Tuesday, February 23, 2010

Hardwood cuttings of roses.

Back in early January I decided to try my friend Simon Voorwinde's technique for rooting hardwood cuttings of roses. This technique could prove useful for cultivars that might otherwise be difficult to propagate by softwood methods. This is Simon's technique:

"All you do is make all your cuttings somewhere around 15-20cm long (I cut the base with a sloping cut behind a bud), remove all their leaves as they harbor lots of fungi etc (you could dip them in some kind of fungicide but I don't tend to bother), bundle them up and wrap them in newspaper, put a rubber band around the top and bottom to keep the whole thing together. Run the newspaper under a tap to moisten it, allow all excess to drip off, then seal it all in a plastic bag and forget it for a while. Some will begin callousing after only a week.

When they've started callousing pot them on as you would normal rooted cuttings and keeping them humid until leaves and roots begin to appear. I have a few large clear tubs (about 140 litrres so nearly about 70cm long by 50cm wide and about 40cm tall) that I put a 10cm layer of moist perlite and peat in that I plant the calloused cuttings straight into, put the clear lid on it, put it outside in a shaded position (as the sun will cook them quickly) and they are ready to begin hardening off in just a few more weeks. With my multiflora cuttings I do this except instead of planting them in the tub I stick them straight in the ground after pre-callousing them and they are away in about a week and I tend to do about 50 at a time. I do this at all times of the year and it occurs faster in the warmer months than the cold."

The photo illustrates my results with one of the Kim Rupert Gallica hybrids I use in breeding. Cuttings were taken from a fully dormant plant and placed on top of my fridge for about 6 weeks. As you can see these calloused easily and have roots well formed, ready to pot up. I would suggest experimenting to find the ideal stage for potting these up; some varieties might work best if potted before roots formed and others might fare better with roots well on their way.

11 comments:

  1. Feel free to correct the typos and grammatical faux pas! I often cringe when I look at my own posts on RHA because I tend to think at a million miles/hour and type at about two! By the time I get to typing something I'm already thinking of something else... and I hate not being able to go back and edit the mistakes... of which there are always many *sighs*

    George, from RHA, mentioned this technique to me first about the same time as another good friend of mine; David Mears did as well. David's a rose horticulturalist and worked for many years for a cut-rose enterprise in Sydney where this technique was routinely applied to strike cut-rose varieties that were grown hyrdoponically, grown hard and fast, and then replaced with fresh stock. A little while later I received some cuttings from Andrew Ross, of Ross Roses (that were meant to be 'Si' but clearly are not as their flowers look just like those of 'Popcorn') with instructions to do the same. They all did things a little differently but the principles remain the same. David's method is one adopted by commerical growers in Australia for the production of rootstocks (though I wish they'd use seedlings instead). What they do is cut the rootstock cuttings and bundle them up with garden twine or budding tape and sit them upside-down in an empty bucket and then cover the ends with moist newspaper. This requires you to keep the paper moist, however, as it is not enclosed in a plastic bag of any description making this technique unsuitable for me because I would probably forget them and end up with a bucket full of kindling.

    And... you know how one good idea tends to spawn another... I've been looking at DIY plans for a pretty simple gadget, sold as a cloning machine, that is based on a similar principle again.. that of aeroponics. I haven't had time to put much thought into it yet but I think it would be a very cheap and successful technique for striking roses and would cut production time and infection from soil/potting mix borne organisms dramatically... I need to read more about it first before beginning to put together any materials and equipment... might blog about it one day when I get time to do it.

    How hard, in general terms, would you say these cuttings are to strike by conventional methods Paul? Do you think there is any advantage in doing it this way over more conventional methods? I currently have a bag of these newspaper cuttings in made up mostly of Teas and found roses from Bishop's Lodge ('Lady Hillingdon' calloused after only three weeks with great big fat callouses). They too are callousing up really well and have taken only 4 weeks to get nice callouses on them. I tend to lose a few potting them up and I would also recommend some experimentation around the post callous stage treatment to minimise loses. I also find that inside the bags lots of buds will break and fresh chloritic growth will appear that melts as soon as they are planted out... I tend to think that any advnatges are lost at this point because they become quite labour intensive to maintain once they are turned loose... or maybe I am just not attentive enough to ensure success form this point onwards.. the bag and forget strategy works well for me LOL. Recent attempts with 'Mutabilis' were maybe a little TOO successful. I put about 50 in a couple of sheets of newspaper... they calloused in just two weeks. I potted them all into one big pot and it seems that every single one took... now I have to try and work out what to do with 50-odd 'Mutabilis' plants! Hmmmmmm. 'Immensee' calloused in the mail on the way down to me prepared in this way and 'Contance Spry' had about 70% success after only 3-4 weeks to callous stage. I haven't ever left them in long enough to form roots in the bag. I'd like to try something really hard now. I should note that EVERY attempt to strike florist roses like this have failed for me so some were just never meant to strike I think.

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  2. I used this method with great success for R. Fortuneana, to strike it as hardwood cuttings in the winter. After the callous develops a nice seal over the cut base, I then plant directly in a mix of soil with organic matter including decomposing leaf litter, and keep the medium on the dry side of moist.

    Actually, this method may work for your difficult to propagate striped sport of 'Jocelyn' Paul?

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  3. I'll have to give this a try. I totally failing at getting softwood cuttings to root.

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  4. Interesting method.
    I want to try it, but what about the temperature?
    You say- seal the bag and forget about it. Where? At what temperature?

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  5. corina,
    Put the bag anywhere in the house where it will be away from direct light, and at average home temps. (IE; 70F give or take)

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  6. Thank you, I wil try it these days.
    I am gald i found this other blog of yours, I was so sad that there was no mo activity o the old roses one. Such beautifull descriptions of old roses, I got a passion for them from that blog.

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  7. Hi Paul,
    I have been very interested in Simon's technique for callousing hardwood cuttings (mostly OGRs)- sounds too good to be true. For me, at least, it is too good to be true. After 4-5 days of storage, all I get is mold where callous should be (probably botrytis). I have tried a mild solution of Bayer Rovral to soak the cuttings before wrapping/storing them, all to no avail.
    Any thoughts, insights, remedies would be greatly appreciated. I want to make this technique work - it sounds just like what I want.
    Bogey von Bogen

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  8. paul,
    i've tried the method and it's working! thank you so much for sharing this! nothing more than an organic rose hardwood, a garbage bag, a wet tissue paper and some patience! :) thank you!

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  9. paul, I don't know what happened!
    all was just fine, the cuttings had green leaves, but suddenly they dehydrated ... and the wood went brown and they are now dead :(
    any idea?

    thank you

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  10. Andrevs,
    Its hard to say without knowing more about the conditions under which you stored the cuttings. Just because cuttings produced leaves doesn't mean they had roots, and without roots, they are guaranteed to fail. Try again!

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  11. Hi Paul,
    I'm living in South African and always read anything from you if I come accross it. I am a keen rose grower and have just yesterday got a seedling accepted (in principal) by our local rose genius, Ludwig Taschner. I've used the baggie method with great success but are certainly going to try the newspaper method as well. Wish I could send you a pic of my seedling. It's called Supernova, and an exremely unusual rose. Maybe you can e-mail me your address and I can the post the pic to you. E[mail me on ria.russouw@gmail.com

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