s_zm_golf_1_450x300Soil Texture

Porosity and Texture

EcoSand Benefits Include:

  • Improved Drainage (infiltration rate)
  • Increased Water holding (field capacity)
  • Reduced Density
EcoSand Natural Zeolite Soil Amendment improves both porosity and texture. With over 500 times the surface area of quartz sand, EcoSand improves the water holding capacity of the soil without reducing the drainage. Since EcoSand has a lower density than sand, adding EcoSand will reduce the density of the soil and make the soil sandier and lighter.

University testing showed that mixing 15% EcoSand with sand that meets USGA specifications gave the following results:

Profile of 15% EcoSand Mixed with Sand

Drainage (cm/hr)
Water Holding (%)
Bulk Density (g/cm3)
EcoSand Zeolite
© ZEO, Inc. EcoSand Green Soil Amendment

The improved water flow or infiltration rate is due to EcoSand having a slightly larger particle size than sand. Typically, increasing the flow through the root zone leads to reducing the water holding capacity. However, the rough or porous surface of EcoSand holds more water in the soil. The soil bulk density is lower because EcoSand has a bulk density of 55 pounds per cubic foot (0.88 g/cm3) versus sand at 97 pounds per cubic foot (1.56 g/cm3). Lowering the bulk density reduces the tendency of the soil to compact.

EcoSand is low clay (>1%) clinoptilolite form of natural zeolite—mined, air dried, crushed and screened to be slightly larger than USGA sand:

ZEO EcoSand Natural Zeolite Comparison to Sand

Compared to Sand
Greater than 14 Mesh
>1.18 mm (>0.046 inches)
 14 x 40 Mesh
0.425 to 1.18 mm
Average Particle Size
0.88 mm
Size Guide Number (SGN)
88 (d50)
Uniformity Index (UI)
1.8 (d95/d10)
© ZEO, Inc. EcoSand Green Soil Amendment

Soil texture is due to composite of three particle sizes:

ZEO EcoSand Composite Particles

0.02 to 2 mm
0.02 to 0.002 mm
 < 0.002 mm
© ZEO, Inc. EcoSand Green Soil Amendment


Since there is more open space between sand particles, pore space increases as the soil becomes sandier. The finer particle size silt and clay particles fill up the open space between the sand particles. Smooth sand with a small surface area can add large pore space to hold air but does not increase the water holding capacity of the soil. Silt and clay fill the spaces between the sand particles and increase the water holding capacity while reducing the drainage rate.

Due to its smooth surface, quartz sand has a small surface area of about 0.05 square meters per gram or 224 square feet per pound. As a result of this small surface area, water is not held in the root zone and easily drains through quartz sand based soils. For comparison, grinding a feldspar sand to less than 325 mesh, a particle similar to baby powder increases the surface area to 1.1 square meters per gram or 5,000 square feet per pound.

In contrast to sand, EcoSand has an extensive surface area of 29.3 square meters per gram (143,000 square feet per pound) – that is an amazing 3.2 acres per pound or 2.9 hectares per kilogram. The unique three dimensional honeycomb structure gives EcoSand the small pores for the vast surface area where water can be retained for the plant to use.