Nursery Pots vs. Plant Hardiness Zones
Comparing 2 standards across 17 specifications. 17 key differences identified.
Plant nursery containers are standardized by ANSI Z60.1 into 'Trade Gallons', where a nominal #1 Trade Gallon holds approximately 0.70–0.80 liquid gallons (2.6–3.0 L) and measures 6.0–6.5 inches in diameter, rather than a full US liquid gallon.
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
|
ANSI Z60.1 (Nursery Stock Specifications) | USDA Plant Hardiness Zone Standard (1990–2023 30-Year Normals) |
|
#1 Trade Gallon (1 Gal)
|
Top: 6.0–6.5" (15–17 cm) | Depth: 6.5–7.0" (17–18 cm) | True Vol: 0.70–0.80 liquid gal (2.6–3.0 L) | — |
|
#2 Trade Gallon (2 Gal)
|
Top: 8.5–8.75" (22 cm) | Depth: 8.5" (22 cm) | True Vol: 1.5–1.6 liquid gal (5.7–6.0 L) | — |
|
#3 Trade Gallon (3 Gal)
|
Top: 10.5–11.0" (27 cm) | Depth: 9.5–10.0" (24–25 cm) | True Vol: 2.6–2.9 liquid gal (9.8–11.0 L) | — |
|
#5 Trade Gallon (5 Gal)
|
Top: 10.75–12.0" (27–30 cm) | Depth: 10.5–11.5" (27–29 cm) | True Vol: 3.6–3.9 liquid gal (13.6–14.8 L) | — |
|
#7 Trade Gallon (7 Gal)
|
Top: 14.0" (35.6 cm) | Depth: 11.5" (29.2 cm) | True Vol: 6.0–6.5 liquid gal (22.7–24.6 L) | — |
|
#15 Trade Gallon (15 Gal)
|
Top: 17.5–18.0" (44–46 cm) | Depth: 15.0" (38 cm) | True Vol: 13.0–13.5 liquid gal (49.2–51.1 L) | — |
|
Standard 1020 Flat
|
11.0 × 21.25 × 2.4 inches (28 × 54 × 6 cm) | Standard 72-cell plug seedling flat | — |
|
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 |