Pruning Your Dormant Blackberries & Raspberries

As winter blankets the garden in stillness, it may seem like a time when the world of plants takes a much-needed break from its vibrant summer activity. However, for those who grow cane berries like raspberries and blackberries, this season of dormancy is a critical juncture in the yearly cycle. In this comprehensive guide, we will delve into the intriguing world of pruning dormant cane berries and understand why this period is so vital for the health and productivity of these beloved berry plants.

The Dormant Season: Nature's Slumber and Plant Rejuvenation

Dormancy is a natural state that many perennial plants, including cane berries, enter into during the colder months of the year. It's a phase when growth appears to halt, leaves fall, and the plant's energy is redirected inward, focusing on root development and energy storage. This temporary suspension of active growth serves multiple purposes in the plant world.

Why Prune During Dormancy?

So, why is it crucial to prune cane berries during this period of dormancy? The answer lies in the unique growth patterns and life cycles of these berry-producing plants.

Raspberries

Let's begin with raspberries. Raspberry canes exhibit a biennial growth cycle. In the first year, they are known as "primocanes" and do not bear fruit. However, in their second year, they transform into "floricanes," producing the succulent berries we eagerly anticipate. But here's the catch: once these second-year canes have borne fruit, their journey comes to an end. They begin to wither and will no longer produce berries.

This is where winter pruning comes into play. By the time the dormant season arrives, these spent canes are ready to be removed. They've given their all in producing a delectable harvest, and now it's time to make room for new growth. Cutting back these dead, damaged, or weak canes right at ground level not only tidies up your raspberry patch but also eliminates potential disease sources and encourages the emergence of vigorous, fruit-bearing canes in the coming year.

But winter pruning isn't just about removing the old; it's also about nurturing the new. During dormancy, it's easier to identify the robust canes, typically around 1/4” in diameter, that will bear fruit in the next season. Thinning out these canes, leaving them spaced about 6” apart, allows for better air circulation and sunlight penetration, fostering healthier berries. As you trim away the excess growth, you're effectively sculpting your raspberry patch for future abundance.

Raspberry Patch Management

One of the peculiarities of raspberries is their propensity to spread through underground runners, creating an ever-expanding berry patch. Left unchecked, your raspberry patch could become an unruly jungle. This is where diligent pruning during dormancy also comes to the rescue.

By digging up any raspberry plants that have ventured beyond the 2’ wide row you aim to maintain, you not only maintain order but also create opportunities. These rogue plants can be relocated to other parts of your garden, shared with friends eager to start their own berry adventure, or repurposed in your compost bin, ensuring that your raspberry patch remains a controlled and productive oasis.

Blackberries

Unlike raspberries, blackberries exhibit a range of growth habits—erect, semi-erect, and trailing. Each type demands its unique set of pruning techniques, all of which are most effectively applied during the dormant season.

1. Erect Blackberries: Erect blackberries, true to their name, grow upright and are often easier to manage. Pruning these blackberries during dormancy involves several key steps:

• Removal of dead canes, typically identified by their brown color, should be a priority. These canes have served their purpose and will no longer contribute to the plant's vitality.
• Trimming back the laterals, or side branches, to a length of 12–18” encourages fresh growth and ensures a more compact and manageable plant.
• If the canes have grown taller than your trellis or fence, topping them to about 5’ not only keeps them in check but also simplifies future maintenance.

2. Semi-Erect Blackberries: Semi-erect blackberries possess characteristics of both erect and trailing varieties, demanding a unique approach to pruning. Here's how to care for them during dormancy:

• Thinning out the canes is essential. Keep 5 to 8 of the strongest ones, removing the weaker ones to allow the remaining canes to flourish.
• Shorten the laterals to a length of 12–18” to stimulate new growth and promote a bushier, healthier plant.
• Focus on the lower 3’ section of the main canes, removing any growth in this area to encourage upward growth.
• To provide support, consider tying these semi-erect canes to a fence or trellis, preventing them from sprawling and making harvest more accessible.

3. Trailing Blackberries: Trailing blackberries, while rewarding, require special attention, especially in colder regions. Dormant pruning for these varieties is an art in itself:

• In regions with harsh winters, leave the canes on the ground during dormancy.
• Protect them by covering them with row cover or mulch to shield them from the elements.
• In the spring, when the threat of frost has passed, lift the canes and tie them to a trellis at heights of 3’ and 6’. This encourages vertical growth and prevents the canes from sprawling on the ground, simplifying future maintenance and harvest.

Final Thoughts on Pruning Dormant Cane Berries

By understanding the unique growth patterns of raspberries and the diverse habits of blackberries, we can unravel the secrets of effective pruning during the dormant season. Pruning during this time allows us to remove spent canes, paving the way for fresh growth and a bountiful harvest. It's a time when we sculpt our berry patches, maintaining order and ensuring that these delectable fruits have the space and resources they need to thrive.

The dormant season is nature's gift to gardeners, providing an opportunity to rejuvenate and prepare for the vibrant growth that awaits in the seasons to come. So, embrace this season of rest, and with mindful pruning, watch your dormant cane berries awaken to a fruitful and flourishing future. Happy pruning!

Additional Resources

We have a wide variety of berry plants for sale.

Our resource center includes How to Grow Cane Berries: A Growing Guide.

Follow these tips from Master Gardeners in your region.

1. Napa Master Gardener Column - UC Master Gardeners of Napa County: This article provides a comprehensive guide on pruning various types of raspberries, including summer-bearing, fall-bearing, black, and purple raspberries. It also covers the specifics of pruning blackberries and offers tips for maintaining a healthy berry patch. For more details, visit UC Master Gardeners of Napa County.

2. Berry pruning basics - OSU Extension Service: This resource from the Oregon State University Extension Service covers the basics of pruning fall-bearing raspberries, black and purple raspberries, and blueberries. It includes instructions for pruning during the dormant season and the growing season, along with tips for maintaining healthy currant and gooseberry bushes. To read more, visit OSU Extension Service.

3. Berry Good to Prune Your Berries Properly - UC Master Gardener Program of Contra Costa: This article focuses on the correct pruning techniques for blackberries. It explains the difference between primocanes and floricanes and offers advice on how much to prune each type. Additional resources on blackberry care are also provided. For further information, check out UC Master Gardener Program of Contra Costa.

4. Pruning: Fruit Trees and Blueberries - Buncombe County Extension Master Gardener Volunteers: This piece provides a detailed guide on pruning blueberries for maximum yield and health. It includes specific steps for pruning at various stages of a blueberry bush's life, from initial planting to established plants. The article emphasizes the importance of thinning and heading back to promote healthy growth. You can learn more at Buncombe County Extension Master Gardener Volunteers.

5. Winter pruning boosts blackberry and raspberry harvests - Illinois Extension, University of Illinois: This article highlights the benefits of winter pruning for blackberries and raspberries. It describes the different needs of everbearing plants, erect brambles, and semi-erect brambles. The article also offers tips for pruning at spring planting and managing root suckers and hills. More details are available at Illinois Extension.