Tuesday, June 21, 2011

Progress and assorted thoughts on wrapping

After some discussions on Garden Web and a few private emails, I thought it might be of interest to share some further thoughts about wrapping and show progress of the China rose cuttings which were planted just ten days ago (June 11).

It's guaranteed this will require tweaking to be as successful as it can be in other areas, as does anything else related to gardening. I'd originally felt thicker cuttings were going to be more successful. That doesn't explain the 18 foam cups of China roses (really thin, twiggy cuttings, some a quarter the gauge of an eyebrow pencil)  pushing roots out the bottoms of their soil balls. It also doesn't explain the thin cutting of Escapade developing nicely into a maturing plant in a pot.

I do tend to try to make thinner cuttings longer than thicker ones and that appears to have helped. The China cuttings are all five to seven inches long. For any new shoots sprouting from them, I just cut them off leaving the side buds alone so there isn't a lot of softer growth. The "joints" and increased growth buds appear to help, like the traditional "heel" always suggested to take with cuttings with.

These images show cuttings in 16 oz. foam cups followed by each one's roots at the bottom of the soil ball. Clicking on the images enlarges them for more detail.

Chinas can be difficult to select wood to cut for propagation. There are so many "joints" with new growth pushing out everywhere. I selected wood I could cut the five to seven inches of growth. Any buds which had pushed leaves or new canes, I simply trimmed off, leaving a few growth buds on the cutting so new growth was possible from that sprout once rooted. Some of the trimmed, newer growth actually callused and formed roots. Buds which had begun to push and form new foliage were also trimmed so there was no leaf tissue to rot in the damp paper.

Genetics definitely play a role as some just don't have the genetic ability to form callus well nor to form roots which will support the plant efficiently. Shadow Dancer has been a difficult one to encourage to callus and root. Gauge of wood doesn't seem to matter, nor does cutting length. What has rooted most easily are the actually flower clusters where you traditionally don't expect to find growth buds.

The level of stored nutrients available in the cutting will probably also help determine success. Any pathogens already on the cutting when wrapped should also play a part. I'm not sure how wide the successful range of moisture there is with the paper, but too wet WILL cause failure as they suffocate, drown, rot. I haven't experienced what I might consider too dry yet.

It appears temperatures higher than the sixties degrees F range to hold the wraps are too high and inhibit callus formation.

As I've collected the cuttings, I have dropped them into a bucket of water to hold them until I was ready for processing and wrapping. Perhaps if they are too dry when wrapped, that might play a role in failure? I collected, cut, stripped foliage, bundled and tied together with twist tie with label strung on the tie, then dropped the bundle into the water where they waited for collection to finish. Then, I'd shake off the water, dunk them into the Dip'n'Grow and wrap. The wrap would then go into a plastic bag, sometimes several together, and into the work room.

I haven't tried any really soft cuttings yet. My impression is they would benefit from mist propagation to prevent them from collapsing or rotting where harder wood, perhaps better described as hard wood cuttings, seem more appropriate for the method.

Traditionally, you'd use a flowering stem from a recently shattered flower for propagation. I have used that with the wraps and they have worked. I've also used wood older, more mature than that and that has worked. I haven't used anything newer or softer than that with it. They have just 'felt' too immature.

If it's difficult to squeeze out enough water from the paper, try an old rolling pin you wouldn't mind getting printing ink on. That might  provide a make-shift wringer for your paper. You should be able to squeeze out even more water than possible by hand, and it should be a lot easier on your (MY) hands!