UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K/A

(Amendment No. 1)

For the fiscal year ended September 27, 2003

Commission File Number 0-20242

CENTRAL GARDEN & PET COMPANY

(Exact name of registrant as specified in its charter)

3697 Mt. Diablo Boulevard, Lafayette, California 94549

(Address of principal executive offices) (Zip Code)

Telephone Number: (925) 283-4573

SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:

SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT:

Common Stock

(Title of Class)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x.    No  ¨.

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§ 229.405 of this chapter) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ¨

Indicate by check mark whether the registrant is an accelerated filer (as defined in Exchange Act Rule 12b-2).    Yes  x.    No  ¨.

At March 29, 2003, the aggregate market value of the registrant’s Common Stock and Class B Stock held by non-affiliates of the registrant was approximately $354,478,000 and $1,156,000 respectively.

At December 1, 2003, the number of shares outstanding of the registrant’s Common Stock was 18,268,968. In addition, on such date the registrant had outstanding 1,654,462 shares of its Class B Stock, which are convertible into Common Stock on a share-for-share basis.

DOCUMENTS INCORPORATED BY REFERENCE

Definitive Proxy Statement for the Company’s 2004 Annual Meeting of Stockholders - Part III of this Form 10-K/A.

INTRODUCTORY NOTE

This amendment on Form 10-K/A is being filed to correct certain section references in “Part II - Item 9A. Controls and Procedures” and to file new officers’ certifications. This amendment is not intended to update other information presented in this annual report as originally filed, except where specifically noted.

“Part II - Item 9A. Controls and Procedures” in the original Form 10-K is deleted in its entirety and replaced with the following:

Item 9A. Controls and Procedures

(a) Evaluation of disclosure controls and procedures. Our Chief Executive Officer and Chief Financial Officer have reviewed, as of the end of the period covered by this report, the “disclosure controls and procedures” (as defined in the Securities Exchange Act of 1934 Rules 13a-15(e) and 15d-15(e)) that ensure that information relating to the Company required to be disclosed by us in the reports that we file or submit under the Exchange Act, is recorded, processed, summarized and reported in a timely and proper manner. Based upon this review, we believe that the controls and procedures in place are effective to ensure that information relating to the Company that is required to be disclosed by us in the reports that we file or submit under the Exchange Act is properly disclosed as required by the Exchange Act and related regulations.

(b) Changes in internal controls. There were no significant changes in our internal control over financial reporting that occurred during our last fiscal year that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

“Part IV - Item 15. Exhibits, Financial Statement Schedules and Reports on Form 8-K” in the original Form 10-K is deleted in its entirety and replaced with the following:

PART IV

Item 15. Exhibits, Financial Statement Schedules and Reports on Form 8-K

Independent Auditors’ Report

Consolidated Balance Sheets

Consolidated Statements of Income

Consolidated Statements of Shareholders’ Equity

Consolidated Statements of Cash Flows

Notes to Consolidated Financial Statements

All other schedules are omitted because of the absence of conditions under which they are required or because the required information is included in the consolidated financial statements or notes thereto.

See attached Exhibit Index.

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We furnished the following report on Form 8-K during the fourth quarter of fiscal 2003:

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: April 1, 2004

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EXHIBIT INDEX

Set forth below is a list of exhibits that are being filed or incorporated by reference into this Form 10-K/A:

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