Has anyone noticed a correlation between jujube leaf size and productiveness? I haven’t paid enough attention in the past, but I was looking at a multi-grafted tree today and noticed that the leaves on the Bok Jo branch were much bigger than those on the surrounding branches. Last year, the Bok Jo branch produced maybe 30 decent sized fruit on maybe 20% of the bush/tree, while the 50%+ Sugar Cane made 6 fruits. Another branch (I think from the rootstock) made a couple dozen small fruits. 3 other varieties on that tree made no fruit, though 2 were newly grafted.
Bok Jo in foreground on right, with other varieties in background:
For the last 2 years, the Bok Jo has been massively more productive than all the other varieties (on a per branch-foot basis) and I thought it was interesting that it also has the largest leaves.
I took some wood from that branch earlier this spring and grafted it onto two other trees. One of the places I grafted it also has very large leaves (at least the ones near the base of the stems- not the newly forming leaves). I need to check the other one tomorrow.
Here’s one I grafted (3 grafts at close to ground level) which is growing much quicker than most of my jujube grafts:
The difference is very noticeable when looking at the tree, but I should try to quantify things (makes it easier to compare…):
Bok Jo: average 2.25" long, 1.25" wide
Sugar Cane (same tree): average 1.7" long, .75" wide
That doesn’t look big on paper, but as best I can figure, the Bok Jo has over twice as much surface areas per leaf (it’s a bit tricky, as jujube leaves aren’t uniformly shaped).
I checked some neighboring trees and none had leaves which were as uniformly large as that Bok Jo graft (made in April 2017). But, the Shanxi Li and the Sherwood both had some large ones, while the Li and the GA 866 were mostly small leafed. Those 4 trees were planted in 2016 in almost complete sun and have produced a total of 1 jujube (Shanxi Li a year or two ago).
Which leaves me wondering:
1.) Is leaf-size just an inherent quality of a given variety?
2.) Is large leaf size an indicator that fruiting is likely?
3.) If #2 is true, is it causal (big leaves being better able to capture solar energy) or correlative (healthy plants make bigger leaves and healthy plants tend to fruit more)?
Has anyone else noticed any patterns?