Groundnut grows best in deep, well-drained soils with a sandy or very loose surface layer.
|If the moist soil is rubbed between the index finger and the thumb should not form a ribbon but should fall apart easily. Such soil is best for groundnut crop (Fig.).|
In addition to soil fertility, soil - texture is vitally important aspect of groundnut production.
Well - drained, light - textured, loose, friable sandy - loam or sandy clay loam soils (Fig.), well - supplied with calcium and a moderate amount of organic matter are ideal for groundnut cultivation.
- Seed germination and seedling emergence are favored in loose, friable and sandy - loam soils.
- The pegs can penetrate the soil easily and pods can be harvested from such soils with minimum losses of comparatively clean produce. The soil does not adhere excessively to the freshly dug pods in these soils.
- Heavy and fine - textured black (clayey) soils cause serious difficulties in groundnut harvesting with pod loss.
- Also, soil adheres to groundnut pods reducing their marketable quality.
- Where groundnuts must be grown on heavier - textured soils, bunch varieties of groundnut are more suitable.
- The normal yield of groundnut can be obtained on fairly heavy soils with good tilth and favorable moisture conditions.
- Good soil drainage facilitates adequate soil aeration.
- Lack of proper drainage adversely affects root growth, ultimately affecting the plant growth and development.
- In the absence of adequate oxygen in the root zone, beneficial soil bacteria, especially the nitrogen - fixers become ineffective and uptake of nitrogen by roots is hampered.
- Fields with shallow top soil, poorly drained areas and those subject to excessive erosion should be avoided.
- The ill - drained acidic, alkaline and saline soils are not suitable for groundnut production.
- In such problem soils the groundnut yield will be low due to reduction in pod size and the number of pods per plant.
- Application of gypsum alleviates the detrimental effects of soil salinity by improving leaching of salts below the root zone.
- In addition to soil – texture, soil fertility is vitally important aspect of groundnut production.
- A moderate amount of organic matter (about 2%) will increase the water and nutrient - supplying capacity of the soil, especially the micro - nutrients like zinc, copper, iron, manganese, boron and molybdenum to meet the plant needs.
- Adequate supply of calcium in the soil is very essential for the production of well formed groundnut pods with sound and mature kernels.
- In tropical and subtropical conditions of India, groundnut is extensively grown in light - textured red sandy, red loamy, alluvial and coastal - alluvial soils as well as on mixed black and red and medium black soils.
- Both bunch (more than 50%) and runner (about 80%) type of groundnuts are grown on sandy, sandy - loam and mixed red and black soils in Southern India .
- Groundnut is also grown on medium black soils, deep alluvial loams and on sandy and gravelly soils of poor fertility with low organic matter content but the yields are low.