roots get that size in sphag moss, they tend to be brittle. Again, I'm wondering if one of the side benefits of leaving the cuttings in the cloner "too long" is that the roots toughen up a bit.
I agree there's no substitute for getting them potted up and letting them start to become trees. But when that doesn't happen as soon as it should (due to life circumstances), keeping them in the cloner seems like a pretty reasonable option!
Jim

[AscPete]

Jim,
IMO, The roots didn't develop properly in the cloner, although they looked healthy and the plants were growing well, they would have been twice the size in a potting mix. I've attached another picture of roots that developed with Long fibered sphagnum moss in a plastic bag in the dark @ ~4 weeks and they weren't fragile.

[rg]

Pete,

I think I understand what you meant now.... you actually grew a fig cutting hydroponically until it grew a fig? Then that fig didn't taste as good as a fig on a tree grown in your standard mix, right?

[AscPete]

Yes.

[SharonC]

I'll admit something. The cloner is my toy. It works no better right now that rooting in perlite in the dark. It does keep me from digging up my cuttings everyday to see what they are doing. I can peek in the cloner 3 times a day and it doesn't bother them at all. I think maybe I will add a view port to the next one. The one advantage it has over perlite is that if the leaves do start first they are green and nice rather than the pale things that rot in the perlite. I'm doing both right now. I suspect once Spring gets here I will be too busy to bother the cuttings much.

[Needaclone]

Sharon,
YES! Those are the kinds of things I'm trying to determine -- weighing the advantages against the disadvantages.
I have no doubt at all that there are optimal conditions for the cutting at each stage in the process of going from a stick of wood to a potted-up tree. And I have no doubt that there are optimal times at which a transition from one stage to another should occur (again, from the point of view of the cutting/tree.) But I, personally, have a definite problem in that doing what is optimal for the cutting never seems to synchronize with what's going on in my life. I just don't seem to get the time to do the things I need to do for the cuttings exactly when it would be best for the cuttings.
The two things that seem most appealing to me are
a) root growth - there is no significant downside to letting the roots grow longer and bigger (assuming you can get them out through the hole.) It may be better for the tree to get them potted up earlier, but it is not detrimental to leave them in longer (within reason).
b) leaf growth - Adding lights above the cloner (either before or after roots have formed) can promote better top growth (compared to the pale and rot-prone leaves you may get in perlite/moss, as Sharon observed.)
In this sense, the fog/mist cloner seems to be a more "forgiving" way to root cuttings. If I let something go a few days (or even weeks) longer than I should, there don't seem to be any horrible consequences...
JIm