Tuesday, February 17, 2015

Grow Big Blueberries in Southern Oregon

We are coming into the season for buying young blueberry plants in the market or by mail, though the prime planting season in our area is late fall.  Still, you can plant them into the ground in the spring and expect them to grow well if you provide the right conditions.   
You can also plant a #1potted plant or mail-order bare root into a larger pot and let them grow twice as large over the summer before planting in the fall.  BiMart has #1 potted blueberries in the spring, some of which are Southern Rabbiteye, which are semi-evergreen, turn colors in the winter, and take our hot summers better than Northern varieties, but they don’t tell you which are which.  OneGreenWorld.com is a nursery near Molalla that sells both Southern and Northern varieties, where you can find out which ones are Southern varieties online.  Buying local is always better if they are available, as you’ll get larger plants at a lower price.
          They don’t like to be planted into plain soil, unless it is exceedingly light and rich, like potting soil.  Rather than planting them in the ground, it is better to set the plant on top of the ground and surround it with enough compost to surround and cover the roots.  Young blueberries grow a sponge of roots only 4-6 inches deep in their pots, putting down a deep taproot only after 4-5 years.  Four to six inches is a great depth for spreading compost to make rich, light soil after it is worked in by worms.  Unlike other shrubs and perennials, blueberries roots will sink into the soil as the compost is worked in by worms; other potted plants will sit on top of the soil as the compost is worked in, and be left high and dry.
          Cover that compost with coarse mulch like ¾” nugget bark, walk-on fir, or pine needles, to keep it from drying out and keep the roots cool and moist.  2 inches of leaves in the fall are probably the best mulch to maintain organic matter in the soil, but I like to scatter our copious coffee and tea grounds into the bark after the leaves are eaten.  It is vital to not let the soil be exposed to sun.  Bark protects it when the leaves have been pulled into the soil.
Southern Oregon has hot, dry summers, not the best conditions for growing blueberries, which like their heads in the sun and their roots cool and moist, but don’t like a lot of heat or dryness.  Indeed, most garden plants prefer a little less heat and a lot more humidity than we have here. 
          The key to getting fast growth and big berries is keeping a mister running nearby through the heat of the summer, particularly from blooming to after harvest.  24/7 is best, as it simulates coastal fog.  It does not cause fungal infections, and helps plants grow over a wide area of the garden.
Last year, an incident showed how vital this is.  A customer turned off one mister for a week near an isolated plant that had been producing big, tasty berries.  The remaining berries all stopped growing and immediately ripened, producing little berries that were not juicy and flavorful.      
February 2015 issue, online at GardenGrantsPass.blogspot.com and at the Mail Center, 305 NE 6th
Gardening is easy if you do it naturally.  Litter is tagging, marking the territory of the disorderly.

Rycke Brown, Natural Gardener          541-955-9040        rycke@gardener.com