Tending to a garden is an intimate look into nature's patterns, from the sweltering summer highs to blissful seasonal rains. Year after year, we watch for the first spring blooms and eagerly await when the days are warm enough to plant tomatoes. We keep a close eye on the weather to tell us when to plant, when to prune, and when to ratchet up the watering for the summer. As careful observers of these seasonal cycles, it's no surprise that many gardeners are starting to notice the effects of climate change first-hand.
As a Portland-based nursery for nearly 40 years, we're keenly aware of how Oregon is changing and the ways it's impacting our community. If climate change is weighing heavy on your mind, you might be anxious to know what to expect and how you can future-proof your garden against unpredictable conditions. Even as we navigate a changing climate, plants present a world of opportunity: your garden has the power to become a tool of adaptation and resilience in these uncertain times.
How Climate Change is Impacting Oregon
Everyday weather is ephemeral and unpredictable, but our climate is represented by long-term trends that we can come to expect each year. Historically, Northwest Oregon has been known for its cool, wet winters and warm but mild summers. Already, many of us are noticing this norm begin to change: the Oregon Climate Change Research Institute at OSU reports that, so far, almost every year of the 21st century has been far drier and hotter than the norm.
Rising Temperatures
Across the state, average temperatures have increased 2.2º F since record-keeping began in 1895; by 2100, temps could rise up to 7.6° F. This can bump certain areas up an entire USDA hardiness zone, quickly changing which plants are suitable for growing in your area.
Changing Precipitation Patterns
The trend of hotter, drier summers is here to stay as our precipitation patterns shift to less frequent yet higher intensity rainfall events (i.e. atmospheric rivers). This new cycle presents higher risks of both summer drought and cool-season flooding.
Extreme Weather Events
Hazardous weather is one of the most damaging and unpredictable features of Oregon's climate future, from intense winter storms to temperatures over 115ºF during 2021's deadly 'Heat Dome.'
How Can We Respond?
The changing climate can be an overwhelming, stressful, and controversial topic to contend with, but gardening is always an act of experimentation. When so much of this issue is out of our individual control, helping our plants survive — and even fight climate change — is an empowering way to engage with the reality our planet is facing.
Water Smart
Water is a precious resource in a changing climate. Plants need water to survive, but they also play a major role in the water cycle by absorbing moisture into their tissues and holding soil together, reducing flooding and erosion.
- Water in the morning or evening when the ground is cool so that moisture absorbs into the soil rather than evaporating
- Prioritize thoroughness over frequency when you water to help your perennials, trees, and shrubs to develop robust root systems that reach deeper into the soil
- Retain moisture in the soil by amending with organic matter like compost, then topping the soil with a layer of mulch
- Plant perennials and/or cover-crops to avoid bare, exposed soil
- Hydrate your soil with a rain garden
- Instead of letting rainfall flow out out of your garden and into stormwater drains, keep that valuable moisture on-site by creating a swale or rain garden — a porous depression in the ground that collects and absorbs water, often planted with moisture-loving plants. You can even set up your home's downspouts to feed these features, redirecting runoff from your roof to hydrate the water table deep within your soil. For more information about making the most of rainfall, see our article on Creating a Rain Garden.
- Choose plants that need less irrigation
- Drought-tolerant plants can still provide impressive color, form, and ecological benefits like attracting pollinators — all with minimal irrigation. For more information about growing drought-tolerant plants, see our article on Creating a Water Wise Garden.
Create Shade
Gardening can be a delicate balance between making sure your plants get enough light and minimizing their exposure to the most intense of the sun's rays. With summer temperatures predicted to continue rising, establishing shade can be a life-saver for both you and your plants.
Natural Shade
Trees offer substantial natural cooling benefits by shielding your home and garden from the sun. Tree canopy has a huge impact on summer temperatures. In areas with lots of pavement and few green spaces, the 'Urban Heat Island Effect' can leave your neighborhood over 10º F hotter than surrounding areas with more trees. If you live in the Portland Metro or another urban area, the National Tree Equity Explorer is an interactive tool you can use to see how tree cover (or lack thereof) affects temperatures near your home. Planting more street trees is a great way to cultivate cooling relief — our blog post on the topic offers tips and local resources for street tree planting.
Layering plants is another beneficial design tactic for a climate-resilient landscape. Trees offer the largest canopies, while a well-placed shrubs can offer protection for annuals and perennials. Like mulch, groundcovers act as a barrier that prevents the soil beneath from drying out.
Get Creative with Shade
One way we're adapting to intensifying summer heat is installing new shade structures to protect plants like part-sun perennials and conifers. Awnings, pergolas, and shade cloths are great ways to reduce direct sunlight during hot summer days, both for you and your plants.
Set Your Plants Up for Success
Avoid stress by making sure you're providing the right light and water conditions to help each plant thrive. It may take some trial-and-error to find the balance of 'Right Plant, Right Place,' but plants are remarkably resilient — and so are gardeners. Adaptation may mean choosing new-to-you varieties to conserve water or finding new ways to support your old favorites. Embracing creativity and experimentation will help us all meet this unprecedented moment.
The best time to plant trees and shrubs is usually fall through early spring, where the ground is soft and moist from the seasonal rains. This gives plants a chance to get established by focusing on their root systems before the growing season. Since the spring and summer are often the most active gardening season, though, it's a natural time to want to plant. Make sure to keep establishing plants thoroughly watered, especially during the warmer months. We always recommend amending the soil with E.B. Stone's Sure Start at planting time to avoid transplant stress and spreading mulch around the root ball to preserve moisture.
Gardening as Climate Action
While so much of the action needed to address climate change must take place on a systemic level, your garden is one space where you can make a direct and powerful difference. Adapting your garden for the future is more than a way to keep your plants happy — it's a strategy that can help make your entire neighborhood more resilient to these changes.
Cultivating shade trees lowers record-breaking air temperatures and stores carbon. Plants help reduce the erosion and flooding risks that are projected to increase; they can even help reduce fire risks. In times of uncertainty for our wider ecosystems, growing a garden offers a refuge for biodiversity and engages you with the cycles of a changing world. Perhaps best of all, gardening gives you actionable ways to prepare yourself for the challenges of climate change and create a positive impact the environment around you.
For more resources about Oregon's changing climate, the OSU Extension's new Garden Future resources are designed specifically for helping gardeners navigate these changes. We also recommend digging into our other posts about Water Wise and Firewise gardening, both of which include tips and plant lists for adopting these strategies at home. If you have any questions about climate preparedness, our knowledgeable team is here to help you garden for the future.
