Grafting Experiment

General Discussion
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1

I have just concluded a grafting experiment. I decided to try grafting onto unrooted rootstock pieces and try rooting the newly grafted pieces at the same time that the graft was healing. I wanted to try a different method of grafting that I will call “tongue grafting” (I don’t know what the proper term would be).

Mr. Moore had taught me the method of slicing a thin sliver of bark in the rose rootstock without removing it (producing a sort of “tongue”-like piece of bark). I think that he had said that Burling adapted that method for use with mini trees and had found that making the cut the other direction - cutting upward, with the tongue pointing downwards, provided a more secure graft to help the new grafts from popping off when they started to grow.

I hope that the description above was clearer than what it sounded to me when I just reread this!

Continuing onward…Rootstock pieces were cut into segments, each having 4 leaves attached, the bottom 2 leaves were removed and de-eyed. The selected bud eyes came from 3 different seedling varieties.

Anyway, I decided to use the above method, but with a twist. I grafted the selected bud chips right over the place where the rootstock stick was “de-eyed”. I compared that with doing the same sort of tongue grafting onto the side opposite of where the rootstock sticks were de-eyed.

The newly grafted rootstock pieces were dipped into rootone, and put under intermittent mist for about 3 weeks. They were then removed from the mist and allowed to acclimate in the greenhouse being watered once every other day or so. After an additional 2 weeks, the tops of the rooted rootstock pieces were removed, just leaving the grafted part intact.

The results were as follows:

Successful tongue grafts:

over the de-eyed location = 12/13 = 92%

opposite the de-eyed location = 11/14 = 79%

For an overall rate of 23/27 = 85%

Either way the graft “take” was pretty decent. I’m not sure whether there was a statistical difference between the two techniques. Perhaps a larger number of grafts would clarify an advantage.

Jim Sproul

2

Very interesting. A lot like what the Dutch? called stenting to produce stentlings I think. That was before 1980 I think. I tried budding on the rootstock directly, then rooting those sections that took. Not a good enough take at step 2 to save a year like I’d hoped. Having the mist system seems to be the key to getting something to go.

On the stats, roughly speaking the S.D. is the square root of N, if you are pulling a random sample from a big pot. That’s sort of what you are doing. So 11 +/- 3 would be a decent guess and so it’s not a significant different. Think of it as needing 10 % difference in 100, or 30 % difference in 10 as sample sizes. That’s why Mendel got such a hard time from Fisher. His variation was so small, on relatively small samples.

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Jim, the process of grafting onto understock cuttings is called stenting (see link). I’ve been using this method for about two years (without your success as I don’t have a misting bench) more out of necessity than anything else. i.e. when people send me cuttings that start to die off and in desparation I try to bud them and I don’t have any understocks ready or when people send me budwood and I don’t have any uderstocks ready. I do them two ways and seem to enjoy a higher rate of success by chip budding the stents rather than the traditional T-bud. I also tried another way which seemed to work pretty well. I chip-grafted some scions onto rootstock cuttings and then wrapped them all in moist newspaper and sealed in a plastic bag and left for several weeks. The cuttings struck and the buds seemed to callous up nicely too and it also took up very little space to them. hardening them off was a pain but it seems to speed things up a fair bit. I was stenting onto multilfora cuttings too.

Link: www.rooting-hormones.com/stenting.htm

4

Hah… snap LOL

5

If you don’t have any rooted understock, you can always graft directly on to the living mother plant of the understock.It is easy and quick to do and once the graft shows signs of putting on new growth, you can remove the piece of understock and root it while the graft continues to grow.

You can also use the same technique used by orchardists in splitting the understock cane and inserting a beveled piece of graft and then securing it either with wax or with a grafting tie.

This method is a lot easier than stripping off an eye and hoping you have it deep enough or not deep enough when it is placed in the understock.

6

I would not recommend this. It’s not very ‘safe’… and I’m speaking from experience… I had to pull out two whole large plants because some budwood I grafted onto them were virused… suddenly the whole plant is virused and any future understocks would be too.

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Hi Jim! It sounds like you have some interesting roses you want to propagate. I sure love the photos and descriptions you are sharing about your Hulthemia hybrids. Are you propagating your Hulthemia hybrids?

I love stenting too. A few year or more back I wrote a little description with diagrams for the newsletter about stenting a Rosa eglanteria hybrid I enjoyed a lot that I couldn’t get to root well from cuttings. I did the whip and tongue graft (sounds like the graft you are doing Jim). I love too how it secures things nicely. The whip is just a long angled cut with a lot of surface area matching the diameter of the stems and then the vertical cut into the pieces to wedge together sure secures things.

When I did it I took out all the eyes of the rootstock and the rootstock was pulled leafless. I used a thornless multiflora from Dr. Buck which roots easily and maybe was more forgiving than other rootstocks for stenting. I left two leaves and nodes on the scion and cut back the leaves to a couple leaflets or so each. I parafilmed the graft and potted the cutting with rooting hormone at the base. 4 of the 5 rooted from memory.

A few years back Paul Olsen shared some key spinnosissima / foetida and other hybrids from Canada and I propagated them to distribute. Cuttings of many were failing and stenting allowed for successful propagation. I just had some polyantha hybrids around then and grafted them onto them. I grafted several of each clone and had really good take on most.

In 2005 I was able to visit J&P and that day they were stenting single node stems of their hybrids with a leaf on the scion to Rosa fortun. for the Florida market. THey used just a whip graft without the tongue I think because it is faster.

Somebody associated with Kordes was telling me that in the midst of all the shift to own root production of all rose market types, there should still be a market for people to develop for regional grafted hybrid teas, etc. for especially small growers to keep some great roses that do not do as well own root in commerce (i.e. perhaps some of their nice cutflower Freelander hybrid teas). Maybe stenting would be a nice way for a small grower to do that without field production and still generally have the same benefit of small, shipable liners common to own root plug production. Steve Singer and others sell budded maidens which is great. Little stentlings tend to grow right away (especially with the rootstock buds cut out) which is nice to help get the scion growing.

David

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Using the handy dandy search feature on the RHA newsletters, I find the article that David mentions in the Winter 2001 issue. If you do not have this super reference, please contact Larry Peterson who will see to it that you get one. The price is not bad either for 37 years of 151 back issues. For 25 bucks, what a deal!

9

Thanks Larry! I think that you are right that there was no significant difference, however, I think that I will still prefer the bud grafting directly on the area that was de-eyed. The success rate with this is close to what I get bud grafting directly to rooted cuttings. Previously I preferred T-bud grafting, but I have noticed that the “T” tends to curl open, breaking the parafilm that is used to hold the buds in. You then have to go back and put another strip on or risk having the bud pop off before it has healed properly.

Simon, thanks for the link! I enjoyed the video. I have never tried that method of grafting. It looks like one critical factor is having the understock, and variety to be grafted, to be the same diameter.

Meg, Joe Winchel showed me that way. He would graft to rootstock whips and wait for them to heal before cutting them into segments and then rooting them. I tried that for awhile, but didn’t like the possibility of contamination of the mother rootstock plant, so abandoned that method early on.

David, thank you for your comments. Yes, I am propagating my Hulthemia seedlings. As a group they root exceedingly well. I have a 72 cell tray of 24 different Hulthemia seedlings (3 each) that just finished rooting. It looks like all of them were successful. The thornless Buck rootstock that you use, is it “069”? Joe Winchel called a thornless rootstock that he got from Buck “069”. I used it in breeding my own rootstock.

John, the back issues on the CD are great! Thanks to all who put the work together!

Jim Sproul

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On getting a ‘take’ with a bud graft, the late Johnnie Becnel whose background was in citrus found that he got a much better take on fortuniana by doing an inverted T bud insertion than when the ‘T’ was upside down as most grafters recommended. He also demanded that the rooted rootstock not be watered for ten days for he thought that there was enough moisture in the plant for the budding to take. These variables might be worth a try if you are working with different rootstocks.

Sandy and Bob Lundberg from Bluffton SC were trying a lot of things with their exhibiting and found that stentlings done in a mist table worked well for minis and minifloras. He suggested that the connection not be entire but that the rootstock have a slight airspace at the top of both sides - it worked better for them.