This November I tried something new. I place 6 cuttings inside a 5 gallon bucket and covered it with a white garbage bag. The cuttings were taken on 11/8/19. They vary in diameter from slightly smaller to slightly larger than a pencil.
The cuttings were rooted in fine Turface. The bucket was placed in a room with lots of artificial light. The room gets to about 75F during the day and 65F at night. At least once a week I removed the garbage bag to water and inspect.
Today, 12/14/19, I removed the garbage bag permanently but will leave the cuttings in the bucket to let them acclimate to a less moist environment.
All of the cuttings are still green and have lost no leaves. Five look solid, when I wiggle them they feel firm. One does not and I suspect it has not rooted and only stayed green due to the humidity.
Several have roots out the bottom of the pot and several have thrown aerial roots. I have rarely had cuttings throw aerial roots.
I will let them continue to grow in these pots until spring or later. In my experience if cuttings are left in Turface too long they form dense mats of Turface and roots that are difficult to ease apart when repotting. So it is better to repot before this happens. In the flexible plastic pots I used you will see the sides bulge if they are left too long.
This morning I repotted the 6 rooted cuttings. They were repotted into shallow containers with equal parts akadama, pumice, and bark. I bare rooted them and trimmed the roots. Pictures below. Of the six 2 had grown vigorously (lots of roots out the bottom), 2 had grown well (some roots out the bottom), and 2 had grown less well (few roots out the bottom). Interestingly the growth corresponded with the thickness of the trunk of the cutting with the larger trunks growing most vigorously and the smallest the least. Those in the middle turned out to have the best roots to work with. The vigorous growers had blocks of root inside the pot that were difficult to separate and lots of escaped roots out the bottom I had to cut off. Those in the middle had roots easier to comb out. And the lessor just didn't have a many roots to work with.
Below is one of the middle ones where the roots combed out easily.
Below is one of the vigorous growers where the roots were not as good after removing those outside the bottom of the pot. You can't see it in the last picture, but I used a thin piece of aluminum wire loosely wrapped to bring the aerial roots coming off the trunk in to the trunk.
I just started another batch using narrow leaf cuttings this time. I have had troubles in the past rooting narrow lead, so this should be interesting.
Awesome results for striking cuttings! How often did you need to water under your conditions? I am curious if a larger particle soil could be used, or even air pruning containers. Thank you for sharing your new technique, and I may duplicate it with a changed soil or container and report back how things go.
Within one week of removing the plastic bag the aerial roots had dried out. They were still white and not lignified when uncovered so going from ~100% humidity to ~50% was not good.
Whenever I prune I try to root interesting cuttings. Using a bucket was a new approach. The cuttings are either developed on their own or added back to the parent as graphs. Aerial roots weren’t the objective.
Thanks for the idea David: Is your intent to find a method to grow aerial root or another way to propagate cuttings, or both?