Rooting High-Value Cuttings (Passive Aeroponics)

[ThaiFigs]

I have been looking for a low cost way to root high value cuttings in my climate, where the temps range from 80 to 90 degrees between night and day. Although I've sucessfully rooted in cups, I've also lost a lot of cuttings to mold that way due to our high temps. I've rooted in water, but changing water daily is a chore. I've rooted in NFT hydroponic systems, but setting that up for just a couple cuttings doesn't seem worthwhile. So I decided to try passive aeroponics. Passive because it uses no electricity. Aeroponics because it uses water in vapor form to keep things moist.

I wrapped the top of the stem with plastic wrap so I don't need to use a humidity cover.

I made a foam plug to hold the cutting in the bottle, and electrical tape to act as an additional moisture barrier. A wet paper towel provided the water vapor by evaporation.

3 weeks after starting the test, we have first roots.

Clearly all that figs require to begin rooting is an environment that provides adequate humidity and oxygen.

This cutting is now ready to be moved to a tree pot.I will use a 50/50 mix of coir and rice husk with bottom irrigation for that step.

[eboone]

Clearly all that figs require to begin rooting is an environment that provides adequate humidity and oxygen.

How do figs use oxygen?

[ThaiFigs]

Plant cells use oxygen for growth and cell division just like animal cells do. Without access to oxygen, roots will die. This is why plants can drown when overwatered. Only the leaves of plants can produce oxygen, and then only if they are getting sunshine. At night they too consume oxygen.

[AscPete]

Thanks for sharing the photo and info.
...


A similar bottle method was one of the first Green or Summer rooting methods that I tried my first year growing figs. It was posted by King Fig , Dan_LA at the fig forums.
http://figs4funforum.websitetoolbox....gs-201-5451326

[COGardener]

Ok.... that's pretty cool!!

I'm really glad you posted this, I will for sure be giving it a try.

[ThaiFigs]

Thanks for sharing the photo and info.
...



A similar bottle method was one of the first Green or Summer rooting methods that I tried my first year growing figs. It was posted by King Fig , Dan_LA at the fig forums.
http://figs4funforum.websitetoolbox....gs-201-5451326

Not really that similar. The point of trying this method was to avoid submerging the stems in water or disturbing the cutting once they were placed in the bottles. No daily care or attention is required, and the only liquid moisture the stem or roots get is from condensation. This reduces the amount of mold spores the stems will come in contact with.

Before putting in the bottles, I rehydrated the cuttings with an overnight soak in water. Then I gave them a 10 minute bath in 10% bleach to kill surface mold and spores, let them dry, then wrapped the top nodes with clear film, scratched the bottom node, and applied rooting hormone.

This method was designed for rooting dormant cuttings. Once leaves open up the roots will likely need to have their root tips in water as in the summer/green cutting rooting method you posted. If leaves open before roots grow, I expect the leaves would drop unless the end of the cutting was submerged under water.

[AscPete]

Thanks for the additional info.

[cjccmc]

I always look forward to your posts Thai, they are interesting and informative.

Does the paper towel have an advantage over just a small pool of water in the bottom? With your year round season, I would think grafting is another way to go, assuming you can do it much better than I can

[ThaiFigs]

The biggest advantage over a pool of water is that I could try different moisture levels from barely moist to soaking wet. Other than that, I don't think it matters. This one was wetted then wrung out as much as possible.

Happy to share what I'm doing as long as others aren't bored by my posts

Still a newbie by my own reckoning, I've learned so much from the posts of other figgers that I feel I owe it to the community to post what I'm doing in return.

I still suck at grafting. I plan to try again in the coming months. Right now I'm trying an approach graft with a native fig species. I would love to find a compatible native rootstock for F. carica that can handle local water logged clay soils.

[cjccmc]

I like that you can easily see the roots and they have room to grow, will be giving this a try soon.

I've finally had a bit of luck with the rind bark graft. I'm practicing on other softwood trees to see if I can get better at other methods.

For rootstock in the wet clay I think there are fig forums in Indonesia, maybe someone there can help?

[ThaiFigs]

Even more useful than seeing the roots growing is being able to see if mold starts forming on them, and being able to intervene if that starts to happen. The earlier you jump on it, the better the outcome. If you use regular media, you have no idea if your roots are being ruined at the early stages.

[Sas]

Last year I had one cutting of Preto and needed to make sure that it roots for me. I used an SIP, kept it next to a sunny window and added water from below. In order to be extra careful, I initially covered the top with clear plastic cup to prevent the moisture from escaping. Once I see active growth, I remove the cup. I only add water from below, and make sure that the reservoir is always full.
As for the soil, I just use moisture control potting mix. Any soil mixture would do as long as osmosis is the mechanism by which the cutting gets its water. I've used this method for all my high value cuttings. It works.

[ThaiFigs]

While it's possible the cuttings lost some vigor over time, they did manage to grow roots and shoots before failing, and I saw the same drop in success with fresh cuttings from my own garden. So vigor alone is not the problem, though it could certainly be a contributing factor.

[Sas]

My observations are not scientific, but I had cuttings root and then failed to push new leaves.
I see this more often with stored cuttings. Last year I dumped a whole bunch of cuttings into a black garbage bag with moist potting soil and kept them in there for about a month. They all rooted but only a fraction became viable.
Also some varieties are very difficult to propagate, that's why many prefer an Air Layer to a cutting.

[ThaiFigs]

Yes I've seen that also. Too much rooting hormone can cause that. So can cuttings that have run out of stored energy, or didn't have much to begin with. Or pythium can kill the roots. Or snails eat the buds. I've suffered from all of the above at one time or another.

[lilfiggy]

Great posting and a good cure for moldy cuttings which was my bane this year. With the high temps and humidity here I was extra careful and still croaked some prizes. Keep posting wonderful ideas friends. Just think even though we lose some how many we save with all the tips the members share. Good Job.

[ThaiFigs]

Thanks for the link to the dropping water level method. Going to try it with this fresh air layer before I pot it in media. This also gives me a chance to kill off any pythium on the roots before potting (the water has peroxide)

Edit- Having just followed that thread to its conclusion I have to say it really went off the rails by the end. Too bad as it had some interesting ideas being discussed there.

[cjccmc]

For my last few "high value" cuttings I decided to try heating the potting soil to about 180F in a microwave to kill off any potential disease. Now after 3 weeks I have mushrooms sprouting in the middle of the soil and circling the outer edge of the cup . I don't know how those spores could survive the heat or maybe they rode the wind and landed there in the 30 minutes or so while I let it cool.

[ThaiFigs]

Microwave ovens are well known to be a poor means of sterilizing. The heat is both uneven and inadequate. Use a pressure cooker next time And yes, spores will settle on a surface while it's cooling. That's why tissue culture is done in laminar flow hoods.

[bamafig]

Will the tender roots survive removal from the bottle?

[ThaiFigs]

Aeroponic roots are somewhat less fragile than hydroponic roots. That said, they are still tender and require careful potting. I use fine dry media and sprinkle it into the cups, then tap the cups to settle the media around the roots. I do this a little at a time until the cup is full, then water thoroughly.

[don_sanders]

I'd be curious to hear your percentages when you ramp up production

I'm pretty settled on damp peat moss but it's good to see other options.

[ThaiFigs]

This was just a very limited test, obviously. Next will be a test with multiple cuttings in a 5 gallon bucket. Also I will experiment with smaller 2 node cuttings. Stay tuned