The clash against the non-league Dragons was due to be played on July 15 but the Shrimpers, who are yet to make a signing this summer, are now keen to send a side down to play an evening game in the autumn instead.
Southend assistant manager Paul Brush told the club's official website: "After due consideration with the current size of the squad we have agreed with Wivenhoe to push back our friendly.
"Some players might now have the option of playing more at Canvey Island next week than the 45 minutes we had planned.
"But we felt on reflection that four games was too much too soon.
"We are very impressed with the attitude and team spirit in pre-season training so far and we will continue our gradual build-up to the start of the season."