I believe there are a few cooperative factories in the Nilgiris… in northern India the plantation model dominates. There are a few worker-run plantations, but they generally run into technical problems, due to lack of training… often these sorts of plantations happen when the management abandons it due to financial issues or some other setback, leaving the pluckers and processors to fend for themselves.
In Sri Lanka they experimented with nationalized tea gardens, but had trouble turning a profit for various reasons until the industry was privatized again.