Berries and Brambles Series: Blueberries

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We've recently wrapped up Northern Illinois Berry School in the region with programs in Rockford, Amboy, DeKalb, and Elizabeth. The program was designed to give you as both new growers and homeowners the opportunity to find out more about growing strawberries, blueberries, blackberries, and raspberries along with an introduction on pruning/seasonal management and insect/diseases issues.

If you were unable to join us this year (and there will be more Berry School programs next year), I'll be spending the next couple of blog posts focusing on a modified version of this program for the blog by covering the ins and outs of growing these crops. First up is blueberry.

If you remember anything about blueberry plants, know that the main hindrance to a successful or unsuccessful blueberry crop is your soil pH. Blueberry plants love acidic soils and need acidic soils to really thrive. if you have a naturally acidic soil, you might be fine but for most growers and homeowners, you'll need to lower this soil pH to a more acidic level. You are after a soil pH of 4.8 to 5.2 Don't think you will be able to lower the soil pH after the plant has been planted as the soil pH will limit the availability of nutrients and further lead to worse growth of your plant. For small plantings, you might add sphagnum peat moss or elemental sulfur. Both of these will need to be applied a year prior to planting as it takes time for the pH to be altered. It is not advised to plant your blueberry plants and then lower the pH. Instead of altering your soil pH, you might consider a raised bed. By having a raised bed in place, you may have better control over the soil pH by starting with soil you are adding.

There are three types of blueberry plants which include lowbush, highbush, and rabbiteye. The lowbush is one that is native to Northern US while high bush are commercial varieties that are best for Illinois. The rabbiteye type is common in the southern US and is not recommended for our climate. Varieties recommended for our region include 'Bluejay', 'Patriot', and Nelson among others. You might also talk to other growers in our area to see what other varieties they recommend.

If you plant two varieties, you may have better pollination and higher yields. In the first two years of planting blueberries, you want to remove the flowers as these first years should be spent allowing for the blueberry plant to grow, develop, and not concentrate on yields. Once you've planted your blueberry plants, plant them at the same depth and spread the roots out slight. Add soil and peat moss and water thoroughly. Blueberry plants benefit greatly with mulch. This mulch can be in place for years helping with water infiltration and weed control. Adding to the mulch each year can also benefit your plantings.

Fruit is produced from lateral buds on two, three, and four year old canes. You should not prune for the first 3 years and then on the 3rd year, you should also remove diseased and dead wood, old canes, soft basal fall growth, twiggy growth clusters, and weak lateral shoots. You should allow 1-3 new canes each year and remove canes that are 5+ years old. This may sound confusing when it comes to pruning such as how will I know the cane that is 3 years old compared to the 2 year old cane. You may end up place some kind of marker on each cane to determine the years. This color coded system can help you when it comes to making the right pruning cut. Univ of Maine provides a good view of what the pruning can look like:

In general, you should expect a harvest that lasts from 2-5 weeks and the berry will turn blue before being ripe. The underside will turn from pink to blue when fully ripe.

Next week, I'll get into some other intricacies of growing blueberries.