Asteraceae blooming daisies flower flowers garden gazania daisy petals pink plant plants treasure flower orange yellow white daisy petal spring african daisy Aster design flowering plant gazania lilac purple violet black brightly-coloured carpeting-plants clump-forming clumps colors colours common daisy-like drought-tolerant environmental-weed garden flowers garden-escape gazanias golden hardy introduced-species invasive lance-shaped leaves low-growing perennial prolific rapid-spreader resilient roadside-weeds South-African streaked tough vivid water-wise weed widespread wind-blown seeds color coloration colored colorful colour coloured colourful garden-flowers lance-shaped-leaves wind-blown-seeds brightly coloured carpeting plants environmental weed garden escape introduced species rapid spreader roadside weeds South African