David Handley: I’m David Handley with the
University of Maine Cooperative Extension. And today, we’re going to talk about pruning
raspberries. Now, the proper time to prune raspberries is really any time after they
go dormant. So, this can happen at any time from November right through March. Personally,
I prefer to do it in the late winter/early spring in March. This is because as the older
canes are dying, they’re sending sugars and carbohydrates and nutrients back down to the
root system, which will help next year’s canes get through the winter.
Now, when we’re pruning raspberries, we’re looking to accomplish three things. We can
do them at the same time, but I’ll lay them out for you. The first is that we’re going
to narrow up the row because every year the raspberries rows tend to get wider and wider.
And you want to narrow that row up to about two feet to about one and a half feet wide.
The second thing we want to do is get rid of all of the canes that fruited last year.
These are called spent floricanes fruiting canes that have already fruited. These canes
are dead. They’re just getting in the way and taking up space. So, all of those are
going to come out. Then, the final thing we’re going to do is
thin the remaining canes such that there’s only three or four canes per linear foot.
OK. So, this is going to look very thin when we’re all done. And we’re going to be taking
up the majority of the canes that you see here now.
As you approach the planting, you’ll notice there are really three kinds of canes that
you’re dealing with. First, are those spent floricanes that we talked about. These have
gray peeling bark. And they also have these remains of little branches on them that we
call the fruiting laterals. Any cane that’s showing this gray peeling bark and has these
old fruiting shoots on them should come out. These canes are dead anyway. When you cut
into them, you’ll see there’s nothing but brown wood in there. There’s no green tissue,
living tissue, at all. All of these come out. The next type of cane you’ll run into are
a lot of weak spindly canes, very thin, very short, they don’t reach the trellis wires,
which we’ll see in a minute. These just aren’t going to produce very good fruit. If they’re
thin and short like this, all of these should come out as well.
Finally, and hopefully, we’re going to have a good selection of nice thick fruiting canes.
These, if you peel the bark back a little bit, you’ll see they have green shoots. You’ll
notice that instead of the shooting laterals that we saw in the spent floricanes, these
just have buds. Now, in the springtime, these buds are going to break and give us fruiting
shoots. And that’s our crop for that next year.
So, this is what we want to keep. And we want to look for the thickest basal diameter, in
other words, the thickest stems and good height, OK, so that they’ll reach the trellis wire
and we can attach them. So, these are the ones we want to save as long as they are within
that two foot width perimeter that we’ve set up for ourselves.
Now, you can see here, here’s a raspberry row. This variety happens to be Boyne, one
of my favorite varieties. And you can see the row width here has gone out to three,
even four feet, even though we started with a row that was only a couple of feet wide.
And that’s because the new shoots, as they came up during the summer were looking for
light and less competition. So, they’re getting here. We don’t want them.
If we allow these canes to go ahead and leaf out next year, they’re going to be shading
out all the canes in the middle. And I’ll have lots of fruit rot problems. And I won’t
want to have to reach in there through all these thorny canes to harvest that fruit.
So, I’ll loose a lot of it. So, initially, using some nice, sharp loppers,
and some good thick gloves, because these are thorny and I always like to wear safety
glasses because these are thorns and they’re sticks running around your face all over the
place, we can get started just cutting them right at the base. And, as you’re cutting,
you can just pull those canes that you’ve cut out of the way, throw them into the row,
middle, so that you can collect them later. We’re not going to leave these behind because
these can be a source of disease problems for us next year. So, everything we’ve cut
out, when we’re all done, is going to be dragged out of here and either chopped up and put
into the compost pile, or burned, or taken to the local dump, but not left here.
OK. Now, that we’ve got this row pruned, you can see how narrow the base is. We’re trying
to keep that row width at the base about to a foot and a half to two feet wide. And then,
you can see our trellis wires at about four feet, are spread to about three and a half
feet wide. And what we’re going to do with the nice canes that we left behind is attach
them to this trellis wire. Now, what you use to attach them is really
whatever works best for you. Old bread twist ties work pretty well, just take that cane,
wrap the twist tie around it, and get it on fairly tight so that the wind is not going
to be able to blow it around too much. There are some other things you can buy that
have recently become popular here, some little rubber bands with a little T on the end of
them that can be used. And, in this case, you just grab it. Bring the rubber band around.
And that little T just grabs the other end of the rubber band. So, that holds fairly
well. It works better on thicker canes. If you’re a home gardener and like to grow
vegetables, you’re probably familiar with different types of tomato clips. These are
just little plastic rings that you can use to clip plants on. And these will also work
fairly well. We just take a cane, clip both the wire and the cane and leave it there.
And that’s just so that the cane can’t be allowed to bounce back into the middle.
And also, we have machines that’ll do this for you. These are called tapeners. And, in
this case, you just grab the cane and you put a little piece of plastic over it. And
it works like a staple gun. You just grab that, and then a staple clips it, releases
it, and gives you a little piece that holds on to the cane pretty well there. These are
fast and relatively efficient, but you have to buy a lot of tape and a lot of staples
for them. And, because they’re plastic, they will be here for a long time. Remember, we’re
going to take these off next year after these canes are fruited because we’ll be pruning
them out. And you’ll have lots of little bits of plastic to deal with.
So, one way to get around that is to use the old fashioned method which is just using some
bailing twine or cotton string, whatever is available to you, and just taking the cane,
spreading them to the wire, and just giving them a simple knot, either a slip knot or
a granny knot or a square knot, anything works pretty well just grab both the cane and the
trellis wire. And what I like about these is that you can get it fairly tight. It’s
fast if you fill your pocket full of little bits of string cut to eight or 10 inches.
And then, next year, when I’m going to prune this out, I can just clip this off with a
pair of scissors and it will fall to the ground. It will bio degrade. I don’t have to worry
about plastic all over the place. Now, the idea here is we’re going to attach
all of these to the trellis wire to spread these canes out such that, here, we’re going
to have them spread out to three feet at the base or a foot and a half. When, we’re all
done, we should have a nice V effect that’s going to allow the sun to come down and provide
plenty of light and air movement through this planting to make sure that we’re not going
to have a lot of disease problems. The other thing this is going to do is put
all of our fruiting canes on the outside. And then, our new canes that’ll fruit next
year are going to be coming up in the middle where we want them, and we won’t have to fight
our way through those thorny primocanes to get to our fruiting canes. So, let’s tie these
up and take a good look at what the finished product should look like.
You can see we finished pruning. We’ve left only the primocanes from last year. We’ve
taken out all those dead floricanes. We’ve removed all the scrawny growth. We’ve narrowed
up the base of the plant so that, the row planting, so we’re only about two feet wide
at the base and we spread them out to about three feet up towards the tops of the canes.
So, if you look down the row, you see we have this lovely V effect. And that’s just what
you want to see in a raspberry planting. Now, I like to leave the tops on. Some people
like to ask, shouldn’t I tip the raspberry planting and cut the tips off? Well, the fact
is that if you do that, you’re cutting off all these buds that are going to be fruiting
laterals for you next year. If your canes are so tall that you’re not going to be able
to reach them, when they’re going to bend over the wire, you can trim back a little
bit. Just remember this rule of thumb, if you cut off more than 25 percent of the cane
tip, you’re seriously reducing your yield. So our planting is good to go. We’re all set
for the winter. And we’re going to have a real good crop on this for next year, and
we’ll be ready to set up for a good summer of raspberries.