Abstract: A method for the acclimatization of plant propagules obtained by tissue culture techniques allows the direct field rooting of the propagules. Tissue culture propagules are first treated under conditions which provide for hardening or lignification of the propagule prior to root induction. The hardened propagules are exposed to a root induction medium for a time sufficient to initiate root formation, but are removed from the medium prior to root emergence. The plantlets are then substantially immediately planted in the field where root formation occurs. Root formation in the field avoids root shock which may occur when plantlets are transplanted after root formation is accomplished under greenhouse conditions. The propagules which are planted in the field are protected by a light and moisture barrier which provides for controlled humidity, light intensity, and temperature conditions until the resulting plantlet is sufficiently acclimatized to survive in the uncontrolled environment.