Cherries are tricky in Southern California. Only a few varieties will fruit here with our relatively warm winters.
Six winters ago, I planted two cherry trees for my mom in her backyard. The two needed each other in order to fruit. The flowers of Minnie Royal could pollenize the flowers of Royal Lee, and vice versa, but either tree on its own would be useless.
After a couple years, the trees started pollenizing each other and making cherries. How cool! Cherries in Southern California — right next to avocados . . . until one of the cherry trees began to decline in health. It had a large crown gall; it soon died. The remaining cherry tree was now a mere ornamental.
“Should we cut it down, Mom?”
“Oh, but those cherries were so good.”
“Should we plant a new cherry to pollenize it?”
“Is there room, with that avocado getting so big?”
“Then, how about I graft in a branch from another cherry that will pollenize it?”
Grafting saves space and money
Doing this would, in fact, be like returning a favor to my mom. In 2015, in my own yard, I planted a Dapple Dandy pluot tree, a tree which needs another tree to pollenize it just like the cherry has its pollenizer need, and I took a branch from my mom’s Burgundy plum to graft in and do the job. It worked swimmingly. (Also see the videos at the end of this post.)
But why didn’t I just buy and plant a Burgundy plum tree near my Dapple Dandy pluot? Unlike in my mom’s yard, I had the space. For me at the time, it was mostly because I didn’t have the money to buy an additional tree.
Maybe you don’t want the pollenizer’s fruit
In other cases where I’ve grafted pollenizer branches into fruit trees, it has been because I didn’t want an entire tree’s worth of that particular variety’s fruit. For example, I grafted a branch of Pinkerton avocado into my Fuerte tree. I already had a Pinkerton tree on the other side of my yard. I didn’t need another Pinkerton tree; I just needed some of its flowers to pollenize the Fuerte.
(Please don’t miss the video at the end of this post showing the unintended fruitset results on this Fuerte/Pinkerton tree for 2019!)
So there you have three reasons to graft pollenizer branches into fruit trees: One, it saves space compared to planting a full pollenizer tree. Two, it saves money. And three, you may not want the fruit of the pollenizer tree, just the pollen, thank you very much.
Which kinds of fruit trees need pollenizers?
And there you have three different kinds of trees which can benefit from having pollenizer branches being grafted in: cherry, pluot, and avocado. There are others: apples and pears, for instance.
However, not all cherry varieties need pollenizers — same with apples and pears. Avocados never need pollenizers to produce a crop, only to bump up production. And there are some types of trees that have absolutely no use for a pollenizer: peaches, nectarines, and citrus come to mind.
But if you have a tree that can benefit from a pollenizer branch being grafted in, how do you go about it? The actual grafting techniques are beyond the scope of this post though I will share some links to help with that at the end. Here I’ll just share my experiences with choosing a pollenizer variety, possible sources for finding a pollenizer branch (scion wood), and which part of the tree to graft it into.
Choosing a pollenizer variety for your fruit tree
For cherries, pluots, plums, apples, and pears, find a variety that will pollenize your tree by referring to the tag that came with the tree and look up the page for your specific tree on the Dave Wilson Nursery website (growers of most of these trees sold in Southern California).
For example, if you have a Flavor Grenade pluot, you read on the tree’s tag, “Pollinate with a Japanese plum.” And the Flavor Grenade’s webpage at Dave Wilson says, “Pollenized by Flavor King Pluot, Dapple Dandy Pluot, Emerald Drop Pluot or Santa Rosa plum.”
That’s actually a bit confusing, isn’t it? Often, you’ll find somewhat different information about pollenizer varieties from different sources. Unfortunately, I’m not aware of a single authoritative resource on this subject. But in addition to the tag and Dave Wilson site, I’d refer to the Sunset Western Garden Book.
Similarly, for avocados there is no great single resource to help with choosing pollenizer varieties. In general though, you want to choose a variety of the opposite flower type and one that blooms most synchronously with your tree. With my Fuerte, for example, I chose Pinkerton because it is an ‘A’ while Fuerte is a ‘B’, and they are both somewhat early bloomers relative to other avocado varieties.
(If you don’t know if your tree is an ‘A’ or a ‘B’, refer to this database of avocado varieties. If you’re unsure if it’s an early, mid, or late bloomer, ask me in the comments section below.)
Finding a pollenizer branch for grafting
Now you need to get your hands on a branch of this pollenizer tree. Here are five possible sources:
-Your own fruit trees
-Friends, relatives, and neighbors
-Nearby garden club members
-Nearby chapter of the California Rare Fruit Growers, who have a scion exchange each winter
-Members of an online forum such as Tropical Fruit Forum
Where to place the pollenizer branch
If your fruit tree is small, say in its first year or two in the ground, then you can likely graft the pollenizer branch into any quadrant or level of the tree and get successful long-term results. I grafted Burgundy plum into my Dapple Dandy pluot tree during the very winter that I planted the small tree. I grafted the Burgundy plum branch in a low spot on the east side of the tree, and it has flowered well and therefore pollenized well, as seen in the abundant pluots I’ve had to thin.
Incidentally, the Burgundy plum branch itself has fruited a little too profusely.
In my experience, having a pollenizer branch within the main tree seems to engender better pollination even compared to planting a pollenizer tree nearby, let alone relying on the pollen of a neighbor’s tree. If you watch how bees fly (especially honeybees), this will make sense. They like to feed on the flowers of one tree at a time, for the most part, rather than flitting from one tree to another.
Bob Bergh, an avocado breeder with the University of California, grafted branches of various avocado varieties into Fuerte trees in a grove in Pauma Valley back in the 1960s and found significantly increased yield. (See Table 1 in Bergh’s paper, “Reasons for Low Yields of Avocados.”)
My own Fuerte avocado tree was already large when I grafted in the Pinkerton branch so I placed it at eye level on the south side of the canopy. I did this because I wanted to make sure the Pinkerton branch got ample sunshine. The north side or very bottom of the canopy of a large tree would not be good locations to graft in a pollenizer branch because they are the shadiest. Remember that you need this branch to flower abundantly in order to provide pollen to the flowers of the main tree, and the grafted branch will only flower abundantly if it gets sufficient sunshine.
If you’re trying to keep your main tree pruned to a limited size, then you may also want to avoid grafting in the pollenizer branch at the extreme outside of the canopy. This branch will need to grow a couple feet in order to produce flowers for pollination. Don’t place it where you can’t allow it to expand like this.
Over the years, you will need to maintain the pollenizer branch’s access to sunlight. This may require pruning back some branches of the main variety if they grow over and smother the pollenizer branch. I’ve had to do this a bit with my Dapple Dandy branches since Dapple Dandy is a more vigorous grower than Burgundy plum.
Does the idea of grafting intimidate you? No problem, provide pollen for your tree in other ways, such as by planting an entire pollenizer tree. You can also buy multi-grafted trees, of course.
Resources to learn grafting
Does the idea or utility of grafting fascinate you? Then here are some resources that I’ve found helpful.
For grafting deciduous fruit trees, see these resources by Chuck Ingels. He wrote and edited the book, The Home Orchard, which has an excellent chapter on grafting that is full of photos. Also see this slideshow on grafting that Ingels made.
For grafting avocados, the best resource is Propagating Avocados.
Here is a video showing the overlapping bloom — and therefore, cross-pollination potential — of my Dapple Dandy pluot with the Burgundy plum grafted in:
And here is a follow-up video showing the actual fruitset from this Dapple Dandy tree along with an adjacent Flavor King pluot tree:
Finally, here is a video of the Pinkerton avocado branches grafted into the Fuerte tree shot just after the flowering finished in spring of 2019. The Pinkerton branches were meant to be the pollenizers, they were meant to create more Fuerte fruit, but . . .
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