It’s been a chilly start to New Year in 2024, but December of 2023 was the warmest ever for Western Washington! That means it’s not too late to do some winter garden work.

Winter is a great time to mulch, prune, and plan for your spring and summer endeavors:


Adding a layer of mulch to your garden beds is a great way to prep the soil for spring, and prevent water runoff during this rainy season.

When we experience a lot of rain, water can wash soil nutrients below the root zones where plants can no longer access them, or onto impervious surfaces and into drainage systems. Mulch slows the velocity of water flowing into the soil, keeps soil in place, and absorbs excess water. Plus – new mulch elevates the look of your garden beds!

We recommend installing a dark, fine mulch.


Most trees and shrubs go dormant during the winter, making late winter an opportune time to prune for the health of the plant.

  • It is easier to spot damaged and dead branches once the leaves have dropped from deciduous varieties.
  • Pruning in the late summer and fall can stimulate new growth that may not survive the colder months. Making cuts during the dormant period removes that risk.
  • Plants hold energy and nutrients in their roots during the winter, which allows them to heal their wounds quicker and regrow healthy foliage faster in the spring.
  • Research shows that pruning done before buds begin to show leads to optimum wound closure, since diseases and pests are less active in the winter.

Note: These are generalities, we always recommend looking up the pruning techniques best suited for each individual specimen in your garden. If you have an early spring blooming shrub or trees, winter pruning will not harm the health of the plant but may diminish the number of blooms. It is recommended to delay pruning those until after the last flowers drop.

Have a large tree you need to prune?

Seattle requires you to work with a licensed arborist to prune anything above 15 feet. We recommend working with our friends at a local company like Seattle Tree Care or Bartlett Tree Experts.


Spent flower heads from last summer are full of seeds. To help your herbaceous perennials spread faster, you can sprinkle the seeds around the existing plant, or save them to sow in the spring. 

Several of our team members sow their harvested seeds indoors during the early spring for both flowers and food varieties, to be transplanted outdoors in the garden after the last threat of frost!


Herbaceous perennials die back in the late fall and winter, leaving dry brown plant material behind. You can cut these dead parts back to the base of the plant to encourage new, vigorous healthy growth in the spring.

“I’m not dead yet”

– Monty Python and the Holy Grail (or your perennials, maybe)

Often when our team does perennial planting projects for our clients in the winter, it can seem almost comical to place what seems to be a dead plant. The plant may look worse for wear, but fear not! The healthy roots will spread and get established over the winter to regenerate gorgeous greenery and blooms in the warmer months.

When freezing temperatures are on the way, you can protect your garden plants by giving them a deep watering. It sounds counterintuitive, but the extra water will provide insulation for roots since wet soil stays warmer than dry soil.

Water holds heat

It’s the reason why the oceans play a major role in climate (and the slowing of climate change – next time you’re by the ocean, dip your toe in and say thank you). Water releases heat as it cools, and this heat can prevent the water in plant tissues from freezing. Because we typically don’t see extended periods (more than a week) of below freezing temps in the temperate Seattle region, a little extra water in the soil can truly help protect your plants.

If you want to provide an extra layer of protection to your garden during more extreme freezes, you can also cover your favorite specimens with old moving blankets, towels, burlap, or other recycled fabrics during the worst of the freezing temperatures. Do not do this for long periods of time! Remember that even in the winter, plants need the sun to regulate and photosynthesize.


A fun activity to do during the winter is think about what you want to do in the garden when the warmer weather of spring and summer returns! Plan out new things you want to plant, a garden refresh, trying your hand at growing food, or starting a new hobby with your garden plants.

You can also create hardscapes like raised beds, patios, retaining walls, and fences in the winter to be ready for spring planting. Thinking about in-ground irrigation? This is the best time of year to dig up your yard or lawn, rather than when you want to be out enjoying it.

Design Now for a Productive Season

Our team stays busy all winter creating designs with clients for spring plant installations. Whether you work with a professional or not, winter is the best time to plan out what you want so you can get right to work planting at the optimal times for each species.


Getting outside in the winter has so many benefits to physical and mental health. As long as you are dressed for the weather, you can enjoy a winter day in your garden just as much as a summer day. We are lucky to have four distinct seasons in the PNW, and one of the great joys of living in such a place is getting outside to experience them all!

Get to know the Nordic custom of “friluftsliv,” which translates to “open air living” and encourages the commitment to celebrating and getting outside no matter what the weather forecast looks like. 

Can’t pronounce friluftsliv, or simply not as excited about winter garden work?

Seattle Sustainable Landscapes can help you accomplish your winter garden care. Contact us to get a quote for mulch, winter cleanups, pruning, and garden design!