Philom Bios Inc.
3935 Thatcher Avenue
Saskatoon, SK Canada S7R 1A3
1-888-744-5662
www.philombios.com
Meeting Phosphate Requirements

Plant-Available Phosphate is Usually Low
Soils can be high in total soil phosphate but low in plant-available phosphate because much of the soil phosphate gets tied up in unavailable forms. As the crop takes up available phosphate, some of the unavailable phosphate is converted to available phosphate. However, this conversion does not take place fast enough to meet the demands of high yielding crops. As a result, crops will likely be deficient in phosphate.

Factors Affecting Phosphate Availability:

  • Soils high in clay content tie up more phosphate than lighter soils.
  • Phosphate is less available at colder soil temperatures.
  • Availability is better in moist soils.
  • Phosphate is more available in soils with a pH of 6.5 to 7.
  • Plants with fibrous roots are better able to take up available phosphate through better soil exploration than plants with a tap root.

Phosphate removal (lb. P2O5 per acre) by crops

Crop Yield per acre Plant Uptake* Removal**
Corn 150 bushel 75 - 110 55 - 66
Soybean 50 bushel 40 - 50 40 - 44
Winter Wheat 75 bushel 50 - 55 40 - 50
Barley 75 bushel 35 - 40 28 - 30
Oats 75 bushel 30 - 35 19
Dry Beans 30 bushel na 25
Pea 50 bushel 38 - 46 31 - 38
Legume Haylage 5 tons/acre na 50 - 80
Grass Haylage 4 tons/acre na 35 - 55
Legume Hay, 1st cut 5 tons/acre na 50 - 80
Grass Hay, 1st cut 4 tons/acre na 35 - 55
Grass Hay, 2nd cut 3 tons/acre na 35 - 50
*Plant uptake is total nutrient taken up by the crop.
**Removal is the amount of nutrient in the harvested portion of the crop.
Source: Canadian Fertilizer Institute.