Tip Sheet #3: New to Gardening in Western Washington

Have a New Home? 

Get acquainted with your landscape. Make a sketch of the yard and label all the plants you can identify. If you can, ask the seller about plants you don’t recognize. Note which areas get sun or shade. To help you remember plants in the future, set up a folder labeled “plant tags.” As you buy plants, just put the tag that describes them into the folder. You may not want to make major changes the first year. Instead, update your sketch as the seasons change. You may find plants emerging that you didn’t know were there. 

Call Before You Dig 

If you plan to dig more than 12 inches underground, Washington law requires you to have utility lines located and marked so they won’t be damaged. Call 811 two business days before you dig. Once utility lines are located (a free service), mark them on the landscape sketch you made. 

Choose the Right Plants 

Stay “In the Zone” 

The U.S. Department of Agriculture (USDA) maps the country into hardiness zones based on average lowest winter temperature: 2023 USDA Plant Hardiness Zone.  Their 2023 update categorizes most of Port Townsend as 8b (15 to 20 °F/-9.4 to -6.7 °C), with some small areas classified as 9a (20 to 25 °F/-6.7 to -3.9 °C (mostly located along the water in NE Port Townsend, northern Marrowstone and scattered areas around DIsco Bay). First and last frost dates vary with elevation as well as location (proximity to bodies of water, rainshadow effect, etc) 

Port Townsend, WA (Jefferson county)

Temp 10%20%30%40%50%60%70%80%90%
Spring 32° Mar 28Mar 18Mar 10Mar 2Feb 25Feb 19Feb 12Feb 4Jan 24
Spring 28° Mar 2Feb 19Feb 12Feb 5Jan 29Jan 23Jan 15Jan 5N/A
Fall 32° Oct 31Nov 9Nov 16Nov 22Nov 27Dec 3Dec 9Dec 16Dec 25
Fall 28° Nov 15Nov 26Dec 5Dec 13Dec 20Dec 27Jan 5Jan 16N/A
Port Townsend WA, Chance of Frost Dates for specific temperatures in Spring and Fall

Quilcene, WA (Jefferson county)

Temp 10%20%30%40%50%60%70%80%90%
Spring 32° May 6Apr 23Apr 14Apr 7Mar 30Mar 23Mar 15Mar 6Feb 21
Spring 28° Apr 3Mar 20Mar 9Feb 28Feb 19Feb 11Feb 1Jan 21Jan 3
Fall 32° Oct 18Oct 26Oct 31Nov 5Nov 10Nov 14Nov 19Nov 25Dec 5
Fall 28° Nov 7Nov 17Nov 24Nov 29Dec 6Dec 12Dec 18Dec 25Jan 5
Quilcene WA, Chance of Frost Dates for specific temperatures in Spring and Fall

Finding your zone 

If you are not sure of your zone, enter your zip code at the USDA site, ask a nearby nursery or Master Gardener clinic. Nursery plant labels will usually indicate zone hardiness. You can go lower than the zone you are in but you should not go higher.  For example, if you are in zone 8 you can use plants labeled for zone 7 or below.  Plants that thrive in the higher zones are not cold-hardy and will not survive our winters. Throughout Western Washington, varied topography gives rise to many microclimates — areas where local conditions may differ from those of the surrounding climate zone. WSU publication FS181E, “How to Determine Your Garden Microclimate,” is available free at pubs.extension.wsu.edu and can help gardeners understand their unique growing conditions.  

Pay attention to Sun and Shade

Plant labels will also indicate the plant’s light requirements. 

  • Sun: at least 5 to 6 hours of direct sunlight each day during the growing season 
  • Partial shade: 2 to 4 hours of sun a day 
  • Shade: only filtered light for the entire day 

Sun-loving plants may survive in shade but won’t prosper or bloom well. Shade-loving plants in sun will probably sunburn and may die.  For a more detailed glossary of sun, shade and other gardening terms, see Great Plant Picks.  The Great Plant Picks site is also an excellent for source for plant recommendations that do well in the Pacific Northwest.  

Think Log Term

Choosing plants that become too large for their location is a common gardening mistake. Don’t think about the size of the plant now; consider its full-grown size. The plant tag should tell you the expected height and width of the mature plant. (note: H and W are estimated for the plant at approximately 10 years of age, so long growing species may get significantly larger…plan accordingly). The Sunset Western Garden Book (2012) is a good reference for plant descriptions, including size and cultural requirements. 

Select “Short Season” Vegetable Varieties 

Even though we have a long growing season, the weather is relatively cool, so you may not be able to grow some of the vegetables that thrive in hotter parts of the country. For example, tomatoes can be successfully grown here, but short-season varieties should be selected. Seed listings in the West Coast Seed Catalogue or  Territorial Seed Catalogue, can help you identify vegetable (and flower) varieties  that can usually be reliably grown here. Many of those seeds and plants (and more) will be available at local nurseries. 

Proper Planting 

Most landscape planting is best done in spring or fall. Dig a hole no deeper than the root mass and at least twice as wide. Remove any burlap and tying materials and loosen the roots. You want the roots to spread into native soil, so don’t add any fertilizers, organic matter or other amendments. Place the plant so that the base of the stem or trunk is slightly above the soil surface. Unless the site is windy, don’t stake plants. If you do use stakes, be sure to remove them after one growing season. For more planting advice, see WSU publication FS047E, “Planting Trees and Shrubs in the Landscape,” available at pubs.extension.wsu.edu

Watering and Mulching 

Despite its rainy reputation, the Puget Sound area typically gets only 3 inches of rain for the entire summer. Some plants in your garden need an inch of water a week or more during this time. 

The objective of good irrigation is to apply water carefully and slowly so that it wets the entire root zone. Quick, light sprinkling will not do the job. Frequent, shallow watering leads to shallow roots, and shallow roots lead to more rapid stress under dry or hot conditions. Water less frequently: once or twice a week but deeper. Take a trowel and dig down several inches and see whether water has penetrated to that level. Try to avoid watering from above the plant: Getting water on the leaves can encourage fungal diseases.  

Consider adding mulch to your landscape. Mulch will help retain moisture, control weeds and contribute to healthy soil. WSU recommends arborist wood chips. See WSU publication FS160E, “Using Arborist Wood Chips as Landscape Mulch, available at pubs.extension.wsu.edu, for more information. 

Mowing 

Many people set their mowers too low and cut the grass too short. Set your mower so that it cuts the grass no shorter than 2 to 3 inches. Don’t remove more than one-third of the grass leaf at any one cutting. That will encourage deeper, healthier roots, help retain moisture, and help the grass compete with weeds.  

Leave clippings on the lawn; they will quickly decompose and add nutrients back into the soil. Consider using a mulching mower to chop up grass clippings before depositing them on the lawn. Contrary to common belief, grass clippings do not cause a buildup of thatch. Avoid weed & feed fertilizers.