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                                                                    EXHIBIT 10.1

                               AMENDING AGREEMENT
                              --------------------


         THIS AGREEMENT made effective as of the 23rd day of June, 1999,

BETWEEN:

         AGRIUM INC., a corporation with an office in the City of Calgary in the
         Province of Alberta (formerly known as Cominco Fertilizers Ltd.)

                         (hereinafter called "Agrium")

                                     -and-

         PLANET POLYMER TECHNOLOGIES, INC., a corporation with an office in the
         City of San Diego, State of California, United States of America

                         (hereinafter called "Planet")


         WHEREAS a Technology Development and License Agreement was entered into
between Agrium and Planet dated as of January 30, 1995 (the "Agreement");

         AND WHEREAS the parties consider it appropriate to amend the Agreement
by changing certain provisions of the Agreement;

         NOW THEREFORE in consideration of the foregoing and the mutual
covenants and promises herein contained and for other good and valuable
consideration, the receipt and sufficiency of which is hereby acknowledged by
the parties hereto, the parties hereto agree as follows:

         1.    Paragraph 8.1 of the Agreement shall be amended so as to read as
               follows:

               During the term of this Agreement Planet shall not conduct any
               development work of the same nature or type as the Work, for any
               third party, except for Agway Consumer Products, Inc. or Agway
               Inc. ("Agway"), on any subject if the intended use falls within,
               or could reasonably be expected to fall within, Agrium's Field of
               Business formerly Cominco's Field of Business, as defined herein.

               If Planet enters into any arrangements or agreements with Agway
               for a license under any of the Planet Technology, the New
               Technology or with respect to new compositions of matter, new
               chemical complexes, improved chemical complexes, association
               compounds, blends, mixtures or compositions of coating materials,
               polymer materials or new products or new processes relating
               thereto ("Other New Technology") and which could reasonably be
               expected to fall within Agrium's Field of Business or any
               agreements or arrangements with Agway for the right to

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                                      -2-

               produce, market or distribute Fertilizer Products, which term,
               for purposes of this paragraph 8, shall be as defined in
               paragraph 1.1 (but deleting reference to "produced, distributed
               or marketed by Cominco from time to time"), or Biological
               Products, which term, for purposes of this paragraph 8, shall be
               as defined in paragraph 1.2 (but deleting reference to "produced,
               distributed or marketed by Cominco from time to time"); under or
               with respect to the Planet Technology, the New Technology or the
               Other New Technology (the said Fertilizer Products and Biological
               Products being collectively called the "New Products") and if

                    (i)       the intended place of use is within the Territory
                              and

                    (ii)      the intended use falls within, or could reasonably
                              be expected to fall within Agrium's Field of
                              Business, or

                    (iii)     if pursuant to such agreements or arrangements,
                              the intended use falls within, or could reasonably
                              be expected as falling within Agrium's Field of
                              Business,

               Planet shall provide Agrium with an option, to be exercised by
               Agrium within ninety (90) days from receipt of written notice, to
               acquire a license and the right to produce, market and distribute
               the New Products, on substantially the same terms and conditions
               as those contained in this Agreement, including but not limited
               to those terms and conditions set out in paragraphs 6.1, 6.2 and
               6.3.

               Subject to the foregoing exception, during the term of this
               Agreement, Planet shall not enter into any arrangement or
               agreements with any third party for a license under any of the
               Planet Technology, the New Technology or the Other New Technology
               if the intended place of use is within the Territory and the
               intended use falls within, or could reasonably be expected to
               fall within, Agrium's Field of Business, without first offering
               such arrangement to Agrium and at terms no less favorable to
               Agrium than those offered to a third party.

         2.    All other provisions of the Agreement not amended by this
               Amending Agreement shall be unchanged and remain in full force
               and effect.

               IN WITNESS WHEREOF the parties hereto have executed this Amending
Agreement as of the date first above written.


         Agrium Inc.


         Per: /s/ Dennis Kalma
              ----------------------------


         Planet Polymer Technologies, Inc.


         Per: /s/ Robert J. Petcavich
              ----------------------------