Saturday, July 02, 2011

Pruning Raspberries

The most important thing to know is that a berry cane will make a shoot and grow up one summer, but it's the following summer that it bears berries. And then it's done.

Ideally, you will cut all fruit-bearing canes shortly after they're done bearing. It's good to do this in July or August, while there's still obvious and clear evidence of which canes had berries on them. It requires less thinking and less decision-making. Just whack down whatever had fruit on it this year.

If you can get outside in June (maybe 2-5 weeks before this year's canes start setting fruit) and prune or thin, that helps. In the month before the fruit grows, you want to be thinning next year's canes. First, it's easier to thin the new growth when it's shorter than this year's fruit-bearing canes; it looks different enough that it makes the pruning/thinning easier. And easier is better! Second, you don't want the roots and the ground putting all the energy into making new plants (too many plants!) for next summer; you want to be using some of that effort to make plenty of big, sweet berries for this summer. Third, it's loads easier to harvest when there aren't a gazillion shoots out there with the fruit-bearing canes, hiding berries amongst the leaves, making it hard to reach your hand into the thicket.

In fall, thin next year's fruit-bearing canes again. Get rid of the spindly canes. Save the strong, sturdy canes. If you didn't get around to eliminating this year's fruit-bearing canes earlier, do that in fall too. If you expect naughty deer to invade your berry patch, or if you're worried about snow and ice harming your canes, don't prune as severely in fall, but do part of the job in fall and finish your pruning/thinning in spring. But the general rule of thumb is not to have fruit-bearing canes any closer to each other than 6-8" in any direction. If you're starting out your patch, and set down roots 18" apart as you're told to do, then you can have 2-4 canes coming up from the one set of roots, assuming you've got 12-15" between clumps of canes. When you've got your raspberry bed established, you'll want it to be rather solidly spaced, about 12" wide and who-knows-how-long. If you have more than one row of canes, make sure there is ample space between the rows for you to move, hoe, prune, and harvest.

The hardest part of raising raspberries is all the killing. It's so important to thin out baby plants, chop off plants that appear to have potential, and not try to grow too many canes, thinking that "more canes equals more berries." Nope. It doesn't work that way.

I have another week or so before my raspberries ripen. In the meantime, I need to grab the cherries off the tree before the birds beat me to 'em. Visions of pie are dancing in my head.


  1. Wow, I had no idea it was so involved. My grandma buried her compost in her garden including some rotten raspberries. A few years later she had a huge raspberry patch there. I don't think she ever pruned them or did more than pick the berries. Wish I could ask her. I know she had tons of plants close together. She would pick and pick and eat as many fresh as possible and then freeze tons. She had two raspberry patches-the one that she planted and the one that grew from compost. The one she planted was farther away and she didn't go pick berries there as often and she didn't need to because the one from compost grew so many berries right out her back door.

  2. I know they grow wild without tending. Even so, I know people who've inherited untended raspberry patches that bore much more bountifully after pruning out the old branches and thinning the new growth. Maybe it depends on what kind of berries you have??

    Ewe, I've had several people ask me recently what to do with raspberry patches. It's really pretty easy. They seem to want to grow and bear fruit. My pruning and thinning is mostly to make it easier for me to harvest the fruit: for the fruit to be bigger, for there to be spaces to walk between rows, and for there to be places to see into the thick rows and put my hand in to pull out fruit.

  3. THANK YOU for writing this out. I've been having trouble wrapping my brain around the biennial nature of summer bearers!

    And holy cow, you're really taking out something like 2/3rds of the growth each year, aren't you? Crazy.

    Now, my brother was telling me about a method where you bend over the tall new-growth canes to the ground to root into a new row; that becomes your fruiting row for the next year, and you simply destroy the current, fruited row. You keep the whole lot marching back and forth across an area. I wonder, would that simplify things? You could be enriching the soil this year where the row will be next year, too.

  4. The switching rows year-to-year? That's essentially what I'm doing with my strawberries. The whole bed is made new each year. In the next week or so, I'll have to till up all the spaces that will be next year's rows of berries. New plants will set down, and this fall I'll rip out everything that is alive today. The newbies that are rather thin in September will bush out in April and May.

    I like your brother's idea about starting a whole new row so that I could put in some compost and manure. I think I didn't arrange my garden space well to do that. But I may have to consider trying it every few years.

    As for getting rid of 2/3 of the bed each year ... yup. Depending on how vigorous your new growth is, you'll eliminate 1/2 or 3/4 of the new growth (next year's bearing canes) -- and then all of this year's canes have to be chopped down after they bear.

  5. Thanks so much for all the discussion, here and on FB. I was reading lots of county-extension handouts but just was not picturing how things worked in real life!