Pat GrandMaison from North Carolina is the winner of the Dragonfruit painting! She correctly identified the fruit, and gave the following added information:
The night blooming cereus is also called sweet-scented cactus, vanilla cactus, large-flowered cactus and reina de la noche (queen of the night) in Spanish. It blooms once a year, usually in late summer, and bears the largest flower found on St. John. The flower, which is white with yellow stamens, smells like vanilla and can reach as much as one foot in diameter. It opens up so quickly that you can literally watch it unfold right before your very eyes.
posted by Carmen