Spring arrives, and you plant a pear tree and baby it all summer long. In late March, branches are covered with white flowers, which seem like a sure sign of success to come. Then comes June, and some of those blooms turns into fruit that’s setting, but there is just three or four pears on the canopy, not heavy clusters. What gives? Did something go wrong? Test the soil, check for pests…but the truth is that the greatest possible gardening problem you may have solved was the need to create a pollinator for your tree.
Pear trees don’t self-pollinate very well at all. Unlike an apple or cherry tree, which will often be able to pollinate itself to set fruit, European pears almost never does. So remember this: It’s not necessarily proximity that counts, but rather variety. Two Bartlett trees growing side-by-side won’t improve your crop. Why? They are identical twins and genetic clones of same thing. (One can’t pollinate the other.)
Why Your Pear Tree Needs a Friend
To be successful, you’ll need to have a second kind of pear nearby, specifically, a different cultivar with approximately matching bloom date. They do group up these relationships visually so you can easily see what works well together. So for instance, if you planted a Bosc tree, plan to plant a Bartlett or a similar type like an Anjou near it as well. Why? Their bloom windows overlap a lot, and those are the combinations that work. That’s not proximity talking, that’s timing.
If one tree bloom two weeks earlier than the other, bees don’t have anything to connect. By the time the later bloomer has open flowers, all the pollen from the early bloomer is long gone. The rules is a little different for Asian pears. Their fruits, such as 20th Century, or Hosui; are round and crisp, not pear-shaped, and partially self-fruitful. That means you may well have some fruit even from a lone tree… But modestly, at most. Still, you can double (or triple) your crop by cross-pollinating.
And don’t just think about that if you want an Asian pear: these are lower-chill fruits, which also makes them better adapted to warmer climates different than the ones European pears need to break dormancy. In other words, if you’re in zone seven through nine, this difference matter a lot. A traditional Anjou planted alongside other trees might flower erratically, and bear poorly. Asian types are different, though, since they need less cold in winter to reset their biological clocks.
But then there’s fire blight resistance, another trait you don’t think about much until you need it. This bacterial disease likes warm, wet springs and can devastate an orchard’s bloom in a single night. Humid-climate-hardy varieties such as Harrow Sweet and Moonglow are specially bred to resist this problem. Moonglow in particular is rated as an especially good pollinator for other varieties and is also able to fertilize itself (so-called self-fertility). It bridge the mid-early bloom period between the earliest Asian varieties and those from Europe later on.
Put one next to your regular trees; not only will you get higher total output, but it also helps reduce the risk of losing everything to infection. It is a smart investment in weather insurance. A savvy investment in weather insurance. Surprisingly enough, success also depends on how far apart things are: If the bees’ food source is at their feet, they won’t travel very far. For easy movement of both native insects and honeybees between trees, keep your pollinator partners within range, say, no more than 50 feet apart.
You may already have everything you need (that’s my excuse for having only one pear tree): If there’s a compatible pear tree across the fence in your neighbor’s yard, all the better. Get to know your immediate neighbors, and check their bloom times (it’s a free resource most homeowners overlook).
And yes, thin the set fruit as well. Too much of a good thing will break off branches and cause the tree to bear every other year (alternating years of huge crops with none). Leave a pear every six or so inches instead, and redirect its energy from quantity to quality. Consistency is not only the key, it’s the goal. There is no need for your single tree to feel lonely anymore if you give it the right company. You should of planted another one sooner.