Choose plants for hotter, drier summers

As our summers grow hotter and drier, we need to look carefully at the plants we choose for our landscape. Plants that do well in drought conditions are likely to be more successful with less work.

How has summer weather changed? 

Seattle’s summers have warmed significantly over the last decade. According to Seattle Met, “Seattle summers have warmed more in the past 10 years (2.2 degrees) than in the preceding 40 years (1.6 degrees). The net result of all this drastic warmth is that the ‘hot’ summers of yesteryear are cool summers by today’s standards.”

NASA found that summer 2024 was the hottest globally than any other summer in NASA’s record — narrowly topping the record just set in 2023. “Summer of 2024 was 2.25 F (1.25 C) warmer than the average summer between 1951 and 1980, and August alone was 2.34 F (1.3 C) warmer than average,” NASA’s Explore reported.

Summers tend to be drier too. Six of the last 10 years have brought some form of drought to the state. The Department of Ecology has issued a drought advisory for 2025 for watersheds in Pierce, King, Snohomish, Skagit and Whatcom counties, along with Okanogan and Chelan counties in north-central Washington. Ecology also listed a drought emergency for southern-central Washington (Kittitas and Yakima Counties).

So what’s a gardener to do?

Choose drought-tolerant plants

Fortunately there are many beautiful plants that need less water and grow well in Pacific Northwest conditions. Here are some of our favorite sources.

• Plants that are drought tolerant, Great Plant Picks
• Drought tolerant plants for the Pacific Northwest, Natural Yard Care Program
• Incorporating Pacific Northwest native plants into your water-wise landscapes, OSU Extension Service
• 19 drought-tolerant trees and shrubs for a waterwise garden, Swansons Nursery
• Drought-tolerant shrubs for the Northwest, Fine Gardening

Water smarter

“Drought-tolerant” does not mean you can plant and forget. Everything that is newly planted will need regular water until it is established, usually two growing seasons. And all plants will need some supplemental water during extended drought seasons; drought-tolerant plants will need less water than other plants.

You can save water in your landscape, while keeping your plants healthy, by watering efficiently. Our YouTube playlist, Watering your lawn and garden, contains 13 videos to help make your watering more efficient and effective. We have also written many blog posts on watering and drought. Here are links to a few:

• Lawn and landscape watering: 8 quick tips
• Smart watering: how much, when and how long to water
• Summer lawn care: watering, mowing
• Plants need water to survive and thrive
• Watering will help manage insect problems
• Invest in watering for landscape dividends

There are a number of other great resources for managing a garden and landscape in drought conditions. Here are some we recommend:

• Drought tolerant landscaping for Washington state, WSU Extension
• The truth about “drought-tolerant” plants, Swansons Nursery
• Drought-tolerant plants for the Pacific Northwest, plus other hot-weather gardening tips, Oregon Live
• Protect plants from drought, KING5

Improve your soil

Improve your soil by adding compost and organic mulch. Soil-dwelling organisms will break these supplements down, improving soil texture and making nutrients available to your plants. Healthy soil will make your landscape more resilient, so hot and dry conditions will have less impact.

Mulch is one of the best things you can do for your landscape. A thick layer (3-4 inches) of organic mulch, such as arborist chips, leaves or bark, reduces plants’ water needs and helps to keep soil from drying out, thus reducing the potential for drought stress. We recommend applying mulch annually.

Ciscoe Morris says that research shows having mulch over the soil profile in summer can keep the soil temperature at 75 degrees, even when the air temperature is 90 degrees. This is a huge difference in keeping the root system functioning properly. Mulch also greatly reduces weeds and feeds your plants.

See our blog posts, How to use mulch in your yard and Pro tips on how to mulch.

We can help

We can help you create a drought-tolerant landscape. Contact us for help with sustainable landscape design and installation and for natural lawn, tree and shrub care services, such as applying compost tea and mulch.