<PAGE>
                                                                    Exhibit 10.4

                                SUPPLY AGREEMENT
                                ----------------

     THIS AGREEMENT entered into effective as of the 24/th/ day of November,
2003 (the "Effective Date"), between CONAGRA INTERNATIONAL FERTILIZER COMPANY, a
Delaware corporation ("Seller") and UNITED AGRI PRODUCTS, INC., a Delaware
corporation ("Buyer").

RECITALS:
---------

     (a)  Buyer is engaged in the sale of fertilizer products and desires to
          purchase its source of supply of such products from Seller.

     (b)  Seller is engaged in the sale of fertilizer products and desires to
          sell such products to Buyer.


AGREEMENT:
----------

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
and agreements set forth herein, the parties agree as follows:

     1.   Definitions. Unless the context requires otherwise, as used in this
Agreement, certain words have the meanings as follows:

     (a)  "Year" - a year shall mean a calendar year during the term of this
          Agreement.

     (b)  "Month" - a month shall mean a calendar month during the term of this
          Agreement.

     (c)  "Product" - any one of the various agricultural fertilizer materials
          as listed on Exhibit "A" of this Agreement.

     (d)  "Products" - collectively, all of the various agricultural fertilizer
          materials listed on Exhibit "A" of this Agreement.

     2.   Term. The initial term of this Agreement shall commence on the
Effective Date and shall continue in full force and effect for a period of five
(5) years. This Agreement shall automatically renew from year to year after the
initial term, unless terminated by either party on not less than one hundred
eighty (180) days' written notice prior to the end of the initial or any renewal
term of this Agreement.

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     3.   Quantity. Subject to the parties mutually agreeing to prices and
producer availability, Buyer shall purchase from Seller and Seller shall sell to
Buyer that amount of Products equal to its historical purchases from Seller
(approximately seventy percent (70%) of Buyer's requirements of Products).

     4.   Price.

     4.1  Bulk Product. The price for bulk Product sold under this Agreement
          shall be a mutually agreed upon market price based on market
          conditions existing at the time of sale and shall be similar to prices
          for Product sold by Seller to third parties purchasing similar
          quantities of Product, types of Product and during similar time
          periods.

     4.2  Back-to-Back Transactions. The price for Products sold to Buyer in
          back-to-back transactions shall be an amount equal to the price Seller
          paid to acquire such Products, plus $1.00 per ton.

     4.3  Purchases from Seller's Mix Plants. Seller shall be responsible for
          supplying raw materials to Seller's mix plants (Denison, Iowa;
          Irvington, Iowa; Franklin, Minnesota; Pekin, Illinois; Kentland,
          Indiana; and Yoder, Indiana) at Seller's cost.

     4.4  Seller/Buyer Imperial Joint Venture. Seller shall be responsible for
          supplying raw materials to the Imperial Joint Venture between Seller
          and Buyer at Seller's cost.

     5.   Payment and Remedies. Subject to the terms of this Section 5, for the
     first nine (9) months from and after the Effective Date each payment due
     from Buyer hereunder shall be paid within sixty (60) days from the date of
     delivery of each invoice, or such other term mutually agreed to by the
     parties. After such initial nine (9) month period, each payment due from
     Buyer hereunder shall be paid within thirty (30) days from the date of each
     invoice or such other term mutually agreed to by the parties. If Buyer
     fails to pay when due any amount owed to Seller under this Agreement, a
     service charge will be imposed by Seller equal to the greater of one and
     one-half percent (11/2%) per month or the highest rate permitted by law on
     the outstanding amount for each monthly portion thereof that such amount is
     overdue. Notwithstanding the foregoing provisions, and unless the parties
     mutually agree otherwise:

     (a)  If, during the first nine (9) months after the date hereof:

               (i)  Buyer has any invoices over sixty (60) days past due or
                    total outstanding invoices at any time exceeding
                    $90,000,000, then, upon written notice to Buyer advising of
                    the default (a "Notice"), Seller shall have the right to
                    discontinue shipment of Products to Buyer. Buyer shall then
                    have forty eight (48) hours after the time of delivery of
                    the Notice to cure its default.

                                        2

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                    If at the end of this forty eight (48) hour cure period
                    Buyer has failed to cure its default, Seller shall have the
                    right to terminate this Agreement and accelerate all amounts
                    hereunder then due and owing by Buyer to Seller or suspend
                    shipments of Product to Buyer until Buyer cures its default.

               (ii) Buyer is in material default under its Credit Agreement
                    dated as of November 24, 2003 by and among Buyer, United
                    Agri Products Canada, Inc., the other persons designated as
                    "Credit Parties" on the signature pages thereto, the
                    financial institutions who are or hereafter become parties
                    to the Credit Agreement as Lenders, General Electric Capital
                    Corporation, as the initial L/C Issuer and as Agent and GE
                    Canada Finance, as Canadian Agent (the "Credit Agreement")
                    but is otherwise in compliance with the terms of this
                    Agreement, then Buyer shall be immediately placed on thirty
                    (30) day terms until the default under the Credit Agreement
                    is cured. In such case, Buyer shall simultaneously send to
                    Seller copies of all notices Buyer sends to General Electric
                    Capital Corporation pursuant to and in connection with the
                    Credit Agreement.

     (b)  If, after such initial nine (9) month period:

               (i)  Buyer is not in compliance with the then-existing credit
                    terms under this Agreement, then, upon Notice to Buyer,
                    Seller shall have the right to discontinue shipment of
                    Products to Buyer. Buyer shall then have forty eight (48)
                    hours from and after the time of delivery of the Notice to
                    cure its default. If at the end of this forty eight (48)
                    hour cure period Buyer has failed to cure its default,
                    Seller shall have the right to terminate this Agreement and
                    accelerate all amounts hereunder then due and owing by Buyer
                    to Seller or suspend shipments of Product to Buyer until
                    Buyer cures its default. Buyer shall have the foregoing cure
                    rights a maximum of three (3) times during the term of this
                    Agreement. After such cure rights have been extended three
                    (3) times, Seller shall have the right to terminate this
                    Agreement upon notice to Buyer and accelerate all amounts
                    hereunder then due and owing by Buyer to Seller.

     6.   Schedules.

     6.1  Shipping Schedule. During the term of this Agreement, Buyer shall, not
          later than June 1 and December 1 of each Year, provide Seller with an
          itemized monthly shipping schedule for the Products covering its
          anticipated purchases of Products for the following six (6) Months
          ("Estimates"). Buyer shall use its commercially reasonable efforts to
          update such Estimates Monthly.

     6.2  Order Placement. Detailed orders for shipments of Products are to be
          placed with Seller consistent with past practices (including
          quantities of Product and time for delivery), taking into
          consideration current market conditions and available transportation
          resources and in quantities substantially consistent with the

                                        3

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          Estimates. All orders for Products shall be made by Buyer using the
          form of purchase order attached hereto as Exhibit "B" ("Purchase
          Order"). The parties agree that this Agreement will be automatically
          incorporated into every Purchase Order documenting the sale of
          Products under this Agreement. Each Purchase Order is binding upon the
          parties, and will supplement this Agreement, to the extent that the
          Purchase Order is not inconsistent with this Agreement. In the

                                        4

<PAGE>

          event of any inconsistencies between this Agreement and the Purchase
          Order, the terms and conditions of this Agreement will supersede the
          inconsistent provisions of the Purchase Order. The remaining
          provisions of the Purchase Order which are not inconsistent with this
          Agreement will remain effective.

     7.   Deliveries. Seller will ship the Product in packaging as reasonably
requested by Buyer and agreed to by Seller to Buyer's facility or designated
storage space. Title and risk of loss shall pass to Buyer as the Product is
progressively loaded on board carrier at such shipping point. All Products shall
be sold FOB Seller's terminals, except as otherwise agreed by the parties and
reflected in the Purchase Order for such sale. Seller will route all shipments
where transportation is Seller's responsibility; however, Buyer may issue
specific routing instructions and assume any additional cost associated with
same. Any subsequent charges due to action initiated by a party hereto such as,
but not limited to, diversions, stopovers and demurrage, or charges for returned
Product, are for that party's account. All shipments will be made on a
commercial straight bill of lading. Seller will furnish Buyer an original and,
upon request, one (1) copy of the invoice. Buyer shall promptly receive and
unload Products. Demurrage or car detention charges shall be imposed in
accordance with Seller's general policy as in effect from time to time. The
foregoing delivery terms set forth in Section 7 are subject to change based on
the mutual agreement of the parties.

     8.   Warranties.

     (a)  Seller warrants that the Products covered by this Agreement will meet
          the specifications for such Products as reflected on Seller's then
          current Product data sheets, that Seller will convey good title
          thereto, and that such Products shall be delivered free from any
          lawful security interest or encumbrance.

     (b)  EXCEPT AS SET FORTH IN SECTION 8(a) ABOVE, NEITHER SELLER NOR ANY
          MANUFACTURER OR OTHER SELLER (OR ANY AGENT ON THEIR BEHALF, SUCH
          AGENTS HAVING NO AUTHORITY IN SUCH RESPECT), MAKES ANY WARRANTIES,
          GUARANTEES, OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED,
          OR BY USAGE OF TRADE, STATUTORY OR OTHERWISE, WITH REGARD TO THE
          PRODUCTS SOLD, OR THE USE OF THE PRODUCTS, INCLUDING, BUT NOT LIMITED
          TO MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, USE OR
          ELIGIBILITY OF THE PRODUCTS FOR ANY PARTICULAR TRADE USAGE, ALL OF
          WHICH ARE HEREBY EXPRESSLY DISCLAIMED.

     (c)  Buyer and the ultimate consumer of the Products assume all risks and
          liabilities whatsoever resulting from transportation, handling,
          storage, use, and disposal of the Products after delivery of the
          Products, whether the Products are used singly or in combination with
          other substances.

                                        5

<PAGE>

     (d)  Except as otherwise expressly provided in this Agreement, no claim of
          any kind whatsoever, whether arising in contract, tort, negligence,
          breach of warranty, strict liability, or under any other legal theory,
          as to Products delivered or for non-delivery of Products shall be
          greater in amount than the purchase price of the Products with respect
          to which damages are claimed, and Seller's sole liability to Buyer, if
          any, and Buyer's sole remedy in respect of any such claim, shall in no
          event exceed such purchase price. Seller may satisfy any such
          liability at its option either by (i) replacing such Products, or (ii)
          refunding to Buyer (by cash or credit) the purchase price of such
          Products.

     (e)  Under no circumstances shall either party or their respective
          affiliates be liable to the other party for consequential, incidental,
          special or indirect damages.

     (f)  Any advice furnished by Seller or its agents with reference to the use
          of the Products is given gratis and Seller assumes no obligation or
          liability for the advice given or the results obtained and any such
          Products advice furnished by Seller shall not constitute a
          representation, warranty or guarantee as to any matter, all such
          advice being given and accepted at Buyer's or the ultimate consumers'
          risk. No statements or suggestions contained in Seller's or its
          affiliates' literature are to be construed as inducements to infringe
          any patent.

     9.   Indemnification.

     (a)  Buyer shall indemnify and hold Seller harmless against any liability,
          damage, loss, cost or expense (including reasonable attorneys' fees)
          arising out of Buyer's breach of its obligations under this Agreement
          as well as the transportation, storage, promotion, distribution, sale
          or use of the Products by Buyer or any negligent or willful act or
          omission by Buyer, including those resulting from any property damage
          (including, but not limited to, any kind of environmental damage or
          contamination or a release or spill or exposure in or to the
          environment or persons), personal injury (including death) to any
          person, including employees, servants, or agents of Buyer, except to
          the extent and in the proportion caused by any breach of this
          Agreement by Seller or the failure of any Products supplied hereunder
          to comply with its current data sheet.

     (b)  Seller shall indemnify and hold Buyer harmless against any liability,
          damage, loss, cost or expense (including reasonable attorneys' fees)
          arising out of Seller's breach of its warranties or any of its
          obligations under this Agreement.

     (c)  With respect to Buyer's and Seller's indemnify obligations under this
          Section 9, Seller and Buyer shall be responsible only for direct
          damages and in no event shall either Buyer or Seller be liable for
          indirect, special, consequential or similar damages.

     10.  Force Majeure. Except for Buyer's obligation to pay all monies
hereunder when due, neither party shall be liable for any failure or delay in
performance hereunder which may be

                                        6

<PAGE>

due, in whole or in part, to fire; explosion; adverse weather conditions; labor
difficulties (for whatever cause arising and whether or not the demands of
employees are reasonable or within the party's power to grant); war,
insurrection, riot, act of God or the public enemy; acts of terrorism; law, act,
order, proclamation, decree, regulation, ordinance, instruction or request of
government or other public authorities; order, judgment or decree of any court;
delay or failure of carriers or contractors; labor shortage or inability to
obtain transportation equipment, raw materials, Products, fuel, power, plant
equipment or materials required for maintenance or repairs; or any contingency
or delay or failure or cause of any nature beyond the reasonable control of the
party, whether or not the kind hereinabove specified and whether or not any such
contingency is presently occurring or occurs in the future (a "Force Majeure
Event"). Seller shall exercise its commercially reasonable efforts to remedy
such Force Majeure Event as soon as reasonably possible, but in no event shall
it be required to take any action which would result in materially increasing
its cost of performance hereunder beyond the costs which it would have incurred
hereunder in the absence of such Force Majeure Event. In the event that
deliveries are impeded or supplies curtailed during to any such cause or causes,
Seller shall have the right to apportion deliveries among its then existing
customers on such basis as is equitable without liability for any failure to
perform this Agreement which may result therefrom. Where a party claims an
excuse for nonperformance under this Section, it must give prompt telephonic
notice promptly confirmed by written notice of the occurrence and estimated
duration of the Force Majeure Event to the other party; and shall give prompt
written notice when the Force Majeure Event has been remedied and performance
can recommence hereunder.

     11.  Waiver. Waiver by either party of the performance of any term or
condition of this Agreement by the other party shall not be construed to
constitute a waiver of any other term or condition nor shall such waiver be held
to be a waiver of any right to enforce such term or condition at any subsequent
time during the term of this Agreement.

     12.  Tax Responsibility. Buyer shall promptly pay and discharge any and all
sales, use, excise, transportation and other similar taxes which may be imposed
by federal, state or local authorities upon the sale, use or transportation of
the Product delivered hereunder. In the event that Seller is required to make
payment of any such tax or any penalty for delay in the payment thereof, Buyer
shall reimburse Seller for such payment within one (1) month after the same is
made.

     13.  Assignment. Either Buyer or Seller may assign all of its rights under
this Agreement to a buyer of all or substantially all of its assets with the
prior written consent of the other party, which consent will not be unreasonably
withheld or delayed. Otherwise, none of the parties hereto shall assign its
rights or delegate its duties under this Agreement without the prior written
consent of the other parties hereto except to an Affiliate of such party and
except that AAA or the Companies may assign and/or charge all or any of its
rights under this Agreement by way of security to any bank(s) and/or holders of
any debt securities and/or financial institution(s) and/or hedge counterparties
and/or any other person (together, the "Financiers") lending money or making
other banking facilities available to the Companies, AAA and their respective
affiliates or to any Financiers who provide funds on or in connection with any
subsequent refinancing of any such funding or to any person from time to time
appointed by any Financier to act as a security trustee on behalf of such
Financier; without limitation to the foregoing, any such

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<PAGE>

person or Financier may assign such rights on any enforcement of the security
under such finance arrangement; provided further, however, that no assignment
under this Section 13 shall relieve AAA of its obligations hereunder. Subject to
the foregoing, this Agreement shall be binding on, and inure to the benefit of,
the parties and their respective affiliates, successors and assigns.

     14.  Termination. This Agreement may be terminated before the end of its
term under the following circumstances:

     (a)  The parties may agree to terminate this Agreement at any time and
          under any circumstances that have been mutually agreed upon in
          writing.

     (b)  If one of the parties breaches any material term of this Agreement,
          the other party may give the breaching party a notice in writing which
          specifically sets out the nature and extent of the breach, and the
          steps that must be taken to cure the breach. After receiving such a
          written notice, the breaching party will then have thirty (30) days
          (or such greater period of time as is reasonably necessary under the
          circumstances) to cure the breach. If the breaching party does not do
          so, the non-breaching party will have the right to terminate this
          Agreement.

     (c)  If one of the parties shall become insolvent or shall take advantage
          of any law for the benefit of debtors or makes an assignment of assets
          for the benefit of its creditors or a receiver shall be appointed for
          it or any of its property.

     (d)  In the event that a party to this Agreement incurs costs, expenses,
          and attorneys' fees in connection with protecting its rights or
          enforcing its remedies following a breach of this Agreement by the
          other party, the breaching party must reimburse the non-breaching
          party for all such costs, expenses, and attorneys' fees, regardless of
          whether or not the protection of rights or the enforcement of remedies
          involved judicial proceedings, arbitration proceedings, or other
          formal dispute resolution proceedings. The breaching party must
          reimburse the non-breaching party for these costs, expenses, and
          attorneys' fees within 10 days of receiving a reasonably detailed
          reimbursement claim from the non-breaching party.

     15.  Buyer's Fertilizer Locations. In the event Buyer decides to sell any
assets relating to or comprising its fertilizer locations set forth on Exhibit
"C" attached hereto, Buyer shall provide Seller with notice of such intended
sale and the first opportunity to negotiate the purchase of such assets from
Buyer at prices and on terms and conditions as may be mutually acceptable to the
parties.

     16.  Notices. All notices provided for hereunder shall be given in writing
and personally delivered or sent by United States Registered or Certified Mail
or by facsimile to the addresses below, and shall be deemed effective for all
purposes hereof on the date of delivery in the case of personal service or
facsimile or on the second (2/nd/) business day following postmark, except that
a notice of change of address must actually be received to be effective:

                                        8

<PAGE>

               Seller:           ConAgra International Fertilizer Company
                                 Five Skidaway Village Walk South
                                 Savannah, GA 31411-2905
                                 Attn: Mr. Brian Harlander
                                 Fax:  (912) 598-8692

               With a copy to:   ConAgra Foods, Inc.
                                 One ConAgra Drive
                                 Omaha, NE 68102
                                 Attn: Vice President/Controller
                                 Fax:  (402) 595-4611

               Buyer:            United Agri Products, Inc.
                                 7251 West 4/th/ Street
                                 Greeley, CO 80634
                                 Attn: Mr. Kenny Cordell
                                 Fax:  (970) 347-1560

               With a copy to:   United Agri Products, Inc.
                                 7251 West 4/th/ Street
                                 Greeley, CO 80634
                                 Attn: Legal Department
                                 Fax:  (970) 347-1561

     17.  Incorporation. This Agreement incorporates all the understandings of
the parties in regard to the subject matter hereof and supersedes all prior
negotiations or communications, however given, regarding the subject matter
hereof.

     18.  Amendment. This Agreement may be amended or modified only by a writing
which specifically refers to this Agreement, expressly recites that it
constitutes an amendment to this Agreement, and is subscribed by both parties
hereto. No terms of any purchase order, order confirmation, or similar
instrument shall be deemed to alter, amend or supplement the terms and
conditions of this Agreement.

     19.  Headings. The section, subsection and paragraph headings in this
Agreement are for convenience only and shall not be considered in the
interpretation or construction of any provision of this Agreement.

     20.  Governing Law. This Agreement, its interpretation, performance and
enforcement, shall be governed by the laws of the State of Delaware.

                  [Remainder of page intentionally left blank]

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<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date and year first above written.


BUYER:                                    SELLER:

UNITED AGRI PRODUCTS, INC.                CONAGRA FOODS, INC.


By:   David Bullock                       By:   /s/ Patrick K. Koley
     ---------------------------------         ---------------------------------
Its:  Authorized Signatory                Its:  Authorized Signatory
     ---------------------------------         ---------------------------------


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<PAGE>

                                   EXHIBIT "A"
                                   -----------

Nitrogen:
     .    Urea
     .    Ammonium Nitrate
     .    32% UAN Solution
     .    30% UAN Solution
     .    28% UAN Solution

Phosphates:
     .    Dap
     .    Map
     .    Triple Super Phosphate
     .    Nitric Phosphate
     .    11-37-0 Solution
     .    10-34-0 Solution
     .    Super Phosphoric Acid

Potash:
     .    Granular MOP
     .    Standard Grade MOP
     .    Soluble MOP
     .    K-Mag

Sulfur:
     .    Ammonium Sulfate
     .    Ammonium Thiosulfate Solution
     .    90% Dry Sulfur

Zinc:
     .    Dry Zinc Sulfate
     .    Liquid Zinc

Boron:
     .    Granular Boron
     .    Liquid Boron

Homogenized Fertilizers:
     .    Various Analysis (Example - dry 16-16-16)

Anhydrous Ammonia

                                       11

<PAGE>

                                   EXHIBIT "B"
                                   -----------

DATE:

TO:

ATTN:

RE:       Supply Agreement Between ConAgra International Fertilizer Company and
          United Agri Products, Inc., dated _____________, 2003

--------------------------------------------------------------------------------

CONFIRMING OUR PHONE CONVERSATION, CONAGRA INTERNATIONAL FERTILIZER COMPANY
("SELLER") HAS SOLD AND UNITED AGRI PRODUCTS, INC. ("BUYER") HAS PURCHASED UNDER
THE FOLLOWING TERMS AND CONDITIONS:

PRODUCT:

QUALITY:

QUANTITY:

SHIPPING PERIOD:         MONTHLY

PRICE:

PACKAGING:

TRANSFER OF TITLE:       TITLE TO PRODUCT SHALL PASS FROM SELLER TO BUYER
                         PROGRESSIVELY UPON LOADING OF PRODUCT INTO BARGE OR
                         TRANSPORTATION VEHICLE

TRANSPORTATION:          SELLER TO ARRANGE BARGE.

                         BUYER HAS UP TO ___ FREE DAYS TO DISCHARGE BARGE AT
                         DESTINATION; DEMURRAGE CHARGES OF USD $_____/DAY APPLY
                         THEREAFTER.

                         BUYER TO EMPTY BARGE ENTIRELY. ANY EXCESS CLEANING
                         CHARGES OVER $_____ THAT ARE ASSESSED TO SELLER DUE TO
                         PRODUCT REMAINING IN THE BARGE WILL BE FOR THE ACCOUNT
                         OF THE BUYER.

                                       12

<PAGE>

PAYMENT TERMS:           NET CASH DUE AFTER BUYER'S RECEIPT OF INVOICE IN
                         ACCORDANCE WITH ___________, 2003 SUPPLY AGREEMENT
                         BETWEEN THE PARTIES.

TERMS:                   THIS SALE AND ANY SUBSEQUENT CONTRACT IS SUBJECT TO
                         DEFINITIONS AS CONTAINED IN INCOTERMS 2000 EDITION.

OUR HARD COPY CONFIRMATION IS TO FOLLOW. WE APPRECIATE THE OPPORTUNITY TO HAVE
CONCLUDED THIS BUSINESS WITH YOU.

BEST REGARDS,

CONAGRA INTERNATIONAL                     UNITED AGRI PRODUCTS, INC.
FERTILIZER COMPANY                        (BUYER)
(SELLER)


By:                                       By:
     ---------------------------------         ---------------------------------
Its:                                      Its:
     ---------------------------------         ---------------------------------

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<PAGE>

                                   EXHIBIT "C"
                                   -----------

..    Grand Forks, ND
..    Devils Lake, ND
..    Pasco, WA
..    Moses Lake, WA


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