Hi Sandra, Looks like the last frost date for Dawson's Creek is June5th. http://www.almanac.com/garden/frostcanada.php This site is from Illinois in the US which has hardiness zones 4 to 6. You appear to be in hardiness zone 2 so they may not survive your winters. http://www.urbanext.uiuc.edu/fruit/blackberries.html Canadian hardiness zones map You'll need to find a sunny sheltered spot. http://berrygrape.oregonstate.edu/fruitgrowing/berrycrops/blackberry.htm http://muextension.missouri.edu/explore/agguides/hort/g06000.htm Newt
My experience with blackberries: thornless (Loch Ness) is productive but tasteless. Use braced posts and install support wires at 4 ' and 7'. Get Himalayan plants (not the plants with deeply incised leaves) in the off season. Feed lots of compost and water heavily in the heat of summer. Never allow water on the fruit if possible.
It should be noted that nick's advice above is region-specific. Planting what is commonly known as the Himalayan blackberry (often cited as Rubus discolor but actually Rubus armeniacus) in areas where it is hardy and conditions are right (such as the Lower Mainland of British Columbia) can contribute to plant invasiveness: BC Biodiversity - Noxious Weeds. On the other hand, it shouldn't be a problem in Fort St. John as it is doubtful it would survive the winters without human intervention.
