Depending on your location and climate, the blueberry harvest season occurs from mid-summer through early fall. Once you've researched how to plant blueberries and patiently waited for your bushes to grow, flower and produce fruit, it's time for the berries to fully ripen and fall off into your hand with just the slightest touch.
If your baskets weren't quite as full as you'd hoped this season, a few factors might have prevented a large blueberry harvest. First, confirm that your blueberry plants are best suited to your region, as there are Northern and Southern types. If the plant's growing zone checks out, keep reading to troubleshoot this year's blueberry harvest and find out how to increase your bounty next season.
No Flowers, No Fruit!
You pruned your plants late last season and this year you barely see any fruit — where'd they go?
Blueberry plants produce their following year's set of flowers late in the summer to early fall. To avoid pruning off your future bounty, prune only when necessary and then only about a quarter of a given plant's branches. You can easily remove spindly, crossed or dead branches any time of the growing season without affecting your next harvest season.
Lack of Pollinators
Pollinators — specifically native bees and European honey bees — are crucial for the proper pollination of your blueberry bushes. A lack of pollinators in your area means fewer bees to pollinate your awaiting blueberry flowers.
The best way to ensure proper pollination for a heavier harvest is to plant pollinator-attracting plants near your blueberry bushes. Plant a variety of spring-blooming flowers and shrubs to attract and keep pollinators in your garden throughout the season.
Variety isn't just the "spice of life," it's necessary for most blueberry cultivars to "set fruit" or transition from flower to young fruit. Blueberry plants produce larger numbers of fruit when paired with other cultivars for proper cross-pollination.
Plant multiple kinds of blueberry plants to ensure diversity and efficient cross-pollination among your plants. Genetic diversity among your plants will provide heavier crop yields, and you'll have a wider variety of fruit throughout the blueberry harvest season.
Lack of Light
Blueberry bushes are full-sun plants and in order to produce a fruitful crop of berries, they need all the energy from the sun they can get. If your blueberry bushes are planted in even part shade, you might not see the blueberry harvest size you've been hoping for.
To get the most out of your blueberry harvest, plant your blueberry bushes in full-sun locations with at least eight hours of sunlight per day. Trim back nearby trees and shrubs to allow for ample light to reach your plants and to avoid competition.
Lack of Water
Blueberry plants have shallow root systems and require ample water to produce their crop of berries. Since they also require full sun, their surrounding soil will dry out quickly if not provided with constant moisture.
To fix this, provide your blueberry bushes with a layer of mulch to keep their roots moist and cool between waterings. Be sure to remove plants and weeds from the base of your bushes as they'll compete with your blueberry bushes for water and dry out the soil more quickly.
Blueberry bushes require acidic soil to effectively absorb nutrients and grow into healthy, fruit-bearing plants. For many regions in the United States, the soil pH is too high (meaning it's not acidic enough) and blueberry plants are unable to grow well enough to produce flowers — and therefore, can't produce fruit.
To determine whether your soil is within the right pH for blueberry bushes (a pH of 4.0 to 5.5, according to the University of Minnesota Extension), test your soil using a simple soil tester. The easiest way to adjust the soil pH around your blueberry bushes and increase their vigor is to amend the soil with a soil acidifier — often sold for use on hydrangeas, rhododendrons and azaleas.
Harvesting large numbers of deep blue, juicy berries from your bushes is about as rewarding as gardening can get, but to reach this goal, patience is a must. Small, newly planted blueberry bushes take time to grow and produce plants large enough for mass quantities of fruit. The wait will be worth it as you care for your young plant across seasons; when it does reach peak production, you'll have played a direct role in encouraging that bountiful harvest.
But if you're not the waiting type, you can plant larger, mature bushes or many smaller plants so you can harvest small numbers from each plant sooner.
While many animals love blueberries, birds are the biggest culprit when it comes to blueberries mysteriously disappearing. Blueberries evolved to spread their seeds by way of bird droppings, so it's no wonder they're ideally positioned on the plants for birds to pick.
Unfortunately, if hungry mouths abound in your garden full of tasty fruits, you need to keep birds physically off your plants. Bird netting is by far the easiest and most cost-effective way to save your crop, and it can be removed once you've harvested the berries to allow for continued growth.
By following these tips on how to prevent common causes of a smaller blueberry harvest season, you can encourage your blueberry bushes to flourish and fill your baskets (and stomachs) with the sweet, late-summer treat.
For more tips on growing, harvesting and preserving blueberries, check out Burpee's blueberry growing guide.