Distinguishing traits. Thanksgiving cactus and Christmas cactus are both flat-leaf cacti native to the tropical forests of Brazil, but they're different in subtle ways. Thanksgiving cactus has pointed or claw-like stem ends, while those of the Christmas cactus are rounded.Thanksgiving cactus also begins to bloom earlier, setting out buds in mid to late fall with flowers in white, fuchsia, pink, red and salmon. Most plants bloom profusely from about one month before Christmas until later in January or even into February.