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Starting Japanese maples, Acer palmatum cultivars, from cuttings is not for the faint of heart, but it can be done. It's probably not a good starter species though. Work with some easier species like willows and elms first to get some experience.

You likely made a number of mistakes. First, it is probably too late in the season to be taking cuttings. Japanese maples are best when taken in the spring just after the new shoot growth hardens a bit. For most of the N. hemisphere, this is during the month of June. Catching the growth at just the right stage of hardness is a bit of art as well as science.

Is this "red" Japanese maple a threadleaf cultivar (dissectum)? If so, forget about it, these are notoriously difficult to root from cuttings, even for experts. Any of the broadleaf cvs stand a decent chance. Fortunately, most of the broadleaf dwarf cvs are pretty easy to root.

Your hormone may not have been strong enough. For good rooting percentages, you need a fairly high IBA content. I use 1.6% (Hormex 16) for most of them. Homex 8 will work for the easier to root cvs.

If they shriveled up that fast, then your environmental conditions are not suitable. You have to provide very high humidity and controlled sunlight to limit the transpiration which will cause wilting. Some species will go ahead and root even if they lose their leaves, but Japanese maples usually just die after being stressed. This is not easy to achieve, even for the professional. I have been doing this for twenty years and I am still learning new tricks (see my blog below for a wrapup of this year's efforts).

Your medium may have been too dense and caused the stems to rot. Getting the medium right is very tricky. It must be highly aerated because, at first, it contains stems, not roots, and stems will eventually succumb without proper aeration (actually roots do too). So you must have this perfect water/air/soil interface. I use screened perlite with just a bit of peat moss.

It can take a long time. My 'Bloodgood' cuttings came out of the mist house after about 6 weeks and are now pretty much fully rooted. The dwarfs though, 'Kiyohime' and 'Yuri Hime' are just now beginning to root after 8 weeks under the mist.

Then you have to over winter them properly. New cuttings don't want to stop growing at the onset of winter because their natural growth cycle has been delayed. But they are also inordinately susceptible to freezing, especially the roots. So you have to figure out how to protect them, prolong the season, and yet still give them a sufficient dormant period. Keeping them inside is not an option, even for rooting them out, they must remain outdoors, or in an unheated greenhouse in winter.

For much more detailed information on general cutting propagation basics see this article at my website:

http://www.evergreengardenworks.com/cuttings.htm

Brent
EvergreenGardenworks.com
see our blog at http://BonsaiNurseryman.typepad.com

15-Aug-2006	#5
Brent Evergreen Gardenworks Join Date: Sep-2003 Location: Northern California Country: US USDA Zone: 8 AHS Heat Zone: ? Posts: 311	Starting Japanese maples, Acer palmatum cultivars, from cuttings is not for the faint of heart, but it can be done. It's probably not a good starter species though. Work with some easier species like willows and elms first to get some experience. You likely made a number of mistakes. First, it is probably too late in the season to be taking cuttings. Japanese maples are best when taken in the spring just after the new shoot growth hardens a bit. For most of the N. hemisphere, this is during the month of June. Catching the growth at just the right stage of hardness is a bit of art as well as science. Is this "red" Japanese maple a threadleaf cultivar (dissectum)? If so, forget about it, these are notoriously difficult to root from cuttings, even for experts. Any of the broadleaf cvs stand a decent chance. Fortunately, most of the broadleaf dwarf cvs are pretty easy to root. Your hormone may not have been strong enough. For good rooting percentages, you need a fairly high IBA content. I use 1.6% (Hormex 16) for most of them. Homex 8 will work for the easier to root cvs. If they shriveled up that fast, then your environmental conditions are not suitable. You have to provide very high humidity and controlled sunlight to limit the transpiration which will cause wilting. Some species will go ahead and root even if they lose their leaves, but Japanese maples usually just die after being stressed. This is not easy to achieve, even for the professional. I have been doing this for twenty years and I am still learning new tricks (see my blog below for a wrapup of this year's efforts). Your medium may have been too dense and caused the stems to rot. Getting the medium right is very tricky. It must be highly aerated because, at first, it contains stems, not roots, and stems will eventually succumb without proper aeration (actually roots do too). So you must have this perfect water/air/soil interface. I use screened perlite with just a bit of peat moss. It can take a long time. My 'Bloodgood' cuttings came out of the mist house after about 6 weeks and are now pretty much fully rooted. The dwarfs though, 'Kiyohime' and 'Yuri Hime' are just now beginning to root after 8 weeks under the mist. Then you have to over winter them properly. New cuttings don't want to stop growing at the onset of winter because their natural growth cycle has been delayed. But they are also inordinately susceptible to freezing, especially the roots. So you have to figure out how to protect them, prolong the season, and yet still give them a sufficient dormant period. Keeping them inside is not an option, even for rooting them out, they must remain outdoors, or in an unheated greenhouse in winter. For much more detailed information on general cutting propagation basics see this article at my website: http://www.evergreengardenworks.com/cuttings.htm Brent EvergreenGardenworks.com see our blog at http://BonsaiNurseryman.typepad.com