clingstone colorful coloring colors colourful colouring colours cultivars edible firm food fresh fruit healthy jam juicy kernel nutritious orchard fruit pit plum plums Prunus purple red ripe Rosaceae seed skin smooth stone stone fruit sweet tasty tree fruit variety various whole aroma color colour delicate drupes nectarines peaches prunus-persica-var.-nectarine smooth skin stone-fruit tree-fruit prunus persica var. nectarine whitish flesh furry orange prunus persica yellow abundance prunus-persica quality quantity tray fruit-tree green growing growth leaves prunus-persica-nectarine ripening Unripe donut peach doughnut peach flat flattened