1. They are harvested 3 to 4 weeks after sowing,
2. Harvesting should be done, when the leaves are immature and tender, but large enough.
3. Old leaves are bitter and unfit for consumption.
First cutting 3 to 4 weeks after sowing. Leaves are cut manually from the base. It gives 3 to 4 pickings at 15 days interval.
Uprooting is done 3-4 weeks after sowing. If clippings are to be taken then first clipping 25 to 30 days after sowing and other at 20 to 25 days interval. Total 2-4 clippings.
When common methi is taken, the younger shoots are nipped off in about 3 weeks after sowing. Later on the whole plant is often pulled out, bunched and marketed. The kasuri methi gives a number of cutting. First cutting 25-30 days after sowing.
Subsequent cuttings taken at 12 to 15 days interval. After 2-3 cuttings plants are left for seeding.
Reference : agriinfo