expert advice on Acer propagation
- Subject: expert advice on Acer propagation
- From: &* <p*@comcast.net>
- Date: Thu, 28 Feb 2008 09:30:40 -0800
I am pasting in the response I received from a dear friend who is an Acer
expert to whom I forwarded this request for information. He is the
greenhouse manager for Quarry Hill Botanic Gardens in Glen Ellen, which
specializes in them and other Asian species. His own personal collection of
Acers (many of which he has bonsai-ed--another passion of his) is
impressive. He sardonically refers to his answer as brief, so those of you
not really interested in the explanation may want to skip this one, even
though it is very informative! :-)
Cheers!
Karrie Reid
Folsom Foothill Gardener
Zone 9
Mrs. Karrie,
I hope you're doing well! I'm looking forward to coming back to Davis soon.
Maybe in a week or two. How's everything with you? Here's my very brief,
clear, very concise response:
Depending on the size of her trees, I'd suggest air-layering several
branches of each of them. And depending on their size, he can make several
own-rooted plants off of each that he currently has. This is a more
flexible means of vegetatively propagating a tree such as this; stem
cuttings require an environment that may be a little difficult to reproduce
at home, especially for Acer, which can be on the difficult-to-propagate
side. Cuttings can work, but I think air-layering maples (when executed
properly) will give a much higher success rate for the home gardener.
Rooting studies on A. pentaphyllum are few and successes have only recently
been reported, for example, and the environment was quite controlled.
Burying the tree's crown deeper is not recommended, regardless of how high
or low the graft union is, as the trees may suffer from crown rot and the
owner would lose the entire tree. A. pentaphyllum is quite rare (possibly
less than 200 TOTAL mature plants left in China- the only place they exist;
I'm not sure about the rarity of the other two species), so any harsh
treatment to the entire plant wouldn't be recommended. Air-layering is also
considered fairly conservative. The owner can choose a pencil-sized branch,
girdle it, apply a dusting of rooting powder or paint on a liquid (mid-range
concentration should be okay, 4000-6000 ppm IBA), wrap it in moist sphagnum
moss, cover it with plastic wrap (closed tight at top and bottom) and then
aluminum foil to reflect light and keep the temp down, etc. Air-layering
could be considered a way of "nursing" a cutting along (similar to a cutting
but still attached to the stock plant)- the layered portion continues to
receive water and nutrients through the xylem while rooting takes place.
And yes, all three species should perform well on their own roots. He
should also know that he can leave the air-layered portion attached to the
parent plant for several years if it appears necessary (might need 2). Of
course it's a judgment call, the new root mass should be in proportion to
the shoot mass of the layered portion before the new rooted plant is cut
off. He should monitor the wetness closely the whole time. Air-layers,
while wrapped in plastic, can be watered with a syringe by injecting small
amounts of water, or the top of the plastic can be opened up and water can
be poured in (just make sure it doesn't FILL with water). After the first
growing season he can carefully remove the sphagnum moss from the roots that
have formed and attach a plastic pot (cut down the side and into the center
of the pot base) around the roots, and fill the pot with potting mix, teased
in around the new roots. For the second year he can leave the pot around
the branch and care for it as if it was an independent plant- fertilizing it
and everything (light fertilizer can also be used the first year, too). He
could then detach it after the second year...
Here's an interesting product; many different ones exist like this:
http://www.rootrainers.co.uk/gardeners/propagationpots/rooterpot
Was that a convoluted explanation or what? Karrie? Are you still awake??
Hope to see you soon,
Corey
