Start now for planting blueberries in spring

Ah yes, the blueberries are starting to come into the stores and will soon be ripe in our gardens. Smothered in the thickest cream you can find, they are my definition of July.

OK, so the cream isn’t the healthiest thing to put on them, but research has shown that the berries themselves are high in antioxidants, vitamin C and dietary fiber and only 81 calories for a cup of berries – plain.

Blueberries grow commercially with abandon on the Pacific Coast of Washington and a few places in North Idaho where soils are acidic enough and moisture is consistent. With the right preparation and care, though, you can grow them in your own garden. Now is the perfect time to get started for next spring’s planting.

The biggest challenge to growing blueberries in most of the Inland Northwest is that they need an acid soil and our soil and water tend to be more on the alkaline side. Blueberries need soil with a pH of about 4.5 to 5.5 to take up nutrients properly. If they don’t have it, they turn yellow and don’t thrive.

Pick a spot that gets full sun most of the day with a little bit of afternoon shade. Stay away from south-facing walls as they can get too hot and the lime from the concrete can leach out and disrupt the pH. It may be easier to grow them in raised beds, especially if you have clay soil. Blueberries have fine, shallow roots and will need a consistent water supply.

Your soil will need to be tested for pH using a soil test kit or by sending samples to a lab. Once you have the results in hand you can begin preparing your bed. Mix equal parts of native soil, organic matter and either peat moss or fine conifer bark and fill your beds. The peat moss and bark will acidify the soil. Add about 2 to 3 pounds of sulfur dust (purchase at the garden center) per 100 square feet of bed to further lower the pH. Let the bed sit for six months and test the pH again, adding more sulfur to get the pH down to 4.5 to 5.5. If you prepare the bed now, it will be ready for planting next spring. Mulch the new planting with wood chips or sawdust to help with moisture control and to keep the pH down.

Blueberries need to be fertilized regularly with an acid fertilizer labeled for rhododendrons. The pH should be checked annually with a home test kit and more sulfur added if needed.

Blueberry plants produce fruit as an early, mid- or late-season crop so if you plan right you can have fruit most of the summer. To get good pollination, plant two different varieties for each season for a long harvest. Favorite mid-season varieties in the region include Bluejay and Bluecrop. Plants are usually sold as two-year-old stock and will take about three years to begin producing.