Crown of Thorns Gourd Seeds. Unique claw-like projections form on small colourful gourds. This is a good selection for small gardens as the vines are quite compact. Fruit colour varies from cream, yellow, orange to green with stripes. The gourds average about 10 cm (4″) across. When the stems turn brown and dry, the gourds are ready for harvesting. If you are cramped for space, gourds easily lend themselves to growing vertically on a trellis or other supporting structure.