There’s
more to blackberries than the
aggressive, prickly masses you find growing wild on roads and in woodlands.
In
fact, Northwest gardeners can enjoy
home-grown blackberries that are known around the world for their flavor and
quality thanks to the breeding efforts of Oregon State University Extension
Service and the USDA Agricultural Research Service.
A new
publication from OSU Extension
gives details on how to grow tasty, improved blackberries—many without
thorns—that will stay productive for 15 to 20 years. “We have an ideal climate
with warm summer days and cool nights, so our berries reach peak flavor and
quality,” said Bernadine Strik, Extension berry crops professor at OSU.
Commercially,
Oregon growers produce the
highest yield of blackberries anywhere, Strik said, and Oregon is second only
to Serbia for the amount of blackberries sold worldwide.
What’s
the difference between a
blackberry and a raspberry? They are distinguishable by where their white core
remains when picked. The blackberry core remains with the berry and is part of
what you eat. The raspberry core remains with the plant, leaving an opening in
the fruit.
The
three main types of blackberries are
trailing, erect and semi-erect. Trailing berries are considered excellent, with
good aroma and small seeds, but are the least cold-hardy. Trailing cultivars
include Marion, Cascade, Santiam, Black Diamond, Obsidian, Thornless Evergreen,
Boysen, and Logan. Erect and semi-erect berries need summer and winter pruning
and are glossy and firm with larger seeds than the trailing types. Common
cultivars in these groups include Navaho and Triple Crown.
Blackberries produce best in full sun but
will tolerate partial shade, Strik said. “All types are self-fruitful so
you need only one cultivar for pollination and fruit production,” she said. The
fruiting season ranges from mid-June to September, depending on the variety,
and no fruit is produced the first year.
Trailing
blackberries grow well west of
the Cascades, and you can grow them in colder areas with low winter rainfall if
you leave the canes on the ground and mulch them in winter.
“It’s
best to purchase certified
disease-free plants from a nursery, “she said. “Plants from a neighbor could
introduce root-rot, viruses or other pests into your garden.” Plant as early as
you can work the soil in the spring, Strik advises. Any soil is suitable as
long as drainage is good. Blackberries grow best when the soil pH is between
5.5 and 7.
“It’s
advisable to trellis blackberries,”
she said. “You can grow them without support but trellises help prevent cane
breakage from wind. A trellis also provides a neater planting and makes
cultivation and harvesting easier.”
Details on
planting, fertilizing, irrigation, pruning and weed management are available in
the newly revised publication EC 1303, “Growing Blackberries in Your Home
Garden.” A copy can be found at:
http://extension.oregonstate.edu/catalog/pdf/ec/ec1303.pdf