This article describes a method for controlled surface coating of cellulose fibers with micro-size hydrogel particles. The addition of ethyleneglycol dimethacrylate (EDMA) to the diethylene glycol methacrylate (DEGMA) monomer mixture used for grafting resulted in a dramatic enhancement of the grafting amount onto ozone-activated fibers and subsequent formation of particles on the fiber surfaces, as observed with AFM and SEM. The enhancement of the amount of grafting was explained by an initiation of the pendent double bonds and autoacceleration of graft polymerization as indicated by differential scanning calorimetry (DSC). Such 3-dimensional growth had a maximum at 4% of crosslinker and was significantly reduced when longer crosslinkers were used. This was explained by a cyclization reaction of the pendant double bonds. The surface structures were controlled by selecting the graft polymerization time.