background circle cluster flower group head pattern plant Sardinia symmetrical symmetry texture umbel umbellifer white alpine canada coast conifers flora flower-head landscape meadow mountains natural nature seed seedhead slope stalk sub-alpine trees view Whistler allium ball England english flowers garden Great Britain onion ornamental pink purple stem trellis bright colorful colourful flamboyant flowerhead orange petals rich summer sunflowers yellow Dandelion petal spring Surrey Taraxacum uk united kingdom brassica canola crop farm field napus oilseed rape Sussex abundance abundant coneflower Echinacea many profusion artichoke blue Cynara mauve vegetable