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Exhibit 10.23

AGREEMENT OF PURCHASE AND SALE OF PARTNERSHIP INTEREST

        This AGREEMENT OF PURCHASE AND SALE OF PARTNERSHIP INTEREST (this
"Agreement") is made and entered into as of this 5th day of December, 2002 by
and between USAA REAL ESTATE COMPANY, a Texas corporation having an office at
9830 Colonnade Boulevard, Suite 600, San Antonio, Texas 78230 (hereinafter
referred to as the "Seller") and GRIFFIN LAND & NURSERIES, INC., a Delaware
corporation having an office at 204 West Newberry Road, Bloomfield, Connecticut
06002 (hereinafter referred to as the "Purchaser").

R E C I T A L S:

        WHEREAS, the Seller and Purchaser are the sole Partners in USGC Joint
Venture (the "Joint Venture"), a Connecticut general partnership, pursuant to
the terms of that certain USGC Joint Venture Agreement (the "Joint Venture
Agreement") dated as of June 13, 1984 by and between Seller and Purchaser; and

        WHEREAS, Seller owns and holds an undivided 70% interest in the Joint
Venture ("Seller's Partnership Interest"), and Purchaser owns and holds an
undivided 30% interest in the Joint Venture ("Purchaser's Partnership
Interest"); and

        WHEREAS, the Joint Venture owns certain improved real property commonly
known as 5 & 7 Waterside Crossing, located in Windsor, Connecticut, along with
certain related personal and intangible property (collectively, the "Property");
and

        WHEREAS, the Seller has agreed to sell and assign, and Purchaser has
agreed to purchase and take an assignment of, Seller's Partnership Interest; and

        WHEREAS, Seller and Purchaser have agreed to such sale and assignment on
the terms and conditions contained herein.

        NOW, THEREFORE, in consideration of the foregoing, of the covenants,
promises and undertakings set forth herein, and for good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged,
Seller and Purchaser agree as follows:

        Section 1.    Sale and Assignment of Seller's Percentage.    For the
consideration specified in Section 2, the Seller hereby agrees to sell,
transfer, convey, and assign to the Purchaser all of Seller's Partnership
Interest and all of Seller's rights under the Joint Venture Agreement,
including, without limitation, (i) all rights of the Seller to receive Profits,
Losses and other property or assets due and to become due to the Seller under or
pursuant to the Joint Venture Agreement, and (ii) all rights of the Seller to
receive proceeds or benefit of any indemnity, warranty, or other payments with
respect to the Joint Venture (and all of the foregoing, together with Seller's
Partnership Interest, are hereinafter collectively referred to as "Seller's
Percentage"). The Purchaser hereby agrees to purchase and take an assignment of
Seller's Percentage.

        Section 2.    Purchase Price.    The purchase price for Seller's
Percentage (the "Purchase Price") is EIGHT MILLION SIX HUNDRED FIFTY THOUSAND
AND NO/100 DOLLARS ($8,650,000.00).

        Section 3.    Payment.    Payment of the Purchase Price is to be made in
cash as follows:

(a)Prior to the date hereof Purchaser has made an earnest money deposit of ONE
MILLION AND NO/100 DOLLARS ($1,000,000.00) (the "Deposit"). The Deposit has been
placed with and is being held in escrow by Commonwealth Land Title Insurance
Company (the "Title Company"), located at 111 Founders Plaza, Suite 1702, East
Hartford, Connecticut 06108, Attention: George Browne, Esq., in an interest
bearing account at Fleet National Bank. Any interest earned by the Deposit shall
be considered as part of the Deposit. Except as otherwise expressly provided in
this Agreement, the Deposit shall be applied to the Purchase Price at Closing.

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(c)At Closing, Purchaser shall pay to (or cause to be paid to) Seller EIGHT
MILLION SIX HUNDRED FIFTY THOUSAND AND NO/DOLLARS ($8,650,000.00), inclusive of
the Deposit and subject to adjustment for the prorations as provided herein.

        Section 4.    Closing.    Payment of the Purchase Price and the closing
hereunder (the "Closing") will take place at the offices of the Title Company or
at such other place as may be agreed upon in writing by Seller and Purchaser.
Both parties hereby agree that the Closing shall take place no later than
December 6, 2002. Purchaser may, at its option and upon at least five
(5) business days prior written notice to Seller, elect to accelerate the
Closing date (and the actual Closing date hereunder is hereinafter referred to
as the "Closing Date"). Although specifically not a condition to Purchaser's
obligations hereunder, Seller acknowledges that Purchaser may wish to finance
its acquisition of Seller's Percentage by mortgaging the Property. Seller
agrees, without additional cost to Seller and without deferring the Closing
Date, to cooperate with Purchaser in all reasonable ways in order to effectuate
such financing, including, without limitation, closing in escrow with the Title
Company in order to permit the simultaneous conveyance and mortgaging of the
Property.

        Section 5.    Seller's Continuing Rights and Obligations.    From and
after the Closing Date, Seller shall cease to be a partner in the Joint Venture,
and shall cease to be entitled to or liable for any rights, proceeds, interests,
powers, warranties, obligations and/or liabilities in the Joint Venture, under
the Joint Venture Agreement and/or relating to the Property with respect to any
period from and after the Closing Date. With respect to all entitlements and
liabilities of the Joint Venture arising prior to the Closing Date, except as
set forth in Section 11 hereof Seller shall remain entitled to (and liable for)
70% of all such rights and obligations, and Purchaser shall be entitled to (and
liable for) 30% of all such rights and obligations. Consistent with the
foregoing, Purchaser hereby agrees to indemnify Seller against and hold Seller
harmless from any and all cost, liability, loss, damage or expense, including,
without limitation, reasonable attorneys' fees, arising out of the Joint Venture
Agreement and/or the Property and attributable to any event or circumstance
first occurring or arising from and after the Closing Date. Further consistent
with the foregoing, Purchaser (with respect to 30%) and Seller (with respect to
70%) hereby each agree to indemnify the other against and hold the other
harmless from any and all cost, liability, loss, damage or expense, including,
without limitation, reasonable attorneys' fees, arising out of the Joint Venture
Agreement and/or the Property and attributable to any event or circumstance
occurring or arising prior to the Closing Date.

        Section 6.    Dissolution or Continuation of Joint Venture.    After the
Closing Date, Purchaser shall hold Seller's Percentage plus Purchaser's
Partnership Interest in the Joint Venture, for a combined 100% of the ownership
interests in the Joint Venture, resulting in dissolution of the Joint Venture
pursuant to Section 8.1 of the Joint Venture Agreement. Notwithstanding said
Section 8.1, as an alternative to dissolution it is agreed that Purchaser may at
its option assign this Agreement to a subsidiary entity in accordance with
Section 17(d) hereof, in which event Purchaser may elect to continue the Joint
Venture after the Closing Date.

        Section 7.    Inspections and Approvals.    The parties acknowledge that
this Agreement contains no provision for an inspection or a due diligence
period. Seller and Purchaser agree that Purchaser, in acquiring Seller's
Percentage hereunder, is accepting the Property in an "as-is" condition.

        Section 8.    Prior to Closing.    Until Closing, the Joint Venture
shall:

        (a)    Insurance.    Maintain all existing insurance on the Property,
including, without limitation, insurance against fire and other hazards covered
by extended coverage endorsement and comprehensive public liability insurance
against claims for bodily injury, death and property damage occurring in, on or
about the Property.

        (b)    Operation.    Operate and maintain the Property in a businesslike
manner and in accordance with the Joint Venture's past practices with respect to
the Property, and make any and

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all repairs and replacements reasonably required to deliver the Property to
Purchaser at Closing in its present condition, normal wear and tear excepted,
provided that in the event of any loss or damage to the Property as described in
Section 11, Section 11 shall be controlling.

        (c)    Compliance with Agreements.    Comply with the terms, covenants,
conditions and obligations contained in all the leases, contracts and any other
material document or agreement affecting the Property and to monitor compliance
thereunder, consistent with past practices.

        (d)    New Contracts.    Not enter any new third-party contracts or
leases unless Purchaser consents thereto in writing.

        (e)    Other Agreements.    Not enter into, modify, amend or terminate
any existing lease, contract or other agreement with respect to the Property
which would encumber or be binding upon the Property or the Joint Venture from
and after the Closing Date, without in each instance obtaining the prior written
consent of Purchaser.

        (f)    Take no action to change the status of title to the Property.

        Section 9.    Representations and Warranties.    

        (a)    By Seller.    To induce Purchaser to enter in this Agreement,
Seller represents and warrants to Purchaser as follows:

(i)The Seller has (and will, through the Closing Date) duly, truly and fully
performed and observed the material undertakings, agreements, warranties,
obligations and conditions on the part of the Seller that are contained in the
Joint Venture Agreement, and the Seller is not in any respect in material
default under or as to any of such undertakings, agreements, warranties,
obligations and conditions. The Seller's execution, delivery and performance of
this Agreement has been authorized by all necessary action on the Seller's part
and does not require any consent, authorization or approval of any governmental
entity or other third party.

(ii)This Agreement is the valid and binding obligation of the Seller,
enforceable in accordance with its terms;

(iii)The Seller is the sole owner of Seller's Percentage, and the Seller has
good title to the Seller's Percentage, free and clear of any liens, claims,
encumbrances, security interests, options or other claims of any nature;

(iv)The Seller will cause the Joint Venture to comply with the provisions of
Section 8 hereof; and

(v)To Seller's knowledge, no investigation, action or proceeding is pending and,
to Seller's knowledge, no action or proceeding is threatened and no
investigation looking toward such an action or proceeding has begun which
(A) questions the validity of this Agreement or any action to be taken pursuant
hereto, (B) will result in any material adverse change in the business
operation, affairs or condition of the Joint Venture, or (C) results in or
subjects the Joint Venture to a material liability. As used in this Section 9
and elsewhere in this Agreement, the phrase "to Seller's knowledge" or phrases
of similar import mean and are limited to the actual current knowledge of
Seller, without any independent investigation or inquiry having been made, and
not to any constructive knowledge of Seller.

        (b)    By Purchaser.    To induce Seller to enter in this Agreement,
Purchaser represents and warrants to Seller as follows:

(i)The Purchaser has (and will, through the Closing Date) duly, truly and fully
performed and observed the material undertakings, agreements, warranties,
obligations and conditions on the part of the Purchaser that are contained in
the Joint Venture Agreement, and the Purchaser is not in any respect in material
default under or as to any of such undertakings, agreements,

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warranties, obligations and conditions. The Purchaser's execution, delivery and
performance of this Agreement has been authorized by all necessary action on the
Purchaser's part and does not require any consent, authorization or approval of
any governmental entity or other third party.

(ii)This Agreement is the valid and binding obligation of the Purchaser,
enforceable in accordance with its terms;

(iii)The Purchaser will cause the Joint Venture to comply with the provisions of
Section 8 hereof; and

(iv)To Purchaser's knowledge, no investigation, action or proceeding is pending
and, to Purchaser's knowledge, no action or proceeding is threatened and no
investigation looking toward such an action or proceeding has begun which
(A) questions the validity of this Agreement or any action to be taken pursuant
hereto, (B) will result in any material adverse change in the business
operation, affairs or condition of the Joint Venture, or (C) results in or
subjects the Joint Venture to a material liability. As used in this Section 9
and elsewhere in this Agreement, the phrase "to Purchaser's knowledge" or
phrases of similar import mean and are limited to the actual current knowledge
of Purchaser, without any independent investigation or inquiry having been made,
and not to any constructive knowledge of Purchaser.

        (c)    By Both Parties.    Both parties acknowledge that there are no
brokerage firms involved in this transaction other than CB Richard Ellis (CBRE).
Seller alone, and not the Joint Venture, shall be responsible for the payment of
the commission to CBRE in accordance with separate agreement between CBRE and
Seller, and Seller shall indemnify Purchaser against any claim for a commission
by CBRE arising as a result of this Agreement. Each party (the "indemnifying
party") shall indemnify the other for the claim of any other broker or other
party claiming a fee or commission arising out of this Agreement as a result of
the acts of the indemnifying party.

        (d)    Survival of Representations and Warranties.    Reference is made
to Seller's representations and warranties as set forth in Subsections
9(a)(ii) and (iii), and to Purchaser's representation and warranty as set forth
in Subsection 9(b)(ii) (collectively, the "Continuing Reps"). Other than the
Continuing Reps, which shall not be limited in duration, each of the other
representations and warranties of Seller and Purchaser contained in this
Agreement will survive for a period of eighteen (18) months after the Closing.
Other than the Continuing Reps, any claim that Seller or Purchaser may have at
any time against the other for a breach of any other representation or warranty
contained in this Agreement, whether known or unknown, which is not specifically
asserted by written notice from Seller or Purchaser to the other before the
expiration of such eighteen (18) month period will not be valid or effective,
and the offending party will have no liability with respect thereto.

        Section 10.    Costs and Prorations.    

        A.    Real Estate.    At Closing, all real estate taxes, rents,
utilities, and all other items of income and expense normally adjusted in real
estate transactions and applicable to the Property shall be adjusted between
Purchaser and the Joint Venture as of the Closing Date, with the intent that
Purchaser shall bear all expenses and receive all income with respect to the
Property accruing from and after the Closing Date, and the Joint Venture shall
bear all expenses and receive all income with respect to the Property accruing
through midnight at the end of the day preceding the Closing Date. However,
delinquent rents will not be prorated at Closing. Rents are delinquent if they
were due prior to the Closing Date but payment thereof has not been made on or
before the Closing Date. Purchaser shall use commercially reasonable efforts
during the three (3) month period immediately following the Closing Date to
collect and promptly remit to Seller rents or other amounts due Seller for the
period prior to the Closing Date. All rents collected after the Closing Date
shall be applied first to rents due

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for the month in which the Closing occurs, second to rents for periods after the
month in which the Closing Date occurs (provided that rents which are received
prior to the due date, unless specified by the tenant as advance payments, shall
be applied to unpaid periods prior to the Closing Date), and third to rents for
periods prior to the month in which the Closing Date occurs. Purchaser's
obligations with respect to the collection and remittance of rents to Seller
shall survive Closing.

        B.    Joint Venture.    Upon completing the Property prorations set
forth in Section 10(A) above, Seller and Purchaser shall further apportion the
income and expenses applicable to the Joint Venture 70% to Seller and 30% to
Purchaser. All other items of income and expense applicable to the Joint Venture
up to the Closing Date shall likewise be allocated 70% to Seller and 30% to
Purchaser. In addition, all costs and expenses incurred by either Seller or
Purchaser in negotiating and closing the transaction contemplated by this
Agreement (including without limitation attorneys' fees) shall be allocated 70%
to Seller and 30% to Purchaser. Notwithstanding the foregoing, controlling
interest transfer taxes payable under Connecticut law upon the transfer of
Seller's Percentage in excess of $96,015.00 shall be 100% Seller's
responsibility. In addition, at Closing, provided that the Joint Venture or
Seller is not otherwise charged for the cost of a title insurance policy at
Closing, Purchaser shall be entitled to a credit of $7,741.00 (70% of the cost,
net of any commission, of an owner's title insurance policy in the amount of
$12,360,000.00). Except as otherwise expressly provided herein, the purpose and
intent of the prorations and apportionments set forth in this Section 10 and
elsewhere in this Agreement are that the Joint Venture shall bear all expenses
of ownership and operation of the Property and shall receive all income
therefrom accruing through midnight at the end of the day preceding the Closing
Date, with Seller bearing 70% of all of such expenses and receiving 70% of all
of such income, and Purchaser bearing 30% of all of such expenses and receiving
30% of all of such income.

        C.    Net Adjustment.    Upon completing the adjustments set forth
above, the net credit (or debit) which would otherwise be payable to (or payable
from) Purchaser shall be reflected as a credit (or debit) against the Purchaser
Price, as the case may be. In this connection, it is understood that, although
final adjustment will be made between Purchaser and Seller wherever possible,
certain items of income and/or expense may not be available for adjustment
and/or may only be estimated at Closing. In all such instances, final adjustment
shall be made as soon as possible and in any event within one hundred twenty
(120) days following the Closing, and Seller and Purchaser agree to cooperate
with each other, reasonably and in good faith, as shall be necessary to finalize
any post-closing adjustment.

        Section 11.    Damage, Destruction or Condemnation.    If, prior to
Closing, all or any portion of the Property is rendered untenantable or is
destroyed or damaged, or is taken under power of eminent domain, Purchaser shall
close this transaction on the date and at the Purchase Price agreed upon in
Section 2 without any diminution whatsoever, and Seller shall assign to
Purchaser 100% of the proceeds of any insurance policies payable to Seller on
account of, in connection with or as a result of such damage or destruction,
and/or 100% of any condemnation award.

        Section 12.    Closing Conditions.    

        (a)    Purchaser's Closing Conditions.    The obligation of Purchaser to
acquire Seller's Percentage from Seller shall be subject to the satisfaction of
the following conditions precedent on and as of the Closing Date:

        (i)    Seller shall have delivered to Purchaser Seller's Closing
Documents (as hereinafter defined).

        (ii)  All representations and warranties of Seller herein shall continue
to be true, correct and complete in all material respects on and as of the
Closing Date, and Seller shall have performed all covenants and obligations
required to be performed by Seller hereunder on or before the Closing Date.

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        (b)    Seller's Closing Conditions.    The obligation of Seller to
convey the Seller's Percentage to Purchaser shall be subject to the satisfaction
of the following conditions precedent on and as of the Closing Date:

        (i)    Purchaser shall have delivered to the Title Company the Purchase
Price payable hereunder.

        (ii)  Purchaser shall have delivered to Seller Purchaser's Closing
Documents (as hereinafter defined).

        (iii)  All representations and warranties of Purchaser herein shall be
true, correct and complete in all material respects on and as of the Closing
Date and Purchaser shall have performed all covenants and obligations required
to be performed by Purchaser on or before the Closing Date.

        Section 13.    Closing and Escrow.    

(a)Escrow instructions.    Upon execution of this Agreement, the parties shall
deliver an executed counterpart of this Agreement to the Title Company to serve
as the instructions to the Title Company as the escrow holder for consummation
of the transaction contemplated herein. Seller and Purchaser agree to execute
such additional and supplementary escrow instructions as may be appropriate to
enable the Title Company to comply with the terms of this Agreement; provided,
however, that in the event of any conflict between the provisions of this
Agreement and any supplementary escrow instructions, the terms of the Agreement
shall prevail.

(b)Seller's Deliveries.    Seller shall deliver either at Closing the following
original documents (collectively, "Seller's Closing Documents"), each executed
and, if required, acknowledged:

(i)An Assignment of Partnership Interest (the "Assignment") in the form attached
hereto as Exhibit A;

(ii)Documentation to establish the reasonable satisfaction of Purchaser and the
Title Company the due authorization of the sale of Seller's Percentage by Seller
and the delivery of the Assignment;

(iii)On behalf of the Joint Venture, a parties in possession affidavit, a
mechanic's lien affidavit, and such other documents, certificates, and other
instruments as the Title Company may reasonably require and as are customary in
like transactions in the State of Connecticut.
(c)Purchaser's Deliveries.    At the Closing, Purchaser shall (i) pay Seller the
Purchase Price; (ii) execute any applicable agreements required under this
Agreement (collectively, the "Purchaser's Closing Documents"); (iii) provide
documentation to establish to the reasonable satisfaction of Seller and the
Title Company the due authorization of the purchase of Seller's Percentage by
Purchaser and the delivery of the Assignment; and (iv) on behalf of the Joint
Venture, execute a parties in possession affidavit, a mechanic's lien affidavit,
and such other documents, certificates, and other instruments as the Title
Company may reasonably require and as are customary in like transactions in the
State of Connecticut.

        Section 14.    Default; (Failure of Condition).    

        (a)  Purchaser Default.    IF PURCHASER SHALL BECOME IN BREACH OF OR
DEFAULT UNDER THIS AGREEMENT BEYOND THE EXPIRATION OF THE APPLICABLE CURE
PERIOD, IF ANY, OR THE CLOSING DATE AND THE CLOSING DOES NOT OCCUR AS A RESULT
THEREOF (OTHER THAN BY REASON OF A BREACH OR DEFAULT BY SELLER UNDER THIS
AGREEMENT BEYOND THE EXPIRATION OF THE APPLICABLE CURE PERIOD, IF ANY, OR THE
CLOSING DATE, THE DEPOSIT SHALL BE RETAINED BY SELLER AS LIQUIDATED

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DAMAGES, AND BOTH PARTIES SHALL BE RELIEVED OF AND RELEASED FROM ANY FURTHER
LIABILITY HEREUNDER. SELLER AND PURCHASER AGREE THAT THE DEPOSIT IS A FAIR AND
REASONABLE AMOUNT TO BE RETAINED BY SELLER AS AGREED AND LIQUIDATED DAMAGES IN
LIGHT OF SELLER'S REMOVAL OF THE PROPERTY FROM THE MARKET AND THE COSTS INCURRED
BY SELLER AND SHALL NOT CONSTITUTE A PENALTY OR A FORFEITURE.

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Purchaser's Initials  

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Seller's Initials

        (b)    Seller Default.    If Seller shall refuse or fail to convey
Seller's Percentage as herein provided for any reason other than (i) a default
by Purchaser beyond the expiration of the applicable cure period, if any, or the
Closing Date, or (ii) any other provision of this Agreement which permits Seller
to terminate this Agreement or otherwise relieves Seller of the obligation to
convey Seller's Percentage, Purchaser may, as its sole remedy, either
(x) terminate this Agreement and receive a refund of the Deposit or (y) pursue a
suit for specific performance; provided, however, if Purchaser is unsuccessful
in its suit for specific performance but Seller is adjudicated in default of its
obligations hereunder, it shall nevertheless be entitled to the remedies
provided in clause (ii)(x) above.

        Section 15.    Amendment, Modification and Waiver.    No amendment,
supplement, modification, waiver or termination of this Agreement or any
provisions hereof shall be binding unless executed in writing by all parties
hereto. No waiver of any of the provisions of this Agreement shall constitute a
waiver of any other provision (whether or not similar), nor shall such waiver
constitute a continuing waiver unless otherwise expressly provided.

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        Section 16.    Notices.    Any notice required or permitted to be given
hereunder shall be deemed to be given when hand delivered, transmitted by
facsimile (with electronic confirmation of receipt) or one (1) business day
after pickup by Emery Air Freight, Airborne, Federal Express, or similar
overnight express service, in either case addressed to the parties at their
respective addresses referenced below:

If to Seller:   USAA Real Estate Company
9830 Colonnade Boulevard, Suite 600
San Antonio, Texas 78230
Attention: Elizabeth Hamilton/Susan Swank
Telephone: (210) 498-2994
Fax: (210) 691-3324
with copies to:
 
USAA Real Estate Company
9830 Colonnade Boulevard, Suite 600
San Antonio, Texas 78230
Attention: Susan Wallace
Telephone: (210) 498-3222
Fax: (210) 691-3259
If to Purchaser:
 
Griffin Land & Nurseries, Inc.
204 West Newberry Road
Bloomfield, CT 06002
Attention: Thomas M. Lescalleet
Telephone: (860) 286-7600
Fax: (860) 286-7653
with copies to:
 
Murtha Cullina LLP
CityPlace I, 185 Asylum Street
Hartford, Connecticut 06103-3469
Attention: Thomas M. Daniells
Telephone: (860) 240-6078
Fax: (860) 240-6150

or in each case to such other address as either party may from time to time
designate by giving notice in writing to the other party. Telephone numbers are
for informational purposes only. Effective notice will be deemed given only as
provided above.

        Section 17.    Miscellaneous.    

        (a)    Entire Agreement.    This Agreement, together with the Exhibits
attached hereto, all of which are incorporated by reference, is the entire
agreement between the parties with respect to the subject matter hereof, and no
alteration, modification or interpretation hereof shall be binding unless in
writing and signed by both parties.

        (b)    Severability.    If any provision of this Agreement or
application to any party or circumstances shall be determined by any court of
competent jurisdiction to be invalid and unenforceable to any extent, the
remainder of this Agreement or the application of such provision to such person
or circumstances, other than those as to which it is so determined invalid or
unenforceable, shall not be affected thereby, and each provision hereof shall be
valid and shall be enforced to the fullest extent permitted by law.

        (c)    Applicable Law.    This Agreement shall be construed and enforced
in accordance with the laws of the State of Connecticut.

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        (d)    Assignability.    Neither party may assign this Agreement without
first obtaining the other party's written consent, except that Purchaser may
assign this Agreement to any entity wholly owned, directly or indirectly, by
Purchaser. Any assignment in contravention of this provision shall be void. No
assignment shall release Purchaser herein named from any obligation or liability
under this Agreement. Any assignee shall be deemed to have made any and all
representations and warranties made by Purchaser hereunder, as if the assignee
were the original signatory hereto.

        (e)    Successors Bound; Survival.    This Agreement shall be binding
upon and inure to the benefit of Purchaser and Seller and their respective
successors and permitted assigns. The provisions of this Agreement shall survive
the Closing.

        (f)    Waivers, Etc.    Any waiver of any term or condition of this
Agreement, or of the breach of any covenant, representation or warranty
contained herein, in any one instance, shall not operate as or be deemed to be
or construed as a further or continuing waiver of any other breach of such term,
condition, covenant, representation or warranty or any other term, condition,
covenant, representation or warranty, nor shall any failure at any time or times
to enforce or require performance of any provision hereof operate as a waiver of
or affect in any manner such party's right at a later time to enforce or require
performance of such provision or any other provision hereof. This Agreement may
not be amended, nor shall any waiver, change, modification, consent or discharge
be effected, except by an instrument in writing executed by or on behalf of the
party against whom enforcement of any amendment, waiver, change, modification,
consent or discharge is sought.

        (g)    Captions.    The captions in this Agreement are inserted only as
a matter of convenience and for reference and in no way define, limit or
describe the scope of this Agreement or the scope or content of any of its
provisions.

        (h)    Attorneys' Fees.    In the event of any litigation arising out of
this Agreement, the prevailing party shall be entitled to reasonable attorneys'
fees and costs.

        (i)    Time of Essence.    Time is of the essence in this Agreement.

        (j)    Counterparts.    This Agreement may be executed and delivered in
any number of counterparts, each of which so executed and delivered shall be
deemed to be an original and all of which shall constitute one and the same
instrument.

        (k)    Recordation.    Purchaser and Seller agree not to record this
Agreement or any memorandum hereof.

        (l)    Proper Execution.    The submission by Seller to Purchaser of
this Agreement in unsigned form shall be deemed to be a submission solely for
Purchaser's consideration and not for acceptance and execution. Such submission
shall have no binding force and effect, shall not constitute an option, and
shall not confer any rights upon Purchaser or impose any obligations upon Seller
irrespective of any reliance thereon, change of position or partial performance.
The submission by Seller of this Agreement for execution by Purchaser and the
actual execution and delivery thereof by Purchaser to Seller shall similarly
have no binding force and effect on Seller unless and until Seller shall have
executed this Agreement and the Deposit shall have been received by the Title
Company and a counterpart of this Agreement shall have been delivered to
Purchaser.

9

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

Signed, Sealed and Delivered
in the Presence of:   SELLER:
USAA REAL ESTATE COMPANY
/s/  ELIZABETH HAMILTON      

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Name: Elizabeth Hamilton
 
By:
/s/  SUSAN WALLACE      

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Name: Susan Wallace
Title: Vice President /s/  TONI M. FISHER      

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Name: Toni M. Fisher     Hereunto Duly Authorized
 
 
PURCHASER:
GRIFFIN LAND & NURSERIES, INC.
/s/  THOMAS M. DANIELLS      

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Name: Thomas M. Daniells
 
By:
/s/  THOMAS M. LESCALLEET      

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Name: Thomas M. Lescalleet
Title: Senior Vice President /s/  EILEEN M. MCCARTHY      

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Name: Eileen M. McCarthy     Hereunto Duly Authorized

        An original, fully executed copy of this Agreement has been received by
the Title Company's agent this 6th day of December, 2002, and by execution
hereof the Title Company's agent hereby covenants and agrees to be bound by the
terms of this Agreement. Receipt of the $1,000,000.00 Deposit is also confirmed.

    COMMONWEALTH LAND TITLE COMPANY
 
 
By:
/s/  PATRICIA A. REJMAN      

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Name: Patricia A. Rejman
Title: Vice President

10

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Exhibit 10.23