How long can i wait before doing meniscus repair surgery?

No definite answer: Meniscus tears that are repairable should be repaired as expeditiously as possible. No one can know for certain when or if another injury will occur. Further injury may convert a repairable tear to a tear that cannot be repaired but only partially removed. While waiting for a likely repair, it is prudent to greatly limit any activities that put the knee and meniscus at risk for further injury.

Swelling down: As soon as swelling is down.