Blueberry plants REQUIRE soil pH between 4.0 and 5.5 . If the soil pH is too high, blueberry plants will grow poorly and eventually die. The soil in many regions (including parts of Northern Illinois) is neutral to alkaline (pH 7.0 to 8.0), so it must be amended to bring the pH lower. There are several ways to do this. In small planting beds, the soil can be amended with organic mulches like peat moss, leaf mulch, or compost.
Or blueberries can be planted in containers where soil pH is more easily maintained. Dwarf, rather than high bush, blueberry varieties are much more suited to container growing.
Alternatively or in addition, elemental sulfur granules or pellets can be worked into the soil. Elemental sulfur is yellow and will become incorporated into soil over a fairly long time period…several months will be needed. Iron sulfate or ammonium sulfate are rapidly dissolving forms of sulfur and can also be used. They are usually gray or light brown in color.
However, rapidly dissolving sulfur may cause the soil pH to drop too far or too fast and this can damage the roots of blueberry plants which are found in the upper layers of the soil. So, rapid release sulfur can damage roots badly unless it is used judiciously and according to manufacturer instructions.
How do I prepare the soil for planting blueberries?
Soil bed Preparation
First, find a location that is sunny, having 5 or more hours of full sun each day.
Second, test the soil pH. This is VERY important for blueberry plants.
If your soil pH is in the 4.0 to 5.5 range (acidic), then your soil is already in the correct pH range for blueberry plants. If your soil is more alkaline (pH 5.5-8.0), as it is in my growing area, then adjustments must be made before planting.
In my region of northeast Illinois, the soil pH in the bed I was preparing for blueberries was originally 7.3 to 7.5 . This was much too high (too alkaline) for blueberries. I constructed a slightly raised bed using repurposed old pine or cedar 2×6’s and 2×8’s. The boards were set on edge and nailed or screwed to 1x3x16″ pressure-treated lumber stakes (do not use arsenic treated pressure-treated lumber). Stakes were pounded into the ground to stabilize the larger boards.
After setting up the 10′ by 20′ wood frame, the soil was tilled. Then, the following amendments were added to the tilled soil:
- 5-6 bales of peat moss (2 cu.ft. each),
- 10 lbs. of elemental sulfur in the form of yellow pellets or granules. This is slow-release sulfur.
- A few pounds of iron sulfate, a fast-release form of sulfur that supplements iron.
- These amendments were then tilled into the soil.
- Every few months, I checked the soil pH for 1 year.
- Once the pH remained steady below 5.5, I planted the blueberry plants.
- Every year thereafter, the soil pH was tested in the early spring. It showed that the pH usually had risen to 6.0-6.5 . To counter this, 2-4 bales of peat, 4-6 lbs. of elemental sulfur and 1-2 lbs or fast-release sulfur were added and lightly mixed into the soil bed.
- The blueberries have grown well and yield a large number of excellent berries every year for the past 10 years.
A few caveats
**Aluminum-containing soil acidifiers, such as those used for ornamental plants like hydrangeas, should be avoided. The University of Illinois states that aluminum in this form can be toxic to blueberries.
https://extension.illinois.edu/small-fruits/growing-and-caring-blueberries
**Soil pH should be checked regularly with a pH test device of some sort. These devices are inexpensive and are available from a variety of sources. Soil will probably need to be amended each year to keep the soil pH in the acidic range. In my region, this is understandable because the subsoil is clay and below that are vast deposits of limestone. Limestone is very alkaline and has been mined in quarries throughout northeast Illinois for many decades, so soil alkalinity is just a fact of life here.
**Blueberry plants are shallow rooted, so any cultivation done around them should be limited and shallow to avoid damaging their roots. Also, during hot, dry weather as in July and August, adequate water should provided to maintain soil moisture.
**Varmints love blueberries. Mice and voles like to tunnel in soft loamy soil like that in the blueberry bed. They also love to eat blueberries and, in severe conditions (cold winters), will also chew the bark from the bushes anywhere they can climb.
Yellow jacket wasps are prone to making ground nests around blueberry plants due to the many rodent tunnels existing there that can be used by the wasps for their nest.
Rabbits will eat the bark and twigs in the winter and the berries in the summer.
Squirrels, chipmunks, opossums, and raccoons will plunder the berries and break the branches.
Deer will eat the entire blueberry plant, leaf by leaf, twig by twig, and branch by branch.
Birds. Birds love blueberries. I love birds and blueberries. What to do?
“Never the twain shall meet”.
Exclude the birds from the blueberries using an enclosure. Commercial operations seem to use audible alarm bird calls, loud booms or pops, and other methods to scare and keep birds away, but these would be hard on neighbor relations in a residential setting.
In a subsequent posting, I’ll describe an enclosure that will keep most varmints away from your blueberry plants. This has been an ongoing process which is still evolving, but is mostly functional though more elaborate than originally intended.
This enclosure is not really my idea. Gene Yale, one of the founding members of MidFex, had a blueberry enclosure in his orchard. When I first saw his enclosure, I thought, ‘I can build something like this too!” So, depending of how handy and how determined you are, you can do something similar.
Interesting Information Sources
https://extension.illinois.edu/small-fruits/growing-and-caring-blueberries
https://southernlivingplants.com/planting-care/a-tasty-task-fertilizing-blueberries-and-blackberries
https://www.canr.msu.edu/resources/michigan_blueberry_facts_anthrancnose_fruit_rot_ripe_rot_e3039
Selecting, Planting, and Harvesting Blueberries
This is the best part of growing blueberries!
Depending on the varieties of blueberry grown, harvest usually extends nearly 2 months from late June to mid-August.
In my blueberry bed, I planted a total of 10 plants. They were chosen for cold hardiness (lowest zones 3, 4, or 5), mature plant size (high bush type, 6-7 feet high), and ripening time (June, July, or August).
| Variety | Zone, Minimum | Begin Ripening |
| Patriot (2 plants) | 3 | June |
| Bluegold | 4 | July |
| Northblue (oops, a dwarf) | 3 | July |
| Bluecrop | 4 | July |
| Chandler | 4 | July |
| Jersey | 4 | August |
| Darrow (2 plants) | 5 | August |
| Elliott | 4 | August |
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PRUNING BLUEBERRY BUSHES
It’s not the same as pruning fruit trees!!!
More to come……………