California Code, Civil Code - CIV § 4750

(a) For the purposes of this section, “personal agriculture” has the same definition as in Section 1940.10.

(b) Any provision of a governing document, as defined in Section 4150, shall be void and unenforceable if it effectively prohibits or unreasonably restricts the use of a homeowner's backyard for personal agriculture.

(d) This section applies only to yards that are designated for the exclusive use of the homeowner.

(e) This section shall not prohibit a homeowners' association from applying rules and regulations requiring that dead plant material and weeds, with the exception of straw, mulch, compost, and other organic materials intended to encourage vegetation and retention of moisture in the soil, are regularly cleared from the backyard.