Botany Photo of the Day

(Eric La Fountaine of UBC Botanical Garden and Centre for Plant Research has kindly guestblogged today -- Daniel)

I came across these delicate frameworks around the base of my compost pile in spring. They are the remnant husks of Physalis fruit, after enduring several months of decay. I was struck by the intricate pattern, so created this image using a flatbed scanner.

There are at least eighty species in the genus Physalis. Tomatilloes (Physalis ixocarpa), a tomato-like fruit used in Mexican cuisine, and the ornamental Chinese lantern (Physalis alkekengi) may be the most familiar. Part of the nightshade family, the plants are generally poisonous, though the ripe fruit is sometimes not.

My memories of our garden as a child include Physalis (likely Physalis pruinosa, one of the species commonly known as “ground cherry”) coming up spontaneously from seeds that dropped with the previous year's fruit. I thought it was one of the most wonderful plants for fruit harvest. When ripe, the berries fell to the ground and we gathered them with rakes. Each berry had a protective papery husk, which made for easy storage and clean fruit when popped from the shell. My mother thought that our seeds had come from Europe with the family. This is possible, but the plants are native to the Americas so it may have been added to the family garden after immigration. We always enjoyed an abundance of this fruit -- it has been described as a mix of pineapple and strawberry -- and my mother won prizes for her “ground-cherry pie”.

Not all Physalis species drop their fruit like the ground-cherries of my youth. The species in the images, purchased at a small fundraising sale, had fruit which held fast to the plant even when fully ripe; in fact I had to cut them off. I believe the plant to be one of the tropical species, perhaps Physalis peruviana or Physalis angulata. The flavour and size of the fruit of this species was superior to the fruit harvested by my family. I feel fortunate that a most welcome supply of seedlings popped up in my garden this spring, filling me with anticipation for this autumn's harvest of this sweet treat.

For different versions of this scan, see this thread in the UBC Botanical Garden Forums.

Update (July 20, 2005 11:23 AM PST): As requested by one of the commenters, here is a 1280 x 1024 version and the original 4125 x 3300 version (8MB in size!).