So, you have blueberry plants, but you don’t have blueberries. What’s up with that?
Are your blueberry bushes in full sun?
If not, you will be disappointed. Like most plants grown for food, blueberries do best in full sun (at least 6 hours). They can take some partial shade, but too much shade will decrease flowering and fruiting.
Do you have the correct blueberry varieties for your climate?
Some blueberries require a period of winter dormancy if they are to produce flowers and fruit the following growing season. “Winter chill” is the total number of hours (“chill hours”) below 45°F that a plant needs to bloom. The various varieties of blueberries have different winter chill requirements. Blueberry cultivars can be divided into “high chill” varieties that require more than 800 chill hours, and “low chill” varieties that will set fruit with less than 800 chill hours.
Up North, you need high chill varieties. A low chill variety growing in a northern climate will likely break dormancy too soon, and its flowers killed by a subsequent freeze.
If you’re in the South, you need low chill varieties. A high chill variety growing in the South may never fully break dormancy, and not even bear flowers.
Some popular blueberry varieties and their winter chill requirements are:
High Chill – Better for Northern States
Bluegold – 700-1000
Bluecrop – 700-1000
Jersey – 700-1000
Top Hat – 700-1000+
Reka – 700-1000+
Low chill – Better for Southern States
Sunshine Blue – 0-150
Emerald – 150-300
Jewel – 150-300
Misty – 150-300
O’Neal – 200
Sharpblue – 200
BeckyBlue – 300-400
Southmoon – 300-500
Brightwell – 350-400
Climax – 400-450
Vernon – 500-550
Premier – 500-600
Jubilee – 450-600
Powder Blue – 550-650
TifBlue – 600-700
Since we are a Florida nursery…. Perfect Plants sells all low chill varieties of blueberries. Find all the varieties we offer on our website here.
Looking for a different variety for sale? Ask us and we may be able to help you find it.
You can find more information on chill hours on this Perfect Plants blog.
To find out how many chill hours are normal for your particular location, consult any of the many sources on the web. One of our favorites is at the Midwestern Regional Climate Center (https://mrcc.illinois.edu/VIP/indexChillHours.html). Check out the map below.
Do you have at least two different blueberry varieties?
Most blueberry varieties require another variety nearby for cross pollination. Even varieties advertised as self-fertile will produce more berries if planted near a pollenizer. Any two varieties can pollinate each other as long as they are within 100 feet of each other. If you have only one variety, you will be disappointed in your harvest. Three varieties is actually best for maximum fruit production. More info on cross pollinating blueberries here.
Perfect Plants sells a 3 pack of blueberry plants for optimum cross pollination here!
Is your soil acidic enough?
Like azaleas, rhododendrons, and gardenias, blueberries require an acidic soil. The ideal pH for blueberry plants is between 4.2 and 5.0. Do a pH test on your soil. For a soil pH between 5.5 and 6.5, you should have already adjusted it down by adding aluminum sulfate or elemental sulfur several months BEFORE you planted. (If your soil’s pH is higher than 6.5, blueberry plants will not do well, and it is impractical to attempt to modify the soil.) More info on pH here.
For soils that are close to the ideal pH, but just a little bit too high, you can apply an acidic mulch such as pine needles, pine bark, oak leaves, or, best of all, sphagnum peat moss. You should do this annually around your existing bushes.
Perfect Plants offers a special hand mixed Blueberry Planting Mix perfect for all blueberry types!
Are your blueberry bushes getting enough nutrients?
Mature blueberry plants should be fertilized with a yearly application of an acidic nitrogen fertilizer, such as ammonium sulfate or urea. They might also need phosphorus or potassium. Have a soil test conducted to see if your soil is deficient in these, and apply a balanced NPK fertilizer(like this slow release one Perfect Plants sells) in addition to the ammonium sulfate or urea if necessary. Don’t start fertilizing until the blueberry plant’s second year of growth. Apply fertilizer in early spring, spreading it on the surface in a broad ring around the plant. Do not try to work it into the soil because blueberry roots are very shallow and are easily damaged. Mature blueberry plants should get about 8 ounces of ammonium sulfate per year, and an amount of NPK fertilizer as called for by the soil test.
Did birds eat your blueberries?
If birds are taking too many blueberries, you can protect the bushes with a commercial bird netting, or, better yet, you can keep the birds scared away with pie pans, a fake owl or rubber snakes.
Are your blueberry plants becoming senescent?
Mature blueberry plants should be pruned each year in the dormant season. Remove about a quarter to a third of the oldest and largest stems. Cut them off right near ground level. Blueberries form on stem tips that are one year old on canes that are 2-6 years old, so try not to cut off too many of these.
Maybe your blueberry plant is just tired?
Sometimes when a blueberry bush has an exceptionally productive, high bearing year, it will bear poorly the following year. This is called alternate bearing in plants. There’s not much you can do about this besides taking solace in the knowledge that next year will be better, and enjoying all those blueberries you froze last year.
Is your blueberry bush still a baby?
Don’t be impatient. You shouldn’t expect to harvest fruit in the blueberry’s first season. Actually, you should pick off the blossoms so the young plant can use its energy to develop strong roots and canes instead of fruit. You will have many more years to enjoy the sweet taste of growing your own blueberries!
Happy blueberry planting!