Pruning in Late Winter: Supporting Native Plants, Healthy Landscapes, and Native Bees

As winter begins to transition toward spring, late winter remains one of the most important times to prune trees, shrubs, and perennials across Clark County. While pruning has long been recommended for plant health and structure, research from Washington State University (WSU) Extension and Oregon State University (OSU) Extension also highlights how thoughtful pruning can support wildlife habitat — especially native bees.

When plants are dormant, pruning is easier and less stressful for the plant. Without leaves, gardeners can clearly see branch structure, remove damaged or crossing branches, and guide healthy growth before spring begins.

But pruning isn’t just about aesthetics — it’s also an opportunity to intentionally create habitat.

Pruning Doesn’t Mean Total Cleanup: Messiness Is Habitat

While late winter pruning is an important step for plant health, it’s equally important to remember that pruning does not mean removing every leaf, stem, or piece of organic material from your garden. A certain level of “messiness” is not only acceptable — it’s essential for supporting native insects and overall biodiversity.

Leaf litter plays a critical role in the life cycles of many beneficial species. Bumble bees often overwinter in or beneath soil protected by layers of leaves, while moths and butterflies may overwinter as eggs, caterpillars, pupae, or adults hidden within leaf litter and garden debris. Removing all fallen leaves too early in the season can unintentionally eliminate important habitat.

Similarly, when cutting back forbs and herbaceous plants, consider leaving both standing stems and some of the pruned material on site. Stems and plant debris can shelter insects that are overwintering inside or attached to plant material. Leaving pruned stems in place — even temporarily — gives emerging insects time to complete their life cycles and disperse naturally as temperatures warm.

A pollinator-friendly approach focuses on balance: thoughtful pruning paired with intentional habitat retention. Leaving some leaves, stems, and natural debris helps create a resilient garden that supports wildlife year-round.

A Clark County Native Plant Approach to Pruning Woody Shrubs

Many of our region’s native shrubs benefit from selective late-winter pruning. Instead of shearing plants into tight shapes, extension resources recommend removing older or damaged stems and encouraging natural structure.

Native woody shrubs common in Clark County landscapes include:

• Oregon grape (Mahonia spp.)

• Oceanspray (Holodiscus discolor)

• Red-flowering currant (Ribes sanguineum)

• Mockorange (Philadelphus lewisii)

• Native honeysuckle (Lonicera spp.)

• Serviceberry (Amelanchier alnifolia)

• Elderberry (Sambucus spp.)

General pruning principles from WSU and OSU Extension include:

• Remove dead, diseased, or crossing branches first.

• Thin selectively rather than cutting everything back uniformly.

• Maintain the natural growth form of the plant rather than forcing rigid shapes.

• For spring-flowering shrubs, heavy pruning is often best done after bloom if you want to preserve flowers.

For native shrubs, consider pruning as a way to create layered habitat rather than purely visual uniformity.

Leave Some Stems: Habitat for Native Bees

One of the most important ecological updates to traditional pruning practices is leaving sections of stems for cavity-nesting native bees.

OSU Extension recommends leaving portions of cut stems — especially those with pithy or hollow centers — because native bees may use them as nesting sites.

For forbs and herbaceous perennials:

When cutting back plants such as:

• Yarrow

• Gumweed

• Asters

• Coneflowers and other sturdy-stemmed plants

Leave approximately 12–18 inches of stem whenever possible. These standing stems can provide nesting habitat for small native bees throughout the growing season.

For woody shrubs:

Avoid removing all dead or hollow stems. Some cavity-nesting species — including tiny Ceratina (small carpenter bees) — will nest inside elderberry stems and other hollow woody material.

A slightly “messier” garden can actually be a healthier ecosystem.

Trees in Late Winter: Maples, Oaks, and Structural Pruning

Late winter is also a good time to evaluate many deciduous trees.

According to extension guidance:

• Dormant pruning allows wounds to close faster and encourages strong spring growth.

• Removing structural defects early prevents larger problems later.

• Prune for structure — not size reduction or “topping,” which damages trees.

In Clark County landscapes, this may include:

• Bigleaf maple and vine maple

• Oregon white oak

• Other native or ornamental deciduous trees

Focus on:

• Removing dead or rubbing branches

• Improving airflow and light penetration

• Maintaining strong branch spacing

(Always research species-specific timing — for example, flowering trees may be pruned after bloom if flowers are a priority.)

Practical Strategies for Pollinator-Friendly Pruning

• Leave some dead wood or hollow stems whenever safe to do so.

• Create vertical structure by leaving standing stems rather than cutting everything to ground level.

• Combine aesthetics and habitat — tidy edges with ecological interiors often work best in neighborhood settings.

• Remember that pollinator habitat includes nesting areas, not just flowers.

Keep Your Garden Safe: Clean and Sharp Tools Matter

Pruning is also about preventing disease spread.

Extension recommendations include:

• Clean tools between plants using rubbing alcohol or a dilute bleach solution.

• Remove soil and debris from blades.

• Keep tools sharp to make clean cuts that heal faster.

• Lightly oil tools after cleaning to prevent rust.

• Sanitizing tools helps prevent pathogens from moving between plants and reduces the risk of long-term damage.

A Balanced Approach

Late winter pruning sets the stage for healthy growth, but it also offers a chance to support local biodiversity. By combining science-based pruning practices with habitat-aware strategies — like leaving stems for nesting bees — gardeners can create landscapes that are both beautiful and ecologically functional.

A little intention now can mean healthier plants, stronger ecosystems, and more native pollinators throughout the growing season.