Here’s my 2021 Jujube data for in-ground grafts on established stocks:
| Size | Grafts | Takes | Pct |
|---|---|---|---|
| Thin (<= 2mm) | 12 | 9 | 75% |
| Medium Thin (3mm) | 19 | 15 | 79% |
| Medium (4mm) | 26 | 23 | 88% |
| Medium Large (5mm) | 34 | 32 | 94% |
| Large (6-7mm) | 35 | 31 | 89% |
| Large-Very Large (8mm) | 13 | 10 | 77% |
| Very Large+ (>=9mm) | 18 | 10 | 56% |
| 157 | 130 | 83% |
Notes on data- excludes a few recent grafts (no time yet to see if they took), Also excludes 4 grafts where I forgot to include the thickness. There could still be a bit of movement in the numbers- hopefully a few more will break bud over the next few weeks.
From this data, I would conclude that thin wood lowers success rate some, but not by as much as very thick wood hurts success rate. You want the Goldilocks wood…Not too big…not too small…just right.
It’s interesting that the 2016 apple results I posted above (post 2109) were a bit different:
So in the 2016 apple data, Medium-Thin and Medium had the most success, while in the 2021 jujube data, Medium-Large was the leader. I have a few possible explanations:
1.) The apple study had a very small sample size (36 vs 157 grafts). The clearest result from it is that when the wood gets too big, the success goes way down. The 2021 jujube data also shows that same result.
2.) Maybe there is a difference in optimal size between apple and jujube wood (jujube being slightly larger, but still not too large).
3.) The categories (ie thin, medium, very large, etc) are subjective and my categorization may have changed over the last 5 years.
To make this meaningful to others, I’ve included an estimate of each size in parenthesis). This is something I came up with by classifying some scions, then measuring to see how wide they are. I don’t measure each scion as I graft them (when I first started in 2013, I did it for a dozen or two, but skipped that for the next few thousand grafts 
). Even when I did measure, the results were often like “4.5-7mm”, as not every scion is perfectly round.
I tried to take a look at it based on the number of buds, bud I haven’t been as careful about counting buds and only have that metric for a bit under 75% of my grafts. Even so, it doesn’t seem that a single bud harms my success rate, as I used one bud 44% of the time and the success rate was slightly above the overall average.
| Buds | Grafts | Takes | Pct |
|---|---|---|---|
| 1 Bud | 71 | 60 | 85% |
| 2 Buds | 31 | 27 | 87% |
| 3 Buds | 10 | 8 | 80% |
| 4 Buds+ | 6 | 4 | 67% |
| No data | 43 | 34 | 79% |
| 161 | 133 | 83% |
What I think does hurt my success rate is if the scion is so short that I can’t really hold it to cut. Like the one in this pic. I only had 3 like that and was 1/3 in terms of take rate. So one bud is fine, but I need a bit of hand-hold.
One thing to consider. If I had a stick with 10 buds, even if the space between the buds wasn’t all that much (like the below pics), I think I would do OK, as long as I made each wedge before separating the bud from the rest of the stick. That would leave only the last bud with nowhere to hold, giving you 9 decent grafts (in a situation where you don’t have much wood and want a lot of copies).
One which hasn’t grown so far:
One which did take:
