Pruning Blackberries


when to prune blackberries

We have blackberries. Just a small section of canes growing on a portion of our backyard fence. I didn’t plant them. Either the previous owners placed them there or nature was just crafty about placement. Whichever is the case, I have to confess that they weren’t even noticeable until the spring of 2010 (four years after we moved in) when I looked out into the yard and saw a beautiful spray of white flowers over the back fence. Ever since I’ve been making breakfast-time trips to the backyard every spring and summer to add fresh berries to my yogurt. In 2013 we received the most and biggest berries ever! Other than a bit of pruning this spring and training a few pliable canes through the fence I haven’t done much with these plants. They’re starting to get a bit unruly so I decided to look into best practices for caring for blackberries. Namely, my goal was to prune them. Here’s what I found…

Why prune blackberries?

when to prune blackberriesPruning blackberries has several straight-forward benefits. First, pruning helps to encourage growth during the next season. Pruning enables growth in cane strength but especially encourages lateral branching (which is where new berries will come from). Pruning also reduces the ability of diseases to spread.

At the end of this fall I noticed that my blackberries had taken on the same spots as my beans and cucumbers. I’m beginning to notice a trend that plants most impacted by what I’m currently guessing to be anthracnose are often located near a mulberry tree, and my mulberry leaves are spotted as well. There’s certainly more research to be done, but that’s another post. Meanwhile, I discovered yesterday that the majority of my blackberry leaves are spotted and diseased. Time to prune for sure!

When should you prune blackberries?

There are two times to prune blackberries: Spring and fall. In the fall (or better, at the end of the summer when berries are no longer being produced) pruning is done to remove dead or 2-year-old canes. Turns out blackberries only produce food on canes that are two year sold. After they’ve produced you’ll never get fruit from them again. Cut those puppies out to make room for new growth! This is also a time to prune away diseased canes and leaves (although this can also be done in the midst of the season to promote plant health).

At spring time blackberries will benefit from tip pruning where you (brace yourself) cut off the tips. Tip pruning causes the canes to branch out and provide more space for fruit to grow.

How do you prune blackberries?

Pruning blackberries is very straight-forward. Use clean pruning shears and cut the canes off at the desired height. If your canes are not supported, keep them around 3 feet tall. For supported canes, cut them off at the height of your support (i.e. fence). I cut mine about 1 foot short of the fence this year to encourage more growth and to give me time to tie them to the fence this spring before they get too large.

I wasn’t expected my own blackberry pruning experience to be quite so… extensive. Between old growth and disease, I ended up chopping off nearly everything, including new growth. It was a little scary, but these plants are so hardy that I know they’ll come back aggressively. I plan to let the branches dry out a bit over the next few days, chop them into small sections and have a little campfire evening.


when to prune blackberries

Our blackberries in the spring, 2013.

when to prune blackberries

Our blackberries in the fall 2013, before pruning.


when to prune blackberries

Our blackberries in the fall 2013, after pruning.
{Note: Most of the green you see is just the pile of pruned canes piled behind the fence.}

when to prune blackberries

The remaining, healthy canes are now woven neatly into the supporting fence.

I can’t wait to see what the blackberries look like next spring!

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