It works best to be pruning blackberries in the spring of the year. It's also much easier to prune and pick the thorn less blackberries.
There’s an advantage to pruning blackberries in the spring verses the fall. Extreme cold temperatures might kill some of your blackberry canes.
When you prune blackberries in the spring, you can decide which blackberry canes you want to keep and which ones you want to prune. You’re going to prune out any canes that were damaged during the winter.
Prune your blackberry plants before they begin to leaf out.
All the blackberry canes that produced fruit the previous year should be cut off at the roots. The old canes won’t produce fruit.
The new growth is green and the old growth is brown. If you're not sure, check to see if there are any old berries on the plant. It's an old cane if it has old dried up berries on it.
Last year’s new growth will produce this year’s fruit. This new growth should be pruned as follows:
The canes leaf out and grow vigorously during the summer. If the long canes get out of control you can give them a “haircut” or create new blackberry plants.
Return to Growing Fruit from Pruning Blackberries
Also See Growing Blackberries