How Soil Type Affects Plant Nutrition
Soil is the foundation of farming. But did you know that the type of soil – especially whether it is acidic or alkaline – can decide how well your crops absorb nutrients?
Soil type has a vital function in nutrient availability and absorption by plants. Among different soil types, alkaline and acidic soils show distinctive challenges that extensively influence nutrient uptake, time and again leading to deficiencies or toxicities that can have an effect on plant development and yield.
What is Soil pH?
Soil pH informs us how acidic or alkaline the soil is. It is calculated on a scale from 0 to 14 –
- pH < 7 = Acidic soil
- pH = 7 = Neutral soil
- pH > 7 = Alkaline soil
Plants raise best in slightly acidic to neutral soils (pH 6.0-7.5). Outer this range, several nutrients become unavailable, even if they are there in the soil.
Acidic Soils in India
Where Found?
- High rainfall areas: Northeast India, Odisha, Jharkhand, Chhattisgarh, Kerala, West Bengal, and parts of Karnataka.
What Happens in Acidic Soils?
- Aluminum (Al³⁺) and Manganese (Mn²⁺) become too much available and toxic to plants.
- Calcium (Ca), Magnesium (Mg), and Potassium (K) get eroded.
- Phosphorus (P) gets locked up with iron and aluminum, making it unavailable.
Real Impact:
- In Odisha and Jharkhand, farmers growing turmeric and rice often see yellowing leaves and poor root growth due to aluminum toxicity and phosphorus deficiency.
What Can Farmers Do?
- Add lime (calcium carbonate) to reduce acidity.
- Use organic manure to improve soil health.
- Grow acid-tolerant crops like tea, oats, millets, and turmeric.
Alkaline Soils in India
Where Found?
- Dry regions: Rajasthan, Gujarat, Punjab, Haryana, Uttar Pradesh, and Maharashtra.
What Happens in Alkaline Soils?
- Micronutrients such as Iron (Fe), Zinc (Zn), Manganese (Mn) become insoluble and unavailable.
- Phosphorus gets locked up with calcium.
- In sodic soils, too much sodium harms plant roots and soil structure.
Real Impact:
- In parts of Uttar Pradesh and Haryana, wheat and sugarcane show yellowing leaves due to iron and zinc deficiency.
What Can Farmers Do?
- Apply gypsum to reduce sodium levels.
- Use chelated micronutrients (special forms that plants can absorb).
- Add organic compost to boost soil life and structure.
What Indian Research Says –
ICRISAT’s Bhoochetana Program:
- In Karnataka and Odisha, ICRISAT helped over 4 million farmers improve yields by using soil test-based nutrient management.
- Farmers saw 20-66% increase in crop yields and better soil health.
Soil Nutrient Mapping:
- ICRISAT analyzed over 100,000 soil samples and found widespread deficiencies of zinc, boron, and sulfur, especially in dry land and acidic soils.
ICAR’s Recommendations:
- Promote Integrated Nutrient Management (INM): Combine fertilizers with organic matter.
- Use soil health cards to guide fertilizer use based on actual soil needs.
Summary Table –
| Soil Type: | Common Regions: | Problems: | Solutions: |
| Acidic | NE India, Odisha, Kerala | Al toxicity, P lock-up, nutrient leaching | Lime, organic manure, acid-tolerant crops |
| Alkaline | Rajasthan, Gujarat, UP | Micronutrient deficiency, P lock-up, Na toxicity | Gypsum, chelated nutrients, compost |
Even if your soil has nutrients, your plants may not be able to use them if the pH is too high or too low. That’s why knowing your soil pH and managing it properly is one of the smartest things you can do for better crops and a healthier environment.
References –
https://oar.icrisat.org/9781/1/Bhoochetana-Book-Chapter-3.pdf
https://beta.icrisat.org/storage/file-managers/Soil-Health.pdf