Don't Taste the Rainbow

Amorphophallus bulbifer is ripening a lot of fruit this year, at the UConn EEB greenhouses. In spite of appearances, and the fact that birds or some other animal disperser probably eats them, it would probably be a bad idea for a person to sample these berries. Amorphophallus is an aroid (family Araceae), a group known for being toxic to humans. In many aroids, all parts of the plant contain microscopic calcium oxalate crystals, which irritate the lining of the mouth and throat, causing intense pain and swelling that can be life-threatening if the airway becomes constricted. In some aroids and for some people, the crystals can even cause pain and rashes on the skin of hands exposed to sap from cut plant parts.

Snow Days

The past year has been a strange one for weather. Last summer was the hottest on record in the northeast U.S., and this January is going to be the snowiest month on record for some parts of Connecticut. Well, it's been a good test of the house I moved to last June, whose heating, cooling, snow removal and general structural characteristics seem to be adequate under extreme conditions.


I enjoy a certain amount of snow, but this winter is getting kind of traumatic. I'm wondering where I'm going to shovel it to, if we get much more. Well, the roof is cleared off in anticipation of tomorrow's storm, and late-winter flowering bulbs like Freesia are doing their thing in the UConn greenhouse, so spring isn't too far off. We're gaining more than two minutes of daylight every day in my area, and the sun is noticeably stronger than it was a few weeks ago. By mid-March, any sort of serious cold or snow is very unlikely here. Six weeks to go!

To get the Connecticut Cactus and Succulent Society in the mood for spring, the February meeting (Sunday the 6th) will feature a program by Devan Parker about starting seeds under artificial lights. On February 19th, I'll be giving a talk to the Cactus and Succulent Society of Massachusetts about Conophytum, everyone's favorite genus of winter-growing succulent plants. And at the end of the month, Nutmeggers can look forward to the Connecticut Flower and Garden Show, where I'm giving a demonstration about succulents for the windowsill, and a slide show about Pelargonium (geranium relatives). The time until spring will fly by, I'm sure.

Viscum minimum: a Dwarf African Mistletoe

Viscum minimum fruit emerging from its host.

Parasitic plants, which obtain some or all of their water and nutrients by attaching to a free-living host plant, seem to be unusually well represented in the floras of desert regions. Mistletoes (genus Viscum), probably the most familiar of vegetable parasites, may be encountered in arid places (and elsewhere) in the old and new worlds. Mistletoes are usually hemiparasitic, meaning that they extract water and minerals from their host, but are green and can manufacture some of their own nutritional needs via photosynthesis, like ordinary plants.

Viscum minimum is a minuscule mistletoe endemic to South Africa, where it grows inside of the succulent stems of euphorbias. Most of the time, V. minimum grows internally, with no indication of its presence on the exterior of the host plant. However, when it reproduces, the mistletoe’s greenish flowers and showy orange-red berries break through the euphorbia’s skin, in order for pollination and seed dispersal to take place.

Old plant of Euphorbia polygona ‘Snowflake.’

Viscum minimum is one of the few types of mistletoe that is ever cultivated outside of its native land. The host plant, usually Euphorbia polygona, is an easy to grow and attractive addition to a greenhouse or windowsill succulent collection. The mistletoe, which can be acquired either in the form of an infected euphorbia cutting or by smearing fresh, sticky seeds onto the surface of a suitable host, doesn’t cause significant harm to its host plant, and will produce crops of colorful fruit in time for the holidays year after year.

Frozen Flytraps

Connecticut got its first slushy snowfall of the season yesterday, and I took this photo of the Venus' Flytraps (Dionaea muscipula) in pots outside of the UConn biology greenhouses. They'll be fine, and can in fact take quite a bit more cold than this. Flytraps aren't tropical plants at all, and in their native land (the coastal Carolinas), they are dormant in winter and receive a fair amount of frost, and the occasional snow. New England winters might be too much for them, though, especially fully exposed to the elements in pots out of the ground, so I'll soon move them to a refrigerated room (temps just above freezing) for a couple more months of cold dormancy.

Planted in the ground, Dionaea can sometimes survive winters in southern New England, even without mulch or other extra protection. I've seen plants make it through several years in local bog gardens, though they seem to suffer a bit in colder than average years, and don't come back in spring 100% of the time. With a mulch of pine needles, they seem to be pretty reliable.

Eriospermum paradoxum

Cool nights and shorter days mean that winter-growing succulent plants are becoming active. Here is a pot of Eriospermum paradoxum, a tuberous plant from South Africa, blooming in cultivation in Connecticut. The flowers have a very strong fragrance, reminiscent of narcissus. After the flowers are finished, the tubers produce small leaves with a branched outgrowth that resembles a miniature Christmas tree. The leaves last until April or so, gathering weak winter sun to fuel the growth of the subterranean tubers, which will survive the summer heat in a dormant state before flowering again next autumn.