Monday, November 14, 2016

Conophytum Flowers

Conophytum plants in flower. Conophytum cubicum up front with white flowers, C. burgeri pink at left, C. irmae yellow at front right, etc. etc.
  Here in New England, we're just reaching the end of the main flowering season for Conophytum (family Aizoaceae), my favorite group of dwarf succulents from South Africa (and slightly into Namibia). These plants grow during the cooler, shorter-day part of the year, and the majority of species bloom at the start of the growing season. For me, that's October, but in their native Southern Hemisphere habitat, they mostly bloom in April. A few species bloom earlier or later in the year, and a couple, like Conophytum bachelorum (purple plants at front left in the photo above), strictly flower in the late winter and spring.

More Conophytum flowers at a University of Connecticut greenhouse, October 2016.
The 100 or so species of Conophytum show a tremendous range of floral colors, but in all cases have a floral tube with a supply of nectar as a reward for pollinators. The tube is formed by the fused bases of the petals, which, technically, are thought to be modified stamens ("petaloid staminodes") in this family. The brightly colored daytime flowers that are most obvious in these photos are probably pollinated primarily by bees, long-tongued nectar drinking flies, and butterflies. They open on sunny days, close up at night, and tend to have only a faint, pleasant smell.

A number of species, like Conophytum calculus (grey-green spheres at lower left in the second photo), have nocturnal flowers that open fully after dark and produce strong sweet and spicy fragrances. Nocturnal Conophytum flowers are frequently a pale, dull yellow or straw color, but white, pale pink and dark bronze also occur. Nocturnal Conophytum flowers will only open properly at night if it has been sunny during the day. On the night after a dark, cloudy day, they remain closed, in what could be an adaptation to prevent the flowers from getting ruined by rain.


Rika said...

Beautiful plants and flowers! Thank you for sharing :)

Anonymous said...

Can the flowers be self-pollinated?

Matt said...

Anon: A couple of species, like C. rugosum, can sometimes be self-pollinated, but the majority will not set seed without getting pollinated by another individual.