Gypsum requirement for sodic land, application method, leaching, dhaincha, timeline.
How much gypsum per acre to reclaim sodic (usar) soil and how do I apply it?
RRam Naresh Yadav9mo ago · 279 views
5 Answers
🌾Farmer.in Krishi TeamExpert ✓9mo ago
For sodic (usar) soil the gypsum dose is not a fixed number; it should come from a lab gypsum requirement test based on your exchangeable sodium, and it commonly ranges widely from around 1 to 5 tonnes per acre or more for the top 15 cm. Apply finely ground gypsum, mix into the top soil, then irrigate heavily with good quality water to leach the displaced sodium down, so adequate drainage is essential. Growing dhaincha as a green manure after the first gypsum application speeds reclamation. Reclaiming usar land is a 2 to 3 year process, not one season, and you re-test as you go. Do not guess the gypsum dose; get the gypsum requirement from your soil testing lab or KVK and do not over apply.
SShiv Kumar8mo ago
Our usar patch in Raebareli came back over three years with lab dosed gypsum plus dhaincha and a drainage channel. Patience and drainage are everything.
RRam Sajivan Maurya8mo ago
Use finely powdered gypsum, not the coarse lumps. The first time I used coarse material it barely worked because it does not react. The fine powder mixed into the top soil before a heavy watering made a real difference, and I could see the white crust reducing over the seasons.
CChhotelal Patel7mo ago
Do not skip the drainage part. My neighbour added gypsum and watered heavily but had no outlet, so the salty water just sat there and the soil stayed bad. The sodium you push off has to leave the field somewhere. We dug a field drain first and only then the reclamation started moving.
RRam Avadh Yadav7mo ago
Do not expect one application to fix usar land in a season. Our patch in Pratapgarh took the lab dosed gypsum, dhaincha and a drain over nearly three years before crops came good. Re-testing each year told us we were moving in the right direction.