When flowersí ovaries ripen, they form fruit, sometimes along with accessory tissues. The fruit's composition depends on the plant's seed-dispersing strategy. It need not even be fleshy: From a culinary standpoint, nuts arenít fruits, but botanically, theyíre one-seeded, dry fruits with hard outer walls, like acorns or hazelnuts, that donít open when mature (pods open when they mature).
Sunflower seeds fruits called achenes. Like nuts, theyíre one seeded fruits that donít open when mature, but the seed attaches to the inside of the shell at one point.
Fleshy fruits are also distinctive. True berries, like autumn olives, currants, and ground-cherries, are thin-skinned fruits with seeds loosely embedded in a soft, succulent pulp.
Peaches and plums are drupes: One hard stone or pit encloses the seed. A pome, like an apple or pear, is a many-seeded fruit that doesnít open. Its fleshy portion comes from the receptacle, not the ovary.
Individual fruits may also fuse, the way flowers sometimes do: When the a flower cluster's fruits form a dense mass, you get a multiple fruit, like mulberries. If the bunch of fused fruits comes from one flower with multiple ovaries, you get an aggregate fruit, like a raspberry or blackberry.
When a fruit's fleshy part originates from a flower part other than the ovary, itís an accessory fruit: The strawberry's flesh, for example, comes from the receptacle. Itís an accessory fruit, while its seeds are achenes.