The unique landscape provided by the green beauty coupled with the distinctive climate in Seattle makes a very special canvas for ornamental trees.
Such living sculptures transform outdoor areas as they not only make the area look pretty, but also give people a closer relationship with the environment.
The purpose of this guide is to provide the Seattle homeowners, landscapers and gardening enthusiasts with all the knowledge and helpful hints that they need in order to make confident decisions when choosing, planting and maintaining ornamental trees that will not just grow and blossom in Pacific Northwest but also benefit their properties in terms of appreciation of value and the overall beauty of the landscape.
What are Ornamental Trees & Why Choose Ornamental Trees for Seattle Landscapes?
Ornamentals trees are planted mainly because of their beauty as they are appreciated for their aesthetic appearance, unique general form, lush foliage as well as their fascinating flowers. They are not a means of livelihood similar to timber trees or food-growing trees. They tend to be smaller than their wild counterparts. Many are deciduous and are usually maintained on a regular basis, either every year or couple of years.
Benefits of Ornamental Trees in Seattle Landscapes
There are numerous advantages of investing on ornamental trees:
- Property Value Increase: Research shows that mature aesthetic trees have the capability of increasing the value of a property by 10% on average and as much as 20%. This turns ornamental trees into a smart investment that helps in improving the marketability of a given house or property.
- Seasonal Interest: These are trees giving the year round visual appeal. They provide colorful spring flowers, full summer growth, dazzling colour in fall and architectural interest in the winter, ensuring a constantly evolving and fascinating landscape.
- Climate Adaptability & Energy Savings: Strategically placed trees have a capacity to generate natural cooling and heating effects on houses. Mature trees around the buildings have the capability of cutting the air conditioning by 30% and also reduces the cost of heating by 20-50%. This is especially useful in Seattle, since careful planting can soften heat during the summer, and lower energy use.
Best Ornamental Trees for Seattle Climate
Proper choice of the ornamental tree to use in the Seattle landscape needs an advanced approach to the climate of the area other than hardiness zones.
01. Japanese Maple Trees: Seattle’s Favorite Ornamental
Japanese Maples (Acer palmatum) are highly prized for their delicate foliage, graceful forms, and vibrant seasonal colors, making them a perennial favorite in Seattle landscapes.
Varieties that Thrive in Seattle
Varieties well-suited for Seattle’s climate include ‘Bloodgood’, ‘Emperor I’, and ‘Coral Bark’ (Acer palmatum ‘Sango Kaku’). ‘Coral Bark’ is particularly celebrated for its striking vivid red-orange stems in winter, which provide exceptional visual interest against a stark winter backdrop, and it has been recognized as a Pacific Northwest “Great Plant Pick”.
It is important to note that ‘Coral Bark’ can be “somewhat ‘fragile’ and often doesn’t have a long lifespan”. Careful microclimate matching and consistent care are paramount to ensuring the longevity and health of these beloved trees.
Size Considerations for Seattle Lots
Japanese Maples encompass a wide range of sizes, from true dwarf cultivars perfect for containers or very small urban gardens to larger specimens that can reach 15-25 feet tall and 15-20 feet wide at maturity.
Given Seattle’s increasingly denser urban environment and new zoning regulations that often lead to smaller residential lots and reduced green space , selecting a Japanese Maple with a mature size appropriate for the available planting area is crucial for long-term success and to avoid overcrowding.
02. Cherry Trees: Spring Flowering Spectacles
Seattle’s spring landscape is famously adorned by ornamental cherry trees, which herald the arrival of warmer weather with their breathtaking blooms.
Ornamental Varieties
Key varieties that thrive in the region include ‘Kwanzan’ (Prunus serrulata ‘Kwanzan’), ‘Yoshino’ (Prunus x yedoensis), and ‘Akebono’ (Prunus x yedoensis ‘Akebono’).
- ‘Kwanzan’ is particularly renowned for its “cotton candy double pink flowers in April” that hang in pendulous clusters.
This variety was specifically bred for ornamental purposes and does not produce edible fruit. ‘Yoshino’ is a widely popular hybrid, known for its abundant white, almond-scented flowers and broad, spreading habit. ‘Akebono’ features delicate pale pink single flowers that gradually fade to white.
For instance, ‘Yoshino’ cherry trees tend to bloom one to two weeks earlier than ‘Kwanzan’ , allowing for a prolonged spectacle.
Connection to Seattle’s Cherry Blossom Festivals
Ornamental cherry trees in Seattle transcend mere botanical interest, they are deeply woven into the city’s cultural fabric.
Seattle embraces its cherry blossom season with various celebrations, highlighting the cultural significance and community appreciation for these trees.
The annual Seattle Cherry Blossom & Japanese Cultural Festival is a significant event, typically held in April (e.g., April 11-13, 2025).
Additionally, the U District Cherry Blossom Festival takes place, often in late March (e.g., March 30, 2024), celebrating the historic cherry blossom viewing on the University of Washington Quad. These festivals underscore how these trees contribute to a sense of place and local traditions.
03. Dogwood Trees: Four-Season Beauty
Dogwood trees are celebrated for their multi-seasonal appeal, offering beauty throughout the year.
Pacific Dogwood vs. Kousa Dogwood Performance in Seattle
The Pacific Dogwood (Cornus nuttallii) is native to the Pacific Northwest and offers elegant white bracts in spring, red berries in fall, and a graceful habit. It is a woodland gem with four-season charm and serves as an excellent pollinator and wildlife tree.
The Kousa Dogwood (Cornus kousa) is an Asian variety that performs exceptionally well in Seattle and is highly valued for its abundant white blooms in early summer (which appear later than native dogwoods), elegant form, and interesting bark. Its fruit is larger and edible, attracting birds.
Disease Resistance Considerations for Seattle Climate
Seattle’s moist climate can promote fungal diseases, making disease resistance a crucial factor in tree selection. Dogwood Anthracnose (caused by Discula destructiva) is a common issue for dogwoods, thriving in wet and cool spring conditions and manifesting as leaf spots, blotches, cankers, and twig dieback.
The Kousa Dogwood is highly regarded for its resistance to anthracnose , making it a more reliable choice for many Seattle landscapes, especially if the site is prone to dampness. This highlights the importance of choosing disease-resistant varieties like the Kousa Dogwood or its hybrids as a proactive and highly effective strategy to minimize long-term maintenance, reduce the need for chemical treatments, and ensure the tree’s longevity.
04. Fruit Trees as Ornamental Features
Fruit trees offer a unique combination of aesthetic appeal and edible bounty, making them excellent dual-purpose ornamental features for Seattle landscapes.
Dual-Purpose Landscaping: Beauty and Harvest
These trees provide beautiful blossoms in spring, lush foliage in summer, and the added benefit of homegrown fruit. Seattle’s abundant rainfall and mild summer weather make it an ideal location for growing many types of fruit trees, including apples and pears.
Best Ornamental Fruit Varieties for Seattle
- Apples: ‘Honeycrisp’ apples are popular. While ‘Honeycrisp’ thrives in colder zones (3-7) and can be sensitive to high humidity and intense summer sun , it is still listed as a good option for Western Washington. Other excellent, often scab-resistant, varieties for Seattle include ‘William’s Pride’, ‘Liberty’, ‘Akane’, ‘Jonagold’, ‘Karmijn de Sonnaville’, and ‘Spartan’.
- Pears: ‘Bartlett’ pears are widely grown. ‘Taylor’s Gold’ is particularly well-adapted to Western Washington’s cool, humid climate, ensuring a uniform russet skin, and is a promising organic candidate. ‘Comice’ is another well-adapted option.
Apple & Pear Espalier and Space-Saving Techniques for Seattle Lots
Espalier is an ancient training method where trees are grown flat against a wall, fence, or trellis. This technique is perfect for maximizing fruit production in small urban gardens, patios, or narrow yards, as it allows for homegrown fruit in limited spaces.
Apple and pear trees are the most commonly espaliered varieties due to their flexible branches and adaptability. Espalier also makes harvesting easier, as fruit remains within arm’s reach.
This method is not just a gardening technique, it is a strategic landscape design solution that directly addresses the challenges of increasing urban density and limited outdoor space in Seattle, allowing homeowners to enjoy the aesthetic and productive benefits of fruit trees without requiring large footprints.
05. Magnolia Trees: Dramatic Spring Displays
Magnolias are renowned for their spectacular, often fragrant, blooms that create a dramatic visual impact in the spring landscape.
Star Magnolia, Saucer Magnolia, and Southern Magnolia Varieties
Varieties commonly grown in Seattle include:
- Star Magnolia (Magnolia stellata): Known for its delicate, star-shaped white or pink flowers that appear very early in spring.
- Saucer Magnolia (Magnolia x soulangeana): Features large, cup-shaped flowers, often pink and white, that create a dramatic display.
- Southern Magnolia (Magnolia grandiflora): An evergreen variety with large, glossy leaves and fragrant, creamy-white flowers. Cultivars like ‘Little Gem’ or ‘Baby Grand’ are smaller, broadleaf evergreen options suitable for smaller city gardens, typically growing to 12-20 feet.
- Magnolias are generally hardy in USDA Zones 4-10, making them well-suited for Seattle’s Zone 9a/9b.
Protection from Late Frost Considerations
While magnolias are generally hardy, their early blooming habit makes them susceptible to damage from late spring frosts.
A sudden drop in temperature after buds have swelled or opened can damage flowers and new growth.
This highlights a trade-off: the very characteristic that makes magnolias so dramatic also makes them vulnerable to unpredictable late spring frosts in Seattle. Homeowners must be aware of this risk and be prepared to provide temporary protection, especially for young or newly established trees.
06. Planting Ornamental Trees in Seattle
Proper planting is the foundation for a healthy, long-lived ornamental tree. In Seattle, specific timing and techniques are crucial.
Best Planting Times: October-March During Dormant Season
Fall is the optimal time to plant new trees in Seattle, specifically between mid-September and early November. Planting during October-December allows trees to benefit from the natural fall and winter rains, promoting strong root system development before the dry summer months. The cool, wet weather and warm soil (50-65°F) in fall provide ideal conditions for root growth and minimize stress on young trees.
Soil Preparation for Seattle’s Clay and Sandy Soils
Seattle soils can present challenges, often being compacted or having high clay content, which leads to poor drainage. Other areas may have sandy soils that drain too quickly. The most effective way to improve any soil is by adding organic matter, specifically compost.
Before planting, mix 2-3 inches (5-8 cm) of compost into the upper 8-12 inches of the entire planting bed. For clay soils, use a slightly lesser amount, about 2 inches of compost; for sandy soils, use 3 inches to improve water retention. It is crucial not to place compost or fertilizers directly into the planting hole, as this can harm roots and cause the tree to settle poorly over time. Instead, amend the entire area and use a thin layer of compost as a top dressing after planting.
Spacing Considerations for Mature Tree Size
Seattle’s new zoning laws may lead to smaller lots and less green space , making careful size selection even more critical to avoid future conflicts.
Utility Clearances: It is essential to plant trees at least 5 feet from underground utility lines, 10 feet from power poles, 20 feet from street lights or other existing trees, and 30 feet from a corner curb.
Overhead Power Lines: Trees planted underneath overhead power lines are not supposed to grow more than around 25 feet once they reach maturity.
Structures: Keep a proper distance between the buildings, driveways and fences so as to avoid any harm of the foundations like the roots digging and affecting the building, or overgrowth of the canopy.
Property lines: Be careful about property lines and how neighbors might be affected, i.e. too much shade, dropping leaves, root invasion etc.
07. Choosing the Right Location for Ornamental Trees
The long-term success and beauty of an ornamental tree are intrinsically linked to its initial placement. Thoughtful site selection is paramount.
Sun/Shade Requirements for Different Species
Different ornamental trees have varying light needs, from full sun to part shade or full shade. Seattle’s climate, with its long stretches of cloud cover, means many plants need to tolerate some shade.
Wind Protection Considerations
Strong winds can significantly damage young trees or species with delicate foliage, such as Japanese Maples. Consider planting trees in locations naturally protected from prevailing winds, or strategically use structures or other plants as windbreaks if the site is exposed.
Proximity to Structures, Utilities, and Property Lines
As previously highlighted in the planting section, proper spacing is crucial to avoid future conflicts and ensure the tree’s health and safety. The unseen network of underground utilities, along with visible structures, dictates precise placement.
08. Seattle Ornamental Tree Care Guide
Consistent and appropriate care is essential for the health and longevity of ornamental trees in Seattle’s unique climate.
Watering Schedules for Seattle’s Dry Summers
Despite Seattle’s reputation for abundant rainfall, summers are notably dry, making consistent watering crucial for tree health. This is a common misconception; while winters are wet, the distinct dry summer period necessitates active, deep watering to prevent heat stress, dehydration, and subsequent vulnerability to pests and diseases.
- Newly planted trees (Year 1): Require 15-20 gallons of water twice a week from May through September.
- Young trees (Years 2-3): During hot, dry periods, deep water stressed trees every 2 weeks.
- Mature trees: Need substantially more water, potentially 1-3 hours of soaking irrigation each month, depending on size. Deep, infrequent watering (every 3-4 weeks) encourages deeper root growth and resilience to drought.
- Avoid shallow watering from lawn sprinklers, as this promotes shallow, less resilient roots. Water early in the morning to reduce evaporation losses.
Mulching Techniques for Moisture Retention
Mulching is one of the most beneficial practices for tree health, serving as a foundational, multi-functional care practice. It helps to retain soil moisture, regulate soil temperature, suppress weed growth, and improve overall soil health and biology.
Apply a 2-4 inch (5-10 cm) thick layer of organic mulch in a “doughnut” shape around the tree. Crucially, keep the mulch 3-6 inches or a hand’s distance away from the tree trunk to prevent rot, pest problems, and the development of stem girdling roots.
Pruning Timing Specific to Seattle Climate
Pruning is essential for maintaining the health, structure, and aesthetic appeal of ornamental trees.
- General Pruning: Winter (from late November/December to mid-February) is an ideal time to prune many deciduous trees in the Pacific Northwest due to their dormant state, which minimizes stress and the risk of disease spread.
- Cherry Trees: Ornamental cherry trees are best pruned in early spring, ideally in March, before sap flow begins. While this may remove some early flowers, it promotes better overall growth.
- Fruit Trees: Pruning is primarily done during the dormant season (November 15-April 15) to maintain an open canopy, allow sunlight penetration, and improve air circulation.
- Regularly remove crossing, rubbing, diseased, or dead branches to improve tree health and appearance. Water sprouts and suckers, which are vigorous upright shoots, should be removed annually.
Common Pest and Disease Issues in Pacific Northwest
Seattle’s moist conditions can favor certain pest and disease issues like Dogwood Anthracnose, Powdery Mildew, Root Rot, Black Spot, Scab and Pests including aphids, bark beetles, and borers.
- Prevention Strategies: Plant Disease-Resistant Varieties, Ensure Good Air Circulation, Proper Watering, Regular Inspection, Sanitation and Balanced Fertilization.
07. Seasonal Care Calendar for Seattle Ornamental Trees
Effective ornamental tree care in Seattle is a holistic, integrated process where each practice influences the success of others.
A seasonal approach ensures proactive health management, aiming to prevent common issues before they become severe.
Monthly Care Tasks Specific to Seattle Climate
Fall (October-November):
- Planting: This is the best time for new tree planting, specifically between mid-September and early November.
- Mulching: Apply a 3-4 inch layer of organic mulch around trees, keeping it away from the trunk.
- Winter Protection: Wrap young tree trunks with white guards to prevent sunscald, applying them in fall and removing in spring. Apply mulch to roots to prevent frost penetration and heaving. If the fall has been dry, water heavily before the ground freezes to ensure adequate moisture for winter.
- Cleanup: Rake up and destroy fallen leaves, especially if they show signs of disease, to remove potential disease spores.
Winter (December-February):
- Pruning: The dormant season is an ideal time for pruning many trees in the Pacific Northwest, as it minimizes stress and disease spread.
- Monitoring: Inspect tree structure and look for signs of disease or pest issues that may become more obvious after leaf drop.
- Watering: Generally, watering is not needed due to abundant rainfall. However, deep water stressed evergreens during any dry spells to help them resist drying from winter sun and wind.
Spring (March-May):
- Pruning: Continue dormant pruning until mid-April. Prune ornamental cherry trees in early spring (March) before sap flow, or immediately after flowering.
- Fertilization: Apply a balanced fertilizer to young trees annually or to established trees showing nutrient deficiency. The best time for application is between early spring and late July/early August, during active growth. Avoid fertilizing newly planted trees immediately.
- Mulching: Refresh the mulch layer around trees.
- Pest/Disease Inspection: Spring is a prime time for spotting early signs of pests and diseases, such as anthracnose, as new growth emerges.
- Watering: Young trees may require watering if spring is unusually dry.
Summer (June-September):
- Watering: Consistent, deep watering is crucial for all trees, especially young ones, during Seattle’s dry summers.
- Mulching: Maintain the mulch layer to retain moisture and regulate soil temperature.
- Monitoring: Continuously monitor for heat stress symptoms such as curling or wilting leaves, scorching, or leaf drop. Also, check for summer pests and diseases.
- Thinning Fruit: For fruit trees, thin fruit if the tree is overburdened to promote larger, healthier fruit and prevent branch breakage.
- Sun Protection: For young or vulnerable trees, temporary shade cloths may be needed during intense heatwaves.
FAQ Section
01. What are the best ornamental trees for Seattle?
The “best” trees depend on specific site conditions (sun, soil, space) and desired aesthetic. However, top performers for Seattle’s climate include Japanese Maples, ornamental Cherry Trees, Dogwoods, Magnolias, and ornamental Fruit Trees.
02. When to prune ornamental trees?
The ideal time for most ornamental trees in Seattle is during their dormant season, typically from late November/December through mid-February. This minimizes stress and disease transmission. However, specific trees like ornamental cherry trees are best pruned in early spring (March) before sap flow or immediately after flowering. Always remove dead, diseased, or crossing branches whenever noticed.
03. How big do ornamental trees get?
The mature size of ornamental trees varies significantly by species and cultivar. They can range from small dwarf varieties that may only reach 10-15 feet, to medium-sized trees up to 20-30 feet, and larger specimens that can exceed 40 feet. Always check the mature height and spread of the specific variety chosen to ensure it fits the available space and avoids conflicts with utilities.
04. What are the ornamental trees that don’t grow tall?
For smaller Seattle lots or planting under power lines, consider ornamental trees that mature at 25 feet or less. Excellent choices include Cascara, Chinese Fringe Tree, Eastern Redbud, and American Smoke Tree. Specific cultivars like ‘Shishigashira’ Japanese Maple, ‘Baby Grand’ Southern Magnolia, and ‘Slender Silhouette’ Liquidambar are also compact options. Dwarf and semi-dwarf fruit tree varieties are also ideal for limited spaces.
05. What is ornamental tree trimming?
Ornamental tree trimming, or pruning, is the practice of selectively removing branches to enhance the tree’s aesthetic appeal, maintain its unique characteristics, and improve its health.
06. When to prune ornamental cherry trees?
Ornamental cherry trees should be pruned in early spring, ideally in March, before the sap starts to flow. While this may remove some spring flowers, it promotes better growth. Pruning can also be done right after the flowering period.
Conclusion
Ornamental trees have an impactful presence in the scenery of Seattle and this influence is not limited to beauty alone; there is a great increase in property value, positive affect on the environment, and an improved quality of life.
These living investments can be very successful as far as the principle of the ”right tree, right place” is followed. It assumes the deep knowledge of unique and changing climate of Seattle and local conditions of soil types, as well as the very complicated urban regulations on the planting and maintenance of trees.
With the recommendations of careful selection and specific planting methods as well as thorough maintenance done throughout the seasons, the homeowners and landscapers alike can cultivate sustainable, beautiful, and healthy landscapes.
For detailed information on Seattle native trees, check out our complete guide.
