Back to Earth Organics Rock Phosphate
Best natural phosphorus source for gardeners seeking stronger roots and yields.
This natural amendment provides essential phosphorus to support key plant functions, promoting robust photosynthesis, growth, and high yields. It acts as a slow-release feed, delivering nutrients as plants need them to encourage strong root development, abundant flowering, and successful fruit production. Recommended for both spring and fall applications, it can be applied at a doubled rate in the fall for enhanced winter hardiness. This formulation is suitable for a wide range of growing zones, supporting lawns and vegetable gardens effectively.
$14.99
Owner Satisfaction
4.5
/ 5
Category Rank
3104
/ 4456
#3104 in Fertilizers
Price vs Category Average
-76%
Below average
Package Weight
5
/ Pounds
Who it's for
- Farmers aiming for stronger plant cell wall development
- Gardeners seeking consistent, season-long plant nutrition
- Organic growers prioritizing natural soil fertility inputs
Who should skip it
- Users sensitive to airborne dust during application
- Gardeners needing an immediate nutrient boost for plants
- Growers managing neutral or alkaline soil environments
Performance breakdown
Nutrient Release Stability
Slow-release formula prevents nutrient burn and ensures consistent plant uptake.
Root Development Support
High phosphorus content provides the essential foundation for robust root systems.
Application Versatility
Effective across all growing zones for both spring and fall feeding.
Yield Enhancement
Optimized for maximizing flower production and fruit set in home gardens.
Ease of Application
Simple broadcast method makes soil amendment straightforward for any skill level.
Organic Integrity
All-natural sourcing aligns perfectly with sustainable and chemical-free gardening practices.
Key Specs
Package Weight
5 Pounds
Application Rate
2 lbs per 100 sq ft
Growing Zones
1-11
Organic Status
All natural source
Former Brand Name
Soil Mender
Release Type
Slow Release
Season of Use
Spring, Fall
Primary Benefit
Root Growth
Know before you buy
Back to Earth Organics Rock Phosphate is an all-natural, slow-release source of phosphorus. Unlike synthetic options that provide an immediate, high-concentration burst, this product breaks down gradually to feed your plants only as they require it, which helps prevent over-fertilization.
Yes, this fertilizer is suitable for use in growing zones 1 through 11. Its versatility makes it an effective choice for gardeners across a wide range of climates and environmental conditions.
The standard application rate is 2 pounds per 100 square feet. You can apply it in both the spring and fall, and you may choose to double the rate during your fall application to help improve your plants' winter hardiness.
Absolutely. Phosphorus is essential for energy transfer within plants, and this formula is specifically designed to support robust flowering and higher yields for fruit and seed-bearing crops.
Yes, Back to Earth Organics Rock Phosphate is the same formulation formerly sold under the brand name Soil Mender. You can expect the same performance and natural composition you are familiar with.
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