The invention relates to methods for fabricating a flowable hemostatic composition. The invention also relates to hemostatic compositions and methods for promoting wound healing. In various embodiments, the hemostatic compositions comprise crosslinkable collagen molecules having a porosity controlled by the ratio of weight percent collagen solids to weight percent crosslinker when crosslinking the collagen. In other embodiments, the hemostatic compositions comprise crosslinkable collagen molecules having a porosity controlled by the temperature and rate of freezing when drying the composition during fabrication. In some embodiments, the compositions contain additional agents, including biological agents.