Side-by-Side Comparison
Lawn & Garden
Fertilizer N-P-K vs. Plant Hardiness Zones
Comparing 2 standards across 17 specifications. 17 key differences identified.
Comparing:
Fertilizer N-P-K
Plant Hardiness Zones
Fertilizer labels display three numbers representing percentage by weight of Nitrogen (N) for foliage growth, available Phosphate (P2O5) for root development, and soluble Potash (K2O) for drought and cold hardiness.
The USDA Plant Hardiness Zone Map divides North America into 13 geographic zones based on the average annual extreme minimum winter temperature in 10°F (-5.6°C) increments, subdivided into 5°F 'a' and 'b' half-zones to determine plant winter survival.
Specification Comparison Table
17 Parameters| Parameter / Spec | ||
|---|---|---|
|
Governing Standards
|
AAPFCO Guaranteed Analysis / USDA Fertilizer Sizing Guidelines | USDA Plant Hardiness Zone Standard (1990–2023 30-Year Normals) |
|
First Number (N)
|
Nitrogen % | Promotes rapid leaf blade growth and green chlorophyll synthesis | — |
|
Second Number (P)
|
Phosphate (P2O5) % | Stimulates root establishment and blossom/fruit set | — |
|
Third Number (K)
|
Potash (K2O) % | Strengthens cell walls for drought, heat, and disease resistance | — |
|
Balanced All-Purpose (10-10-10)
|
10% N, 10% P2O5, 10% K2O (General vegetable garden & flower bed standard) | — |
|
Lawn Maintenance (24-0-11)
|
High nitrogen turf blend for established lawns without phosphorus runoff | — |
|
Starter Fertilizer (18-24-12)
|
High phosphorus blend for new sod establishment and seed germination | — |
|
1.0 lb Nitrogen per 1k sq ft Rule
|
Lbs of product = 100 ÷ Nitrogen % (e.g. 20-5-10 requires 5.0 lbs/1,000 sq ft) | — |
|
Zone Temperature Increment
|
— | 10°F (5.6°C) per main zone number | 5°F (2.8°C) per 'a' and 'b' half-zone |
|
Zone 3 (Extreme North)
|
— | -40°F to -30°F (-40.0°C to -34.4°C) | Birch, Spruce, Haskap berry |
|
Zone 4 (Northern Cold)
|
— | -30°F to -20°F (-34.4°C to -28.9°C) | Sugar Maple, Honeycrisp Apple |
|
Zone 5 (Upper Midwest / NE)
|
— | -20°F to -10°F (-28.9°C to -23.3°C) | Oak, Dogwood, Lavender |
|
Zone 6 (Mid-Atlantic / Midwest)
|
— | -10°F to 0°F (-23.3°C to -17.8°C) | Boxwood, Peach, Hydrangea |
|
Zone 7 (Transitional / South)
|
— | 0°F to 10°F (-17.8°C to -12.2°C) | Crape Myrtle, Fig, Magnolia |
|
Zone 8 (Deep South / PNW)
|
— | 10°F to 20°F (-12.2°C to -6.7°C) | Rosemary, Camellia, Oleander |
|
Zone 9 (Subtropical South)
|
— | 20°F to 30°F (-6.7°C to -1.1°C) | Citrus, Avocado, Hibiscus |
|
Zone 10 (Tropical / Frost-Free)
|
— | 30°F to 40°F (-1.1°C to +4.4°C) | Bougainvillea, Mango, Banana |