Latest Plant Selection
Crabapple Varieties That Earn Their Space
Disease-resistant crabapples that stay clean from April bloom through October fruit drop. Organized by size, with pollination data and the native Pacific crabapple.
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In-depth plant profiles, disease identification, and pest management for Western Washington.
Plant Health Care
Mulching: The Cheapest Thing You Can Do for Your Trees
You've probably seen a mulch volcano and helped create one. Here's what that pile is doing to your tree, and how to mulch correctly for the soil under your feet.
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Plant Health Care
Copper Fungicide: The One Spray That Covers the Most Ground
Copper fungicide is one of the few organic materials that works against both fungal and bacterial pathogens. Here is what it controls in the Puget Sound landscape, when to spray it, and the real constraints you need to respect.
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Plant Health Care
Dormant Season Spraying: Your Winter Window for Pest and Disease Control
The most effective pest and disease treatments happen when your trees look dead. Here is what to spray, when to spray it, and why the timing window matters.
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Plant Selection
Apple Varieties That Actually Work Here
Disease resistance, not chill hours, determines which apple trees produce fruit in the Puget Sound lowlands. Nine varieties that need no spray program, plus rootstock and pollination guidance.
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Plant Selection
Callery Pear (Pyrus calleryana)
You already have one. That is the starting point for most conversations about Callery pear (Pyrus calleryana) in Western Washington. It sits in your front yard, lines your street, anchors the...
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Plant Selection
Pacific Wax Myrtle (Morella californica)
A native evergreen that screens, fixes nitrogen, and asks for almost nothing in return. Privacy, wind protection, and soil improvement in one fast-growing package.
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Plant Selection
Black Cottonwood (Populus trichocarpa)
The tallest native hardwood in Western Washington, and why you need to understand it before you decide to keep or remove one.
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Pest & Disease
Apple Scab: The Disease You Can Plan Against
Apple scab is the most reliable fungal disease on any Malus in the Puget Sound lowlands. Identification, the Mills table, cultivar resistance ratings, fall sanitation, and protectant vs. kickback spray timing for Western Washington fruit growers and landscapers.
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Pest & Disease
Bronze Birch Borer: Why Your Birch Is Dying from the Top Down
Bronze birch borer kills stressed birches from the canopy down, and understanding the delay between drought stress and visible damage is the key to saving trees that can still be saved. GDD timing, resistance chemistry, treatment thresholds, and species substitution for the Puget Sound lowlands.
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Pest & Disease
Scale Insects: Identifying and Managing the Two Types That Damage Landscape Plants
Armored and soft scale insects look similar on bark but require completely different management. Learn the field test that separates them, when crawlers emerge by GDD, and why ant exclusion may be the most effective single intervention.
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Pest & Disease
Phytophthora Root Rot: The Water Mold That Loves Your Soil
Why Western Washington's wet winters create perfect conditions for Phytophthora, and how to protect your landscape.
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Arboriculture
Structural Pruning: The First Five Years That Define the Next Fifty
How to prune young trees for storm resistance, structural integrity, and decades of trouble-free growth in Western Washington.
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Arboriculture
Topping: The Harmful Pruning Practice That Persists
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, their canopies reduced to stumpy branches with...
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Site Assessment
Construction Damage to Tree Roots: What You Cannot See Is What Kills the Tree
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. You watched them work around it. No major...
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Site Assessment
Frost Cracks: Why Your Tree Split Open Overnight
You step outside the morning after a cold snap in January and stop cold. A vertical crack runs down the trunk of your maple or cherry, splitting the bark from somewhere high up and descending several...
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Site Assessment
Circling Roots: What Happens When You Plant a Pot-Bound Tree
You walk into your local nursery in the Puget Sound region and find a 15-gallon Douglas-fir or Japanese maple. The tag reads "ready to plant." You load it into your truck, dig a hole in your yard,...
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Site Assessment
Right Tree, Right Place
You can eliminate most tree problems before you plant a single sapling. Match the tree to the site, and you won't spend the next twenty years fighting with dead branches, structural failure, or roots...
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Cultural Practices
Early Spring Lawn Care: What Your Puget Sound Lawn Actually Needs Right Now
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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Cultural Practices
Pruning Grape Vines: A Beginner's Guide to Better Harvests
Your grape variety determines your pruning method. Learn spur pruning vs. cane pruning, wet-climate timing to prevent trunk disease, and a variety-by-variety reference table for the Puget Sound lowlands.
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Cultural Practices
Pruning Clematis: The Three Groups and When to Cut
Clematis confusion starts the moment you bring one home. You've got a beautiful vine covered in flowers, and then someone tells you to prune it. Cut it back hard? Light prune? Wait until next year?...
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Cultural Practices
Watering New Trees: The First Three Years Are Everything
You plant a tree in October. The rain starts in November, and you think you're done. The soil stays wet through winter and spring. By June, you've forgotten about that tree entirely. Then July hits,...
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Concept
Growing Degree Days: The Number That Tells You What Your Plants Are Actually Doing
Growing degree days are the accumulated heat units that drive every biological event in your landscape. HortGuide uses base 32°F for maritime climates. This guide explains the calculation, the conversion methodology, source data, and how to read the season tracker.
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What sp. and spp. Mean (and Why It Matters on a Plant Tag)
One p or two? The abbreviations sp. and spp. after a genus name mean different things. Learn the distinction, the Latin behind it, and how to read them on nursery tags, lab reports, and pesticide labels.
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Concept
Botanical Nomenclature: How to Read a Plant Name
Every nursery tag carries four layers of naming. One of them predicts how the plant will perform in your yard. Learn to decode species, cultivar, trade name, and patent so you buy exactly what you intend.
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Concept
Heat and Growth Metrics: Reading the Season Through Temperature
If you track four numbers through the year, you can predict when your fruit trees will break dormancy, when the soil is warm enough to plant, whether your season is running ahead or behind, and how much solar energy your landscape is actually receiving.
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