It’s frigid outside, but with a little help from LP gas (OK, a lot of help), it’s the tropics in my greenhouse. This week, the star is a seed-grown Hippeastrum calyptratum bulb, flowering for the first time four years after germination.
H. calyptratum is a very unusual amaryllid from the Atlantic Forest of southern Brazil, where it grows as an epiphyte on tree trunks. The pale green flowers are pollinated by bats and are often reported to produce a odor like burning plastic. To my nose, they smell more like wet paint, but the fragrance is not very strong–at least not from this seedling.
There are two (possibly three) other epiphytic Hippeastrum species. I previously posted on H. aulicum when my plants bloomed in autumn. The third epiphytic species, H. papilio is currently blooming a few feet away from the H. calyptratum, and a different clone bloomed earlier, at the same time as my H. aulicum.
The fourth epiphyte, H. arboricola, is rather mysterious. It was apparently described from a single plant found growing on a fallen tree in a clear-cut forest and has not been seen since. It is not clear if H. arboricola represents a distinct epiphytic species, possibly now extinct, or if it was a terrestrial species that was growing opportunistically on a tree.
H. aulicum and H. papilio are large, robust plants, very easy to grow in a mix of commercial potting soil and permatill (stalite). When I tried that mix with H. calyptratum, the plants did well initially but later lost their roots. In some cases, the entire basal plate rotted, destroying the bulb. I now use a very open, wholly inorganic mix of scoria (red lava rock) and permatill in terracotta pots and have much better results. As befits an epiphyte, I plant the bulb high in the pot, with just a few large chunks of scoria holding it in place. The roots are quite happy to wander around on the surface of the mix.
Assuming that my blooming plant is close to full size, the bulbs of H. calyptratum seem to be significantly smaller than those of H. aulicum and H. papilio, and the leaves are proportionally shorter and narrower. H. calyptratum shares with its larger epiphytic cousins a growth cycle that is quite different than that of the Hippeastrum (“Amaryllis”) hybrids sold for forcing in winter. H. calyptratum has a short dormancy in mid-summer, but it retains some of its leaves and does not want to be bone dry for long periods while dormant. As temperatures cool in autumn, my plants begin growing again, and they continue producing new leaves intermittently through the winter.