PURPOSE: To easily, accurately carry out a specified sowing operation by using a holder 1 for plants to be raised having a specific structure.

CONSTITUTION: A supporting panel 2 for a holder 1 for plants to be raised set up on a setting panel 8 are provided with notches 2a along which a double- sided tape 5 is fitted. And, a porous water-retaining member is provided so as to cover the notches 2a from below and folds 3 are provided so as to bend upward the side of the notches 2a. Seeds 6 are sowed on the double-sided tape 5, and the panel 2 is formed with the fold lines 3 and finished into the setting panel, thus carrying out the objective sowing.