So you buy a blueberry bush, and plant it with high hopes. In spring, it grows leaves; then it produce flowers. Your bush looks healthy and looks like it will do well. Come harvest time, though, all those branches are bare. Where did the fruit go?
It is a classic beginner’s mistake. Chances are, the cause wasn’t poor care, or bad soil. The cause: the bush was lonely.
Why You Need Two Blueberry Bushes
Unless your variety of blueberry is among those that is self-fertile (and most popular ones aren’t), it needs another, genetically different neighbor on which to set its pollen. You can feed it all you want but without such a companion, you’ll have a smaller crop.
As you’ll see in the visual guide, this makes sense, you can increase your crop by forty percent if you move up from one variety to two that are compatible. That is not a small amount. It is a proper pie versus just a modest snack.
How does Duke compliment Bluecrop? The chart shows that while Duke is an early bloomer, Bluecrop bloom later in the middle of the season. By growing both, you create more overlap for the pollinators, and therefore even if the early bloomers gets hit with a cold snap, they’ve got someone waiting around to be their dance partner, midseason.
And it’s all about timing. This infographic shows a bloom timeline from early spring until late summer, so you are looking for varieties whose blooms will overlap at least somewhat. Two weeks of difference between finishing up and starting won’t be helped by closer spacing or soil tests.
You’ll find some pairings noted there (like Bluecrop and Patriot for an extended season, say; or Misty and O’Neal if you’re in a warmer climate). They are not just random combos. These is calculated combinations to ensure successful pollen transfer when the flowers is most receptive.
Keep pollinators in mind. According to the chart, honeybees do a good job, as do mason bees and bumblebee. In fact, certain crops like blueberries benefit from something called buzz pollination by bumblebees. The vibration help release their pollen better. More native plants will help bring them into your yard if it’s feeling silent; they’ll work for you, and move pollen around in ways no amount of manual effort can.
The other chemical: soil. As the visual guide notes, “the target range for optimal growth should of be a soil pH of approximately 4.5.” Blueberries like it on the acid side; if it is too alkaline, they’ll have trouble taking up nutrients. This means weak blooms and less fruit even when pollination conditions are just right.
Get your soil tested before digging in; it’s worth the effort. To lower the pH, amend the soil with sulfur or pine mulch to get it down to what these bushes prefer.
Blueberries aren’t one size fits all. There is four types: northern highbush, southern highbush, half-high, and rabbiteye. Each type requires a different amount of chill hours and has its own zones.
If you live in an area where winter isn’t cold enough, you won’t want the variety called Duke, which need more than a thousand chill hours. That’s not going to work out well. On the flipside, Misty wants almost none.
Match the variety to your local conditions and to each other. Your patch is an ecosystem in balance, and you set it up that way. Space the bushes so they has good air circulation (no disease). Water them deeply but infrequently, which keeps their roots cool and moist, and mulch deep to help achieve that.
But unless those bushes can reproduce, what difference does all that make? The engine that drives the yield are cross-pollination.
Gardening is about partnership. Not just your partnership with the plant; it’s also about the plants’ partnerships among themselves (and with the insects who comes to visit). Planting two compatible varieties together leads to a richer harvest.
The lonesome bush doesn’t yield much, but the teamed-up pair do.