How to Prepare Boysenberry Bushes for Winter

Boysenberries, Rubus ursinus x R. idaeus, are tasty hybrid berries that typically grow best in USDA Hardiness Zones 5-9.

I’m in Zone 4, and it is admittedly audacious of me to to grow them here. But what’s the fun of gardening without a challenge?

Fortunately, with adequate winter care, my boysenberries produce a delicious harvest year after year.

In our guide to growing boysenberries, we cover how to cultivate these shrubs in your garden.

If you’re growing this tasty berry in Zones 4-7, you’ll need to do a few things to prepare it for the winter.

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In this guide, I’ll share everything you need to know.

Here’s what we’ll cover:

Here in Alaska, wild roses fill my yard with tender pink blooms every spring, and plump rose hips in midsummer and early fall.

Since boysenberries are members of the rose family, you’d think they might do okay in Alaska’s cold climate.

Raspberries grow prolifically here, too, and boysenberries are a hybrid of blackberries, raspberries, loganberries, and dewberries.

But here’s the thing: Rubus ursinus x R. idaeus is a rare hybrid that nearly failed to thrive altogether as a species early in its history. 

It requires full sun, organically rich soil that’s also loose and well-draining, and protection from a variety of diseases and predators.

It can withstand some frost, but only if that frost comes after the plant has had a chance to realize that the days are growing shorter and cooler, activating cold acclimation in the plant.

For boysenberries, acclimation can only take them so far.

Here’s how to help them stay warm and