Cal. Government Code § 51245

If either the landowner or the city or county desires in any year not to renew the contract, that party shall serve written notice of nonrenewal of the contract upon the other party in advance of the annual renewal date of the contract. Unless such written notice is served by the landowner at least 90 days prior to the renewal date or by the city or county at least 60 days prior to the renewal date, the contract shall be considered renewed as provided in Section 51244 or Section 51244.5. Upon receipt by the owner of a notice from the county or city of nonrenewal, the owner may make a written protest of the notice of nonrenewal. The county or city may, at any time prior to the renewal date, withdraw the notice of nonrenewal. Upon request by the owner, the board or council may authorize the owner to serve a notice of nonrenewal on a portion of the land under a contract. No later than 20 days after a city or county receives a notice of nonrenewal from a landowner, serves a notice of nonrenewal upon a landowner, or withdraws a notice of nonrenewal, the clerk of the board or council, as the case may be, shall record with the county recorder a copy of the notice of nonrenewal or notice of withdrawal of nonrenewal.