Adaptation Aeonium tabuliforme Canary Islands crassulaceae green greenhouse nature plant rosette saucer spiny tropical vegetation abstract Aeonium appearance background color colored colour coloured contrast contrasting cultivar decorative evergreen garden greenery monocarpic ornamental pattern patterned patterns perspectives plants rosettes saucer-plant shape shapes stem stonecrops subshrub succulent surface surfaces symmetrical symmetry texture textured textures tree-houseleek variations variety