<Page> UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K (X) CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 June 14, 2002 UNITED INDUSTRIES CORPORATION (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER) DELAWARE 333-76055 43-1025604 (STATE OR OTHER JURISDICTION OF (COMMISSION (I.R.S EMPLOYER INCORPORATION OR ORGANIZATION) FILE NO.) IDENTIFICATION NO.) 8825 PAGE BOULEVARD ST. LOUIS, MISSOURI 63114 (ADDRESS OF PRINCIPAL EXECUTIVE OFFICE, INCLUDING ZIP CODE) (314) 427-0780 (REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE) <Page> ITEM 1. CHANGES IN CONTROL OF REGISTRANT. None. ITEM 2. ACQUISITION OR DISPOSITION OF ASSETS. None. ITEM 3. BANKRUPTCY OR RECEIVERSHIP. None. ITEM 4. CHANGES IN REGISTRANT'S CERTIFYING ACCOUNTANT. None. ITEM 5. OTHER EVENTS. On June 17, 2002, United Industries Corporation and Bayer CorpScience consummated the strategic partnership that the parties entered into on June 7, 2002. United Industries Corporation issued a press release on June 7, 2002 relating to the strategic partnership, a copy of which is filed herewith as Exhibit 99 and incorporated herein by reference. ITEM 6. RESIGNATIONS OF REGISTRANT'S DIRECTORS. None. ITEM 7. FINANCIAL STATEMENTS AND EXHIBITS. None. (a) Financial statements of businesses acquired: Not applicable. (b) Pro forma financial information: Not applicable. (c) Exhibits: Exhibit 99 Press Release dated June 7, 2002 ITEM 8. CHANGE IN FISCAL YEAR. None. ITEM 9. REGULATION FD DISCLOSURE. None. 2 <Page> SIGNATURES PURSUANT TO THE REQUIREMENTS OF THE SECURITIES AND EXCHANGE ACT OF 1934, THE REGISTRANT HAS DULY CAUSED THIS REPORT TO BE SIGNED ON ITS BEHALF BY THE UNDERSIGNED THEREUNTO DULY AUTHORIZED. UNITED INDUSTRIES CORPORATION DATED: JULY 1, 2002 BY: /s/ DANIEL J. JOHNSTON ---------------------- NAME: DANIEL J. JOHNSTON TITLE: EXECUTIVE VICE PRESIDENT AND CHIEF FINANCIAL OFFICER 3