Side-by-Side Comparison
Lawn & Garden
Mulch & Soil Coverage vs. Plant Hardiness Zones
Comparing 2 standards across 18 specifications. 18 key differences identified.
Comparing:
Mulch & Soil Coverage
Plant Hardiness Zones
Bulk mulch, topsoil, and gravel are measured in Cubic Yards (27 cubic feet / 0.764 m³). One cubic yard covers 324 sq ft at 1 inch depth, 162 sq ft at 2 inches (standard flowerbeds), or 108 sq ft at 3 inches (weed suppression), equivalent to 13.5 bags of 2 cu ft mulch.
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
18 Parameters| Parameter / Spec | ||
|---|---|---|
|
Governing Standards
|
NIST Handbook 130 (Method of Sale for Mulch and Bulk Soils) | USDA Plant Hardiness Zone Standard (1990–2023 30-Year Normals) |
|
Cubic Yard Formula
|
(Length in Feet × Width in Feet × Depth in Inches) ÷ 324 = Cubic Yards | — |
|
1 Cubic Yard Volume
|
27 cubic feet (0.764 cubic meters / 202 liquid gallons) | — |
|
Coverage at 1" Depth
|
324 square feet (30.1 square meters) | — |
|
Coverage at 2" Depth
|
162 square feet (15.1 square meters) | Standard flowerbed top-dressing | — |
|
Coverage at 3" Depth
|
108 square feet (10.0 square meters) | Standard weed barrier & tree rings | — |
|
Coverage at 4" Depth
|
81 square feet (7.5 square meters) | Playground mulch / raw grade build-up | — |
|
2.0 Cu Ft Bag Equivalent
|
13.5 bags = 1 Cubic Yard (Standard retail bag size) | — |
|
3.0 Cu Ft Bag Equivalent
|
9.0 bags = 1 Cubic Yard | — |
|
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 |