Mespilus germanica – Medlar is a small deciduous tree (to 20′ tall) with 2″ wide white to pale pink blooms in late spring. These are followed by spherical brown fruits (up to 2″ across) that are not ready for eating until they have received a hard frost in late fall. A favourite of the ancient Romans, the over-ripe fruit has a taste reminiscent of apple sauce. Self-fertile. Zone 6 hardy.
Decaisnea fargesii – With a common name of Dead Man’s Fingers and an edible jelly (inside the blue sausage-like fruit) that has the look and consistency of snot, it’s not too surprising that few people have tried eating it. The taste is like Lychee Nut and black seeds are not eaten. This fruit hails from an ordinary looking large shrub or tree (to 20′ tall) with green flowers. Self-fertile. Zone 7 hardy.
Cydonia oblonga – Common Quince (not be be confused with flowering quince or Chaenomeles) produces round or pyriform fruit that ripens in autumn. Although quite hard, the fragrant fruit is used to create a fabulous jelly and is also traditionally cooked with pork. The 15′ tall tree is quite attractive with downy foliage and white to pale pink blooms. Self-fertile. Zone 5 hardy.
Akebia quinata – Like Decaisnea, Chocolate Vine or Akebia quinata is a member of the Lardizabalaceae family. It is a vigorous vine, growing 20-30′ long with five rounded leaflets and tiny purple flowers (fragrant) that begin as an orb, and open to three rounded petals. The elongated pink 4″ long fruit is a rare occurance – these split open to a surrealistic sky-blue interior and edible jelly surrounding black seeds. Requires cross-pollination from a different clone within the same species. Zone 6 hardy.
Solanum integrifolium – Pumpkin on a Stick is more commonly seen as an ornamental accent in cut flower arrangements, but the fruit is actually edible. Related to eggplant, it is occasionally used in Asian cuisine. This plant is hard to find and you’ll probably have to grow it from seed, as it is annual in nature. Solanum integrifolium grows 3-4′ tall, has purple stems and thorns. Self-fertile. Annual.