What the buyer is paying for
Staple length and strength come from the variety and the season. Cleanliness comes entirely from the picking, and it is where an ordinary crop and a well-handled one separate on price.
Contamination means anything that is not cotton lint: leaf trash, dried bracts, soil, jute fibre from sacks, hair, plastic, and — most damaging of all — coloured fibre from clothing or twine that shows up in the finished fabric and cannot be removed.
The practices that pay
Pick dry. Cotton picked with dew on it or after rain heats and yellows in the heap. Wait until the dew has lifted.
Pick fully opened bolls only. Immature lint drags down the grade of the whole lot.
Use cotton bags and cotton-lined baskets, never jute or plastic. Jute fibre in lint is one of the most penalised contaminants in Indian cotton, and it comes from the sack it was carried in.
Keep the pickers' clothing in mind. Coloured synthetic fibre and hair from the picking cloth end up in the lint.
Separate the grades as you pick. Clean upper-canopy cotton, and separately the stained, low, weather-damaged and insect-damaged bolls. Mixing them prices everything at the level of the worst.
Store off the ground, dry and covered, away from fuel and fertiliser that can taint it.
Timing the pickings
Two or three pickings, not one. Leaving the crop for a single clean sweep means the earliest, best-quality bolls sit exposed to weather, dust and pink bollworm for weeks.
Moisture
Cotton stored damp heats, yellows and loses grade. Dry it properly before heaping, and do not heap it deep while it is still warm.
After the last picking
Remove and destroy the stalks, the unopened bolls and the rosette flowers rather than leaving them. Pink bollworm carries over in exactly that material, and a field cleaned in March has far lower pressure the following October.
That is the cheapest pest control in the whole cotton calendar and it happens after the crop is sold, which is why it is skipped.
