How To Overwinter Blackberries

To overwinter blackberries, you need to protect the canes from freezing temperatures, drying winds, and winter stress so they come back strong in spring.
 
If you’re growing blackberries in a cold climate, overwintering blackberries is one of the most important steps for a healthy harvest.
 
Some varieties are hardier than others, but even tough blackberry plants benefit from a little winter protection.
 
The goal of overwintering blackberries is simple: keep the crowns and canes alive through the coldest months.
 
In this post, we’ll walk through how to overwinter blackberries step by step.
 
You’ll learn when to start, what to do for different growing systems, and how to avoid the mistakes that kill blackberry canes.
 
Let’s get your blackberries tucked in for winter.
 

How to Overwinter Blackberries

Overwintering blackberries works best when you prepare the plants before the first hard freeze.
 
Blackberries are perennial, but their canes are often the most vulnerable part of the plant in winter.
 
Cold temperatures alone aren’t the only danger; drying winds and alternate freezing and thawing can do real damage too.
 
When you overwinter blackberries properly, you protect the canes that will produce next year’s fruit.
 
Here’s how to do it:
 

1. Know Your Blackberry Type

Not all blackberries overwinter the same way.
 
Erect blackberries grow upright and are usually hardier, so overwintering blackberries of this type is simpler.
 
Trailing blackberries, like many thornless varieties, grow long canes that need to be laid down and covered.
 
If you’re unsure which type you have, check the tag or the nursery where you bought it.
 
Knowing this tells you whether you can leave canes standing or need to bend and bury them.
 

2. Stop Fertilizing in Late Summer

One of the easiest ways to help overwinter blackberries is to stop feeding them nitrogen in late summer.
 
Nitrogen pushes new growth, and tender new canes are the first to die in a freeze.
 
Let the plants harden off naturally as fall arrives.
 
This simple step makes overwintering blackberries much easier because the canes are tougher going into winter.
 

3. Prune After Dormancy

Wait until the plants are fully dormant to prune.
 
Remove spent floricanes (the canes that fruited this year) and any weak or damaged growth.
 
Pruning before overwintering blackberries reduces disease and makes the remaining canes easier to protect.
 
Don’t prune too early, though, because fresh cuts can invite winter injury.
 

4. Water Before the Ground Freezes

Dry soil freezes deeper and faster than moist soil.
 
Give your blackberries a deep watering before the ground freezes solid.
 
This helps the roots and crowns survive the cold and supports overwintering blackberries through dry winter spells.
 
Just don’t water so much that the soil stays soggy.
 

Overwintering Blackberries in Cold Climates

In cold climates, overwintering blackberries takes a bit more effort.
 
If you live where temperatures drop below 0°F, you’ll want to protect canes, not just roots.
 
Here are the methods that work best:
 

1. Lay Canes Down and Cover Them

For trailing blackberries, gently bend the canes to the ground in late fall.
 
Pin them down with landscape staples or weights.
 
Then cover them with straw, leaves, or a floating row cover.
 
This is the most reliable way of overwintering blackberries in very cold zones.
 

2. Mound Soil or Mulch Around the Crown

For erect blackberries, mound soil or mulch around the base of the plant.
 
A 4- to 6-inch mound protects the crown, which is the most important part for overwintering blackberries.
 
Even if the canes die back, a protected crown will send up new growth in spring.
 

3. Use Row Covers for Extra Protection

Floating row covers add a layer of insulation and block drying winds.
 
Drape them over the plants and secure the edges with soil or pins.
 
This is a simple trick for overwintering blackberries when you don’t want to bend canes.
 

4. Build a Windbreak

Wind can dry out canes even when temperatures aren’t extreme.
 
A simple windbreak made of burlap or a snow fence helps with overwintering blackberries by reducing moisture loss.
 
Place it on the side where winter winds usually hit.
 

Common Mistakes When Overwintering Blackberries

Even with good intentions, some mistakes can undo your work.
 
Here’s what to avoid when overwintering blackberries:
 

1. Pruning Too Early

Pruning in early fall stimulates growth that won’t harden off.
 
That new growth is the first to die, which hurts your chances of overwintering blackberries successfully.
 

2. Letting Canes Dry Out

Winter wind and sun can dry canes even in cold weather.
 
Mulch and covers help hold moisture, which is key for overwintering blackberries.
 

3. Removing Mulch Too Soon

Don’t pull mulch off the moment temperatures rise for a day or two.
 
Wait until the danger of hard frost has passed.
 
Rushing this step can ruin all your work overwintering blackberries.
 

4. Ignoring Variety Hardiness

Some blackberries simply aren’t built for extreme cold.
 
If you garden in a very cold zone, choose hardier varieties from the start.
 
That makes overwintering blackberries far less stressful.
 

So, How Do You Overwinter Blackberries?

You overwinter blackberries by protecting the canes and crowns from cold, wind, and drying out.
 
Stop fertilizing in late summer, prune after dormancy, water before the ground freezes, and cover or mound your plants.
 
In cold climates, lay canes down, use row covers, and build a windbreak.
 
Avoid pruning too early, letting canes dry out, or removing mulch too soon.
 
With these steps, overwintering blackberries becomes a simple routine that pays off with a bigger harvest next season.