SOIL AND PLANT ANALYSIS (1+1)

When to sample?

• Fields used for crop production are best sampled at any time after harvest and before planting.
• Collect samples after harvest, usually three to six months before planting or three months of after fertilizer application.
• Doing so gives time to plan a liming and fertilization programme before the busy planting season.
• Sample whenever subnormal growth or plant discoloration occurs.
• For coastal soils, collect samples every two years or test one half of the land every year.
• Sandy soils lose nutrients quickly and become acidic when nitrogen is added.
• For mountain or variegated soils, collect samples every three years or test one third of land every year.
• Silt and clay loam soils do not lose nutrients as quickly as sandy soils. Do not sample immediately after fertilizer has been applied.
• Soils should be tested as often as necessary to determine the influence of cultural practices and crop production on soil chemical properties. Nitrogen results are usually the most variable.
• So take samples as close to planting time as possible. Nitrate –N concentrations should be determined on annual basis.
• Phosphorus and potassium should be tested every three to four years. To account for seasonal variations, soil samples should be collected at approximately same time each year.

Do Not Sample


• Dead or back furrows
• Fencerows, old or new
• Old roadbeds, or near limestone gravel roads
• Terrace channels
• Wind breaks or snow fence lines
• Turn-rows
• Spill areas