In-depth plant profiles, disease identification, and pest management for Western Washington.
English laurel shothole has four distinct causes, and only one responds to fungicide. Learn to diagnose fungal, bacterial, physiological, and copper-induced shothole, and when to leave it alone.
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The two weeks after bloom are the most important weeks of the rhododendron year. How to read three diagnostic signals and act before the window closes.
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Ground beetles (family Carabidae) are the largest predator group working your soil surface in the Puget Sound lowlands. They eat slugs and slug eggs, cutworms, crane fly larvae, and root maggots, and they do it year-round.
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Most people think supporting pollinators means keeping honeybees.It is an understandable assumption: honeybees are the pollinators with the public relations department.
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Wood chips don't deplete soil nitrogen. Learn how to use them effectively as mulch without harming tree health or plant growth.
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Asian pears are easier to grow than European pears here, but the disease that actually kills them in maritime springs is not the one the cultivar tags warn you about. A regional cultivar selection guide built on the Hartman pollination chart and the PNW Handbook.
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Your soil is closer to right than you think, but the cultivar you choose and whether you address drainage before planting determines whether blueberries thrive or decline. A selection guide built on PNW 656 cultivar data crossed with soil tolerance and disease resistance for the Puget Sound lowlands.
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Your hydrangea will not bloom, or it scorched in the heat, or you cannot tell the nursery benches apart. Here is how to match hydrangea species and cultivar to the site you actually have in the Puget Sound lowlands.
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Native groundcovers provide ecological function, reduce maintenance needs, and create resilient landscape solutions for Western Washington gardens.
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The pest most gardeners here call rhododendron lace bug is actually the azalea lace bug. How to tell the three species apart and time your response.
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Balsam woolly adelgid has been in the Pacific Northwest since 1930, quietly removing grand fir from lowland landscapes. Most gardeners have never heard of it. If you have a true fir, you should know what it is and what to look for.
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Three problems kill spring vegetable seedlings in the Puget Sound lowlands: damping off, cutworms, and slugs. Each leaves a different signature and demands a different fix. Learn to read the stem, the soil, and the damage pattern before you reach for a product.
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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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Tree flowers explained from the four whorls outward: perfect vs. imperfect, monoecious vs. dioecious, gymnosperm cones, wind vs. insect pollination, and what flower anatomy means for cultivar selection, fruit set, allergies, and disease management.
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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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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.
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The underground fungal economy that determines how trees thrive: how mycorrhizal partnerships work, what common landscape practices destroy them, and why the most effective management strategy is a list of things to stop doing.
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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.
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How to prune young trees for storm resistance, structural integrity, and decades of trouble-free growth in the Puget Sound region.
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Walk through any Western Washington neighborhood in early spring, and you'll spot the evidence: trees that look like they've been given blunt haircuts,
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Two years ago, your contractor promised you the big Douglas-fir would be fine.The tree had shaded your house for forty years, and the remodel was necessary.
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Frost cracks are radial bark separations in tree trunks caused by rapid temperature fluctuations. Learn how to prevent them and what to do if they occur.
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You walk into your local nursery in the Puget Sound region and find a 15-gallon Douglas-fir or Japanese maple.
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Selecting the right tree starts with understanding your site conditions: light, water, soil, exposure, and space. Match these to the tree's requirements.
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The six weeks after bloom are when next year's flowers are made. Here is why spring bulb foliage matters, what kills re-bloom, and how to design plantings so the ugly phase never bothers you.
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If you have been pruning your fig tree the way the internet tells you to and wondering why you get leaves but almost no fruit, the problem is not your tree.
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Soil temperature controls seed germination and transplant survival in spring. Know the minimum soil temperatures for your vegetables.
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National spring lawn advice assumes winter dormancy. Puget Sound lawns skip that step. Here is what to do about moss, compaction, and clay soil damage instead.
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Growing degree days are the accumulated heat units that drive every biological event in your landscape. HortGuide uses base 32°F for maritime climates.
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You are reading a pest profile, a nursery tag, or a soil report and you hit it: *Otiorhynchus* sp.Or maybe *Otiorhynchus* spp. One *p* or two.
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I watched a grower in this region lose thousands of lavender starts in a single freeze because of a name.
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Growing degree days (GDD) measure heat accumulation and predict pest emergence, disease development, and plant phenology. Learn to interpret GDD data for your region.
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Your Puget Sound soil is already acidic, and most of the time that is exactly right. Learn when pH actually needs changing, which amendments work on which soil types, and how to stop chasing a number.
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You dig a hole for a new shrub in April and the bottom fills with water.You wait two weeks, try again, and get the same result.
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Soil compaction reduces root growth, drainage, and water availability. Learn how to identify compacted soils and improve them for tree health.
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