Winterizer
A fall fertilizer high in potassium and lower in nitrogen applied before the lawn goes dormant. Winterizer helps grass store energy, harden cell walls against cold, and green up faster in spring. It is one of the most beneficial treatments a lawn owner can do.
Winterizer fertilizers typically have ratios like 24-0-12 or 13-0-26 — emphasizing potassium (K) for cold hardiness over nitrogen (N) for growth. Applied in October–November before the ground freezes, winterizer helps the grass store carbohydrates and minerals it will use when growth resumes in spring.
Timing: Apply when the lawn has slowed growing but is still green. For cool-season grasses, this is usually mid-to-late October through mid-November. For warm-season grasses, early-to-mid September before dormancy.
Result: Faster spring green-up, stronger root system, improved disease resistance over winter.
More on Fertilizer
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