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                                                                     Exhibit 5.1

                           [KIRKLAND & ELLIS LETTERHEAD]


                                   May 14, 2003

United Industries Corporation
and each of the Guarantors
of the Series D notes
2150 Schuetz Drive
St. Louis, Missouri 63146

     Re:  REGISTRATION STATEMENT ON FORM S-4

Ladies and Gentlemen

     We are issuing this opinion letter in our capacity as special legal
counsel to United Industries Corporation, a Delaware corporation (the
"Issuer"), and each of the other guarantors listed on Schedule A hereto (such
guarantors are hereinafter referred to as the "Guarantors" and the
Guarantors, together with the Issuer, are hereinafter referred to as the
"Registrants"), in connection with the proposed registration by the Issuer of
$235,000,000 in aggregate principal amount of the Issuer's 9 7/8% Series D
Senior Subordinated Notes due 2009 (the "Series D notes") pursuant to a
Registration Statement on Form S-4 filed with the Securities and Exchange
Commission (the "Commission") on May 1, 2003, under the Securities Act of
1933, as amended (the "Act") (such Registration Statement, as amended or
supplemented, is hereinafter referred to as the "Registration Statement").
The obligations of the Issuer under the Series D notes will be guaranteed by
the Guarantors (the "Guarantees"). The Series D notes and the Guarantees are
to be issued pursuant to an indenture (as amended and supplemented from time
to time, the "Indenture"), dated as of March 27, 2003, between the Issuer,
the Guarantors and U.S. Bank National Association, as trustee. The Series D
notes and the Guarantees are to be issued in exchange for and in replacement
of the Issuer's 9 7/8% Series B Senior Subordinated Notes due 2009 and 9 7/8%
Series C Senior Subordinated Notes due 2009 (together, the "Old Notes"), of
which $235,000,000 in aggregate principal amount is outstanding.

     In that connection, we have examined originals, or copies certified or
otherwise identified to our satisfaction, of such documents, corporate records
and other instruments as we have deemed necessary for the purposes of this
opinion, including (i) the Articles of Incorporation and By-Laws of the
Registrants, (ii) minutes and records of the corporate proceedings of the

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United Industries Corporation
and each of the Guarantors
May 14, 2003
Page 2


Registrants with respect to the issuance of the Series D notes and the
Guarantees, (iii) the Indenture, and  (iv) the Registration Statement.

     For purposes of this opinion, we have assumed the authenticity of all
documents submitted to us as originals, the conformity to the originals of all
documents submitted to us as copies and the authenticity of the originals of all
documents submitted to us as copies. We have also assumed the genuineness of the
signatures of persons signing all documents in connection with which this
opinion is rendered, the authority of such persons signing on behalf of the
parties thereto other than the Registrants and the due authorization, execution
and delivery of all documents by the parties thereto other than the Registrants.
As to any facts material to the opinions expressed herein which we have not
independently established or verified, we have relied upon statements and
representations of officers and other representatives of the Registrants and
others.

     Our opinion expressed below is subject to the qualifications that we
express no opinion as to the applicability of, compliance with, or effect of (i)
any bankruptcy, insolvency, reorganization, fraudulent transfer, fraudulent
conveyance, moratorium or other similar law affecting the enforcement of
creditors' rights generally, (ii) general principles of equity (regardless of
whether enforcement is considered in a proceeding in equity or at law), and
(iii) public policy considerations which may limit the rights of parties to
obtain certain remedies.

     Based upon and subject to the assumptions, qualifications, assumptions and
limitations and the further limitations set forth below, we are of the opinion
that when (i) the Registration Statement becomes effective, (ii) the Indenture
has been duly qualified under the Trust Indenture Act of 1939, as amended, and
(iii) the Series D notes have been duly executed and authenticated in accordance
with the provisions of the Indenture and duly delivered to the holders thereof
in exchange for the Old Notes, the Series D notes and the Guarantees will be
validly issued and binding obligations of the Issuer and Guarantors,
respectively.

     We hereby consent to the filing of this opinion with the commission as
Exhibit 5.1 to the Registration Statement. In giving this consent, we do not
thereby admit that we are in the category of persons whose consent is required
under Section 7 of the Act or the rules and regulations of the Commission.

     Our advice on every legal issue addressed in this letter is based
exclusively on the law of the State of New York, the General Corporation Law of
the State of Delaware and the Delaware case law decided thereunder, or the
federal law of the United States. We note that the issuer and certain of the
Guarantors are organized in jurisdictions other than the states of New York or
Delaware. We are not licensed to practice law in these other jurisdictions and
consequently, in giving this opinion we are relying on the opinions of Reinhart
Boerner Van Deuren S.C. and Thompson Coburn LLP as to certain matters under
Wisconsin and Missouri law, respectively.

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United Industries Corporation
and each of the Guarantors
May 14, 2003
Page 3


     This opinion is limited to the specific issues addressed herein, and no
opinion may be inferred or implied beyond that expressly stated herein. We
assume no obligation to revise or supplement this opinion should the present
laws of the States of New York or Delaware or the federal law of the United
States be changed by legislative action, judicial decision or otherwise.

     This opinion is furnished to you in connection with the filing of the
Registration Statement and is not to be used, circulated, quoted or otherwise
relied upon for any other purpose.

                                        KIRKLAND & ELLIS

                                        /s/ Kirkland & Ellis
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                                  SCHEDULE A

<table>
<caption>

    Guarantor                                            State of Incorporation
- ------------------                                       ----------------------
                                                      
Ground Zero Inc.                                                Missouri

Schultz Company                                                 Missouri

Sylorr Plant Corp.                                              Delaware

WPC Brands, Inc.                                                Wisconsin

</table>