Saturday, April 2, 2016

Grow Big Blueberries in Grants Pass

Southern and Northern blueberries at Bimart.  Note the old leaves on the Southern.

There are a lot of blueberry plants in local stores this year, two kinds.  Northern blueberries have large leaves, thick, stiff stems, and are deciduous; their leaves turn bright red in the fall and then fall off.  Southern Rabbiteye blueberries take our hot summers better; they have thinner, more arching growth, and smaller leaves that turn various colors in winter but are semi-evergreen, holding most of their leaves through the winter in this area.  The flavor of Northerns may be better.

South and North together in my garden.  The old leaves on the Southern bush didn't get cold enough to turn color.  Both plants were transplanted a few years ago; the Southern is several years older.

They don’t like to be planted into plain soil, unless it is exceedingly light and rich, like potting soil. In fact, they grow remarkably well in large pots, more than 2 feet wide.  Otherwise, 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.  Six inches is a great depth for spreading compost to make rich, light soil after it is worked in by worms.  Unlike most other shrubs and perennials, blueberries roots will sink into the soil as the compost is worked in by worms; most other potted plants will sit on top of the soil as the compost is worked in and are left high and dry.
Cover that compost with coarse mulch like ¾” nugget bark, walk-on fir bark, 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.  It is vital to not let the soil be exposed to sun.  Bark protects and insulates soil when the leaves have been pulled into it by worms.
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 at any time.  Indeed, most garden plants prefer a little less heat and a lot more humidity than we have in Grants Pass. 

A standing mister. These put out a finer mist than emitters bought to attach to irrigation line.

           The key to getting fast growth and big berries on young plants in our area is keeping a mister running nearby through the heat of the summer days.  It does not cause fungal infections, and helps many plants grow over a wide area of the garden.  Misting with well water can mineralize the soil, reducing acidity; acid fertilizer can counter that.  After they grow a deep tap root, misting is not so necessary.
An incident shows how vital misting is here.  A customer forgot to turn on 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 or flavorful.
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Gardening is easy if you do it naturally.  Litter is tagging, marking the territory of the disorderly.
Rycke Brown, Natural Gardener          541-955-9040