We report on the growth of whisker-like TmBa2Cu3O6+x (Tm-123) single crystals which are especially suitable for studying the anisotropic electron transport. We have found that the formation of Tm-123 crystals from the flux starts with the growth of skeletons (dendrites), and their familiar plate habit develops through the following skeleton overgrowth. Incomplete growth results in large clear dendrites, whose branches are exotic whisker-like single crystals with sizes up to 50 x 1200 x 600 mum(3) with the bc-face being the largest one.