Blueberries difficult to grow in F-M soil, but other options available
If a horticulturist had a choice of any location in the country to ply his trade, where would it be? Why, right here in the Upper Midwest, of course.
Sure, I was born and raised here, so I probably don’t know any better. But I’ve been surrounded by a lifetime of rich garden harvests and pretty-as-a-postcard flowers. Plus, I never worry about alligators or pythons lurking in our raspberry patch.
Did you know the world’s most famous squash, Buttercup, was developed right here in North Dakota in the 1930s? Did you also know that North Dakota has the highest proportion worldwide of trees planted by human hands?
Yes, we garden in a land of plenty. I’m most recently intrigued by growing blueberries and blueberry-like fruits – mostly because they’re healthy, taste great and I’m too conservative to buy them when they’re not on sale.
The blueberry challenge
Can we grow blueberries in our region? We needn’t travel too far east to find them growing naturally, and Minnesota winters are on the chilly side also.
But cold isn’t the problem, the soil is. Blueberries require acid soil, which is found more naturally in forested regions. The preferred soil acidity is pH 4.0 to 5.0, which is quite different from the alkaline soils in the Red River Valley which range from pH 7.5 to 8.5. All currently available blueberry varieties will suffer and eventually die in most of our local soils.
Soil departments of North Dakota State University, University of Minnesota, and County Extension offices can be contacted for soil tests to determine pH levels.
If you’re up for a good challenge, there is a way to modify soil to create the necessary acidity. It should be done before blueberries are planted, not after.
Although there are soil-acidifying compounds on the market, mostly containing sulfur, converting heavy clay alkaline soil to acid is very difficult. A soil mix high in organic material like peat moss or leaf mold is needed.
The best method for experimenting with blueberries is to create a slightly raised planting bed with its very own amended soil mix. For two shrubs, you will need a planting bed 2 feet wide, 4 feet long, and at least 15 inches deep in which to place a new soil mix. A wood or similar frame will contain the mix, and the bed can be partly in and partly out of the surrounding ground level.
Fill the bed with a mixture of 4 bushels peat moss, 2 bushels loam soil, and 2 cups of wettable sulfur, available at garden centers. Plant the blueberries and water well.
In future years, the mix will settle and decompose, so you’ll need to add soil, peat moss and sulfur. If you live in an area with sandy or gravelly soil, you don’t need to build a raised bed. You can excavate an area of proper size and fill with the soil mix.
If you’re up for the blueberry challenge, choose varieties that were developed by the University of Minnesota, like Northblue, Northcountry, Northsky, St. Cloud, Polaris, and Chippewa. Although blueberries will produce even if only one is planted, production is much better with two different varieties. Shrub height is about 18 to 30 inches with a spread of 24 to 48 inches.
Better than blueberries
If excavating soil, lugging bales of peat moss, and purchasing sulfur doesn‘t intrigue, there are two nutritious, well-adapted, fully hardy fruit options.
Juneberry has been nicknamed the blueberry of the north. Canadians call it serviceberry, Saskatoon blueberry, or just Saskatoon for short. Amelancier alnifolia is native and grows to a height of 6 to 15 feet, becoming a large shrub or small tree depending on growing conditions.
Juneberries do well in our soil, so no extra fuss is required. Varieties now available in the nursery trade like Martin, Northline, Honeywood, Regent and Smokey were selected for larger, higher quality fruit than types growing wild.
Another blueberry substitute is relatively new to fruit production. It’s the honeyberry, also called haskap. A member of the honeysuckle group, Lonicera caerulea is native to Siberia and the northern islands of Japan. Cultivars were introduced into our country in the 1990s.
We’ll be hearing a lot more about honeyberries, because they are extremely hardy, delicious and easily grown where blueberries fail. The rounded shrubs grow 4 to 6 feet high and wide.
Elongated berries are blue when ripe. They are delicious for fresh eating, with a blueberry flavor possibly mixed with a bit of black raspberry. Named varieties are available at several local garden centers. Two different varieties are needed, and one should be noted as a good pollinator.
See why this region is so bountiful? We have fine alternatives even if blueberries continue to pout. No wonder I like it here.