Exhibit (d)(18)

STOCK PURCHASE AGREEMENT

THIS STOCK PURCHASE AGREEMENT, dated as of September 29, 2003 (this
"Agreement"), is made by and among Seminis Merger Corp., a Delaware corporation
(the "Company"), G. Carl Ball, the G. Carl Ball Family Foundation, G. Dexter
Ball, Margaret D. Ball, G. Victor Ball Marital Trust and Vivian Elledge Ball GST
Exempt Trust UAD 12/21/92 (each a "Seller" and collectively the "Sellers").

WHEREAS, at the Effective Time of the Merger (each as defined
below), the Company shall merge with and into Seminis, Inc. ("Seminis")and the
separate corporate existence of the Company shall thereupon cease, Seminis will
be the surviving corporation in the Merger and after the Effective Time of the
Merger, all references to the Company in this Agreement shall be to Seminis,
Inc.;

WHEREAS, each Seller is an owner of shares of Class B Redeemable
Preferred Stock (the "Class B Preferred Stock") of Seminis as set forth on
Exhibit A hereto (the "Sale Shares"), and each Seller desires to sell and the
Company desires to purchase each Seller's right, title and interest in and to
the Sale Shares (the "Stock Purchase") in exchange for $950.00 per share of
Class B Preferred Stock and an aggregate purchase price of $23,750,000 for all
the Sale Shares;

WHEREAS, in connection with the closing of the Merger, the Company
is required to pay to each Seller an amount equal to all accrued and unpaid
dividends on the Class B Preferred Stock as of the payment date (determined in
accordance with the certificate of designations of the Class B Preferred Stock)
immediately preceding the closing date of the Merger (as defined below); and

WHEREAS, in connection with this Agreement, the Company shall pay
all accrued and unpaid dividends on the Class B Preferred Stock from such last
payment date through the Closing Date (as defined below);

NOW, THEREFORE, in consideration of the representations, warranties,
covenants and agreements contained in this Agreement, the parties hereto agree
as follows:

ARTICLE I

CERTAIN DEFINITIONS

As used in this Agreement, the following terms shall have the respective
meanings set forth below:

"Agreement" shall have the meaning set forth in the preamble.

"Class B Preferred Stock" shall have the meaning set forth in the
recitals.

"Closing" shall have the meaning set forth in Section 2.1.

"Closing Date" shall have the meaning set forth in Section 2.1.

"Company" shall have the meaning set forth in the preamble.

"Effective Time" shall mean the time the Merger becomes effective, which
will be either the time the certificate of merger with respect to the Merger is
duly filed with the Secretary of State of Delaware or at such a later date and
time as the parties shall agree and as shall be specified in such certificate of
merger.

"Governmental Entity" means any federal, state, local or foreign court or
tribunal or administrative, governmental or regulatory body, agency or
authority.

"Lien" means any security interests, liens, claims, charges, title
defects, deficiencies or exceptions, mortgages, pledges, rights of first
refusal, options, conditional sales or other title retention agreements,
covenants, conditions or other similar restrictions (including restrictions on
transfer) or other encumbrances of any nature whatsoever (other than
restrictions imposed generally by state and federal securities laws with respect
to unregistered securities).

"Merger" shall mean the merger of the Company with and into Seminis, with
Seminis, as the surviving corporation, as provided in the Merger Agreement (as
defined below).

"Merger Agreement" means the Agreement and Plan of Merger, dated as of May
30, 2003, as amended, by and among Seminis Acquisition LLC, the Company and
Seminis.

"Sale Shares" shall have the meaning set forth in the recitals.

"Seller" and "Sellers" shall each have the meaning set forth in the
preamble.

"Stock Purchase" shall have the meaning set forth in the recitals.

ARTICLE II

THE STOCK PURCHASE

Section 2.1. The Closing. The closing of the Stock Purchase (the
"Closing") will be held at the offices of Milbank, Tweed, Hadley & McCloy LLP, 1
Chase Manhattan Plaza, New York, New York, at 10:00 a.m. New York City time (or
such other place as the parties hereto may agree) on the closing date of the
Merger (the "Closing Date") after satisfaction or waiver of the conditions set
forth in Article V.

Section 2.2. Purchase and Sale. Subject to the terms and conditions
set forth herein, at the Closing, each Seller shall sell to the Company all of
such Seller's right, title and interest in and to the Sale Shares as set forth
opposite such Seller's name on Exhibit A, free and clear of any Lien; including
without limitation, any rights of Sellers to accrued but unpaid dividends as of
the Closing Date. The Company agrees that in the event of overpayment of the
accrued but unpaid dividends, it will not seek reimbursement thereof from the
Sellers.

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Section 2.3. Delivery of Sale Shares. At the Closing, each Seller
shall deliver or cause to be delivered to the Company:

(a) one or more stock certificates representing in the aggregate
such Seller's shares of Class B Preferred Stock as set forth on Exhibit A, duly
endorsed in blank for transfer or accompanied by duly executed stock powers and
all applicable stock transfer stamps and other instruments requisite for proper
transfer, all in proper form; and

(b) upon receipt of the cash payments as set forth in Section 2.4,
each Seller agrees that (i) all accrued and unpaid dividends through the Closing
Date have been fully satisfied as part of the delivery of the Sale Shares and
(ii) Seller shall have no other right with respect to the Sale Shares other than
the right to receive the payments contemplated by this Agreement.

Section 2.4. Payment. At the Closing, the Company shall pay to each
Seller by wire transfer of immediately available funds (to the account
designated by each Seller in writing not less than three days prior to Closing):

(a) $950.00 for each share of Class B Preferred Stock owned by each
Seller (as set forth on Exhibit A hereto);

(b) in connection with the Merger, but separately from the Stock
Purchase hereunder, all accrued and unpaid dividends on the Class B Preferred
Stock as of the payment date (determined in accordance with the certificate of
designations of the Class B Preferred Stock) immediately preceding the closing
date of the Merger (as set forth on Exhibit B hereto); and

(c) in connection with this Agreement, all accrued and unpaid
dividends on the Class B Preferred Stock from such last payment date through the
Closing Date (as set forth on Exhibit B hereto).

ARTICLE III

REPRESENTATIONS AND WARRANTIES OF SELLERS

Each Seller, severally and not jointly, hereby represents and warrants to
the Company as follows:

Section 3.1. Authority. Each Seller has all necessary power and
authority to execute and deliver this Agreement and to consummate the
transactions contemplated hereby. The execution and delivery of this Agreement
and the consummation of the transactions contemplated hereby have been duly and
validly authorized by each Seller, who is not an individual, and no other
proceeding or approval on the part of any Seller is necessary to authorize this
Agreement or to consummate the transactions contemplated hereby. This Agreement
has been duly and validly executed and delivered by each Seller and, assuming
due and valid authorization, execution and delivery by the Company, constitutes
the valid, legal and binding obligation of each Seller, enforceable against each
Seller in accordance with its terms, except as enforceability may be restricted,
limited or delayed by applicable bankruptcy,

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insolvency, fraudulent conveyance, or other laws affecting creditor's rights
generally, and except as enforceability is subject to general principles of
equity.

Section 3.2. Ownership of Stock. On the date hereof and as of the
Closing Date, each Seller is the owner, beneficially and of record, of the
shares as set forth on Exhibit A, free and clear of any Lien and will transfer
to the Company good and valid title to such shares free and clear of any Lien.

ARTICLE IV

REPRESENTATIONS AND WARRANTIES OF PURCHASER

The Company hereby represents and warrants to each Seller as follows:

Section 4.1. Organization, Good Standing. The Company is a
corporation duly organized, validly existing and in good standing under the laws
of the State of Delaware.

Section 4.2. Authorization. The Company has the corporate power and
authority to enter into this Agreement and to consummate the transactions
contemplated hereby. All actions on the part of the Company necessary for the
authorization, execution, delivery and performance of this Agreement and the
consummation of the transactions contemplated hereby have been or will be taken
prior to the Closing Date, and this Agreement constitutes the legal, valid and
binding obligation of the Company, enforceable against it in accordance with its
terms, except as enforceability may be restricted, limited or delayed by
applicable bankruptcy, insolvency, fraudulent conveyance, or other laws
affecting creditor's rights generally, and except as enforceability is subject
to general principles of equity.

ARTICLE V

CONDITIONS TO CONSUMMATION OF THE STOCK PURCHASE

Section 5.1. Conditions to Performance by Sellers. The obligation of
each Seller to consummate the Stock Purchase is subject to the satisfaction (or
waiver) at or prior to the Closing Date of each of the following conditions:

(a) Accuracy of Representations and Warranties. The representations
and warranties made by the Company herein shall be true and correct in all
respects on the date hereof and on the Closing Date.

(b) Closing of the Merger. The closing of the Merger shall occur
substantially concurrently with the Closing.

(c) Statutes; Court Orders. No statute, rule, regulation, executive
order, decree, ruling or injunction shall have been enacted, entered,
promulgated, issued or enforced by any Governmental Entity that prohibits,
restrains, enjoins, precludes or restricts the consummation of the Stock
Purchase or the Merger.

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Section 5.2. Conditions to Performance by the Company. The
obligation of the Company to consummate the Stock Purchase is subject to the
satisfaction (or waiver) at or prior to the Closing Date of each of the
following conditions:

(a) Accuracy of Representations and Warranties. The representations
and warranties made by each Seller herein shall be true and correct in all
respects on the date hereof and on the Closing Date.

(b) Closing of the Merger. The closing of the Merger shall occur
substantially concurrently with the Closing.

ARTICLE VI

TERMINATION; AMENDMENT; WAIVER

Section 6.1. Termination. This Agreement may be terminated and the
Stock Purchase may be abandoned at any time prior to the Closing:

(a) if the Merger Agreement is terminated; or

(b) by mutual written consent of the Company and Sellers; or

(c) by the Company or Sellers, if any Governmental Entity shall have
enacted, entered, promulgated, issued or enforced a final statute, rule,
regulation, executive order, decree, ruling or injunction (which statute, rule,
regulation, executive order, decree, ruling or injunction the Company shall use
its reasonable best efforts to reverse, overturn or lift and each Seller shall
use reasonable best efforts to assist the Company to reverse, overturn or lift)
or taken any other final action restraining, enjoining or otherwise prohibiting
the Stock Purchase or the Merger and such order, decree, ruling or other action
is or shall have become final.

Section 6.2. Effect of Termination. In the event of the termination
and abandonment of this Agreement pursuant to Section 6.1, written notice
thereof shall forthwith be given to the other party or parties specifying the
provision hereof pursuant to which such termination is made, and this Agreement
shall forthwith become void and have no effect, without any liability on the
part of any party hereto or its affiliates, directors, officers or stockholders;
provided, however, that nothing contained in this Section 6.2, shall relieve any
party from liability for any willful and material breach of this Agreement.

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Section 6.3. Fees and Expenses. All costs and expenses incurred in
connection with this Agreement shall be paid by the party incurring such
expenses.

Section 6.4. Amendment; Waiver. No amendment, waiver, change,
modification or discharge of any provision of this Agreement shall in any event
be effective unless the same shall be in writing and signed by all parties
hereto.

ARTICLE VII

MISCELLANEOUS

Section 7.1. Entire Agreement; Assignment. This Agreement (including
Exhibit A hereto) and the Certificate of Designations with respect to the Class
B Preferred Stock constitute the entire agreement among the parties hereto with
respect to the subject matter hereof and supersedes all other prior agreements
and understandings, both written and oral, between the parties hereto with
respect to the subject matter hereof. This Agreement shall be binding upon and
inure to the benefit of the parties hereto and their respective heirs,
executors, legal representatives, successors and assigns.

Section 7.2. Severability. If any provision of this Agreement, or
the application thereof to any person or circumstance, is held invalid or
unenforceable, the remainder of this Agreement, and the application of such
provision to other persons or circumstances shall not be affected thereby, and
to such end, the provisions of this Agreement are agreed to be severable. Upon
such determination that any provision is invalid or unenforceable, the parties
hereto shall negotiate in good faith to modify this Agreement so as to effect
the original intent of the parties hereto as closely as possible in a mutually
acceptable manner.

Section 7.3. Notices. All notices, requests, claims, demands and
other communications hereunder shall be in writing (including by facsimile with
written confirmation thereof) and unless otherwise expressly provided herein,
shall be delivered during normal business hours by hand, by Federal Express or
other nationally recognized overnight commercial delivery service, or by
facsimile notice, confirmation of receipt received, addressed as follows, or to
such other address as may be hereafter notified by the respective parties
hereto:

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(a) If to the Sellers:

To: Mr. G. Carl Ball
708 Crescent Boulevard
Glen Ellyn, Illinois 60137
Facsimile: