Puget Sound Region
Plant guides, pest timing, and seasonal intelligence for the Puget Sound region.
In-depth profiles, disease diagnostics, spray windows, and care schedules calibrated to this climate, this soil, and this growing season.
Featured Guide
Nurse Stumps and Nurse Logs: How Dead Wood Grows New Forests
Nurse stumps and nurse logs are the primary way old-growth forests regenerate in the Pacific Northwest. Learn how decomposing wood grows new trees, what stilt roots and colonnades reveal about forest history, and how to bring the same ecology into your garden.
Latest Guides
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How a Leaf Works: Stomata, Transpiration, and Why Leaves Fall
The internal architecture of a broad leaf: epidermis and cuticle, palisade and spongy mesophyll, chloroplasts, stomata and guard cells, transpiration, antitranspirants, and the controlled shutdown of abscission.
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Leaf Spot Diseases: When to Worry and What to Do About It
Most leaf spots on established plants are cosmetic. Learn to tell the difference between harmless spotting and the few leaf spot diseases that actually threaten plant health in the Puget Sound lowlands.
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How Conifer Needles Work: Why Evergreens Are Built Differently
The internal architecture of conifer needles and awl leaves: thick cuticle, sunken stomata, compact mesophyll, and the water-conservation engineering that lets conifers photosynthesize through a Puget Sound winter.
Read more →Recently Researched
Profile updates driven by guide research and source monitoring
Spotted Lanternfly, Upper and Lower Stem Canker (Phoma Blight), Cypress tip moth, and 5 more profiles updated with damage descriptions, overwintering location, host range, and 14 more areas from OSU Extension - How to manage apple scab during..., OSU Extension - SLF forecast model impact page, OSU Extension - Vaughn Walton, OSU Extension..., and 4 other sources.
OSU Extension - How to manage apple scab during..., OSU Extension - SLF forecast model impact page, OSU Extension - Vaughn Walton, OSU Extension..., and 4 other sources
6 disease profiles enriched with regional notes and chemical control options from Alabama Extension, Morton Arboretum, NC State Extension, and 6 other sources.
Alabama Extension, Morton Arboretum, NC State Extension, and 6 other sources
Read the guide →Slug enriched with identification details, host range, lifecycle stages, and 5 more areas from Cornell Biocontrol, Cornell IPM, Edwards et al. 2009, and 14 other sources.
Cornell Biocontrol, Cornell IPM, Edwards et al. 2009, and 14 other sources
Garlic Mustard enriched with regional notes.
Powdery Mildew enriched with causal agent identification, causal agent by host, host range, and 2 more areas from Cornell PDDC, PNW Plant Disease Management Handbook, UC Davis IPM, and 3 other sources.
Cornell PDDC, PNW Plant Disease Management Handbook, UC Davis IPM, and 3 other sources
Scab profile updated with new regional notes from OSU Extension: 'How to manage apple scab during...
OSU Extension: 'How to manage apple scab during...
Iron Chlorosis enriched with trigger threshold (pH >7 VERIFY flag) and regional notes from NC State Extension Gardener Handbook Ch 1, UC IPM, and UC IPM pH Problems.
NC State Extension Gardener Handbook Ch 1, UC IPM, and UC IPM pH Problems
Read the guide →Ground Beetles (Carabidae) enriched with target pest species, pest profile links, native status, and 4 more areas from Ahn et al. 2012 (ZooKeys 147:497-543), Ahn et al. 2012 on Nebria brevicollis establishment, OSU EM 9301 (Reich et al. 2021), and 5 other sources.
Ahn et al. 2012 (ZooKeys 147:497-543), Ahn et al. 2012 on Nebria brevicollis establishment, OSU EM 9301 (Reich et al. 2021), and 5 other sources
Read the guide →10 plant profiles enriched with regional notes, cultivar data, soil drainage preferences, and 9 more areas from Briggs Nursery, USPP database, OSU Landscape Plants, Pacific Horticulture, Pacific Horticulture community planting framework, and 13 other sources.
Briggs Nursery, USPP database, OSU Landscape Plants, Pacific Horticulture, Pacific Horticulture community planting framework, and 13 other sources
Read the guide →Common Fig enriched with cultivar data, regional notes, cultural practices, and disease susceptibility from Cloud Mountain Farm Center, Gardener's Path, Gardener's Path, Gardener's Path, Cloud Mountain Farm Center, and 7 other sources.
Cloud Mountain Farm Center, Gardener's Path, Gardener's Path, Gardener's Path, Cloud Mountain Farm Center, and 7 other sources
Fig Mosaic Disease enriched with infection conditions, cultural management practices, and vulnerability timing from PNW Plant Disease Management Handbook, Wikipedia,... and Wikipedia (Fig mosaic virus) - vectored by Aceria...
PNW Plant Disease Management Handbook, Wikipedia,... and Wikipedia (Fig mosaic virus) - vectored by Aceria...
Mason Bees (Osmia lignaria) enriched with regional notes and related beneficial organisms from OSU Extension Pollination Podcast Episode 214 and WSU HortSense.
OSU Extension Pollination Podcast Episode 214 and WSU HortSense
Read the guide →The Field Brief
Seasonal scouting notes, spray timing updates, and the regional detail that national guides leave out. Written for Western Washington gardeners and landscape professionals.
Get the Field Brief
Seasonal scouting notes, timing updates, and the regional detail that national guides leave out. Delivered when it matters.
Plant Profiles
Species selection, siting, and care for this climate.
Blueberries: Why the Easiest Fruit Here Is the One People Get Wrong
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Hydrangea Selection for the Puget Sound Lowlands
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Native Groundcovers: What Your Soil Decides for You
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Tomato Varieties That Actually Ripen Here
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Crabapple Varieties That Earn Their Space
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Apple Varieties That Actually Work Here
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Callery Pear (Pyrus calleryana)
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Pacific Wax Myrtle (Morella californica)
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Black Cottonwood (Populus trichocarpa)
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Oregon White Oak (Quercus garryana)
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Pacific Dogwood (Cornus nuttallii)
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Pacific Madrone (Arbutus menziesii)
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Western Hemlock (Tsuga heterophylla)
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Western Redcedar (Thuja plicata)
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Western Serviceberry (Amelanchier alnifolia)
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Catawba Rhododendron (Rhododendron catawbiense)
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Cherry Laurel (Prunus laurocerasus)
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Ponderosa Pine (Pinus ponderosa)
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Strawberry Tree (Arbutus unedo)
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Gulf Stream Nandina (Nandina domestica 'Gulf Stream')
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Vine Maple (Acer circinatum)
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Rose of Sharon (Hibiscus syriacus)
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Red-Flowering Currant 'King Edward VII' (Ribes sanguineum)
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Karl Foerster F (Calamagrostis x acutiflora 'Karl Foerster')
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Red Alder (Alnus rubra)
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Creeping Oregon Grape (Mahonia repens)
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Red Obelisk Beech (Fagus sylvatica 'Red Obelisk')
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Sky Pencil Holly (Ilex crenata 'Sky Pencil')
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Kinnikinnick (Arctostaphylos uva-ursi)
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Cripps Golden Hinoki Cypre (Chamaecyparis obtusa 'Crippsii')
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Sitka Spruce (Picea sitchensis)
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Silk Tree (Albizia julibrissin)
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Bigleaf Maple (Acer macrophyllum)
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Bitter Cherry (Prunus emarginata)
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Paperbark Maple (Acer griseum)
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Judas Tree (Cercis siliquastrum)
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Pagoda Dogwood (Cornus alternifolia)
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Flowering Dogwood (Cornus florida)
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Japanese Maple (Acer palmatum)
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Japanese Maple (Acer palmatum)
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Douglas-fir (Pseudotsuga menziesii)
Read more →Disease Guides
Identification, timing, and management grounded in regional extension data.
Leaf Spot Diseases: When to Worry and What to Do About It
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Fire Blight Bloom Window: Reading the Risk and Knowing When to Act
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Gray Mold: The Disease Your Climate Was Designed For
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Apple Scab: The Disease You Can Plan Against
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Anthracnose: Two Diseases, One Name
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Armillaria Root Rot: Prevention in a Fungus-Loaded Landscape
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Fire Blight vs. Pseudomonas: Diagnosing Spring Shoot Blight
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Verticillium Wilt: The Soil Disease That Outlasts Everything
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Black Spot on Kelsey's Dogwood: Diagnose, Treat, Prevent
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Powdery Mildew: Why Your Climate Gives You an Advantage
Read more →Pest Guides
Scouting, thresholds, and IPM for the pests that actually matter here.
Aphids: Why Spraying Is Usually the Wrong First Move
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Eriophyid Mites: The Invisible Pest Behind Galls, Blisters,
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Leafminers: The Pest You Can Almost Always Ignore
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Root Weevil: The Night Shift Pest in Every Western
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Spider Mites: The Pest That Thrives When Your Plants Are
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Crane Flies: What They Do to Your Lawn
Read more →The Reference Library
A growing dataset of plants, diseases, and pests tracked for this region. Profiles deepen continuously as site data, phenology, GDD timing, and cultivar performance are verified from extension research and field observation.
Written by Chris Welch. Every recommendation on this site comes from someone who works with these plants in this climate, not a content team repackaging national data.
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