EVERY FALL, I BLEACH THE TEAK POTTING BENCH IN THE BACK OF THE GREENHOUSE, TO KILL ANY BACTERIA AND FUNGUS, IN PREP FOR THE COLD, DAMP CONDITIONS OF WINTER. DAMP POTTING SOIL AND WET CLAY POTS CAN EVEN ROT THE MOST TROPICAL OF HARDWOODS.
As winter approaches, the low angle of the sun and the short days and long nights, make every minute of sunshine, precious. Grumble, as we may about these long nights, without them, many plants will not form buds on schedule. I get asked so often about how I get certain plants to bloom which are notoriously shy about blooming as houseplants, and all I can say is that now that I have a greenhouse, I really don't think about this challenge anymore. There was a time when every October, we would moves the large pots of Christmas Cactus, Poinsettia and Clivia into the dark, cool cellar for a month, to 'trigger' bud formation. A move that rarely seemed to work well. But once we built the greenhouse, every plant blooms on schedule, give or take a few weeks.
I can look back every December on this blog, and see that my Haemanthus should be in bloom this week, (and it is). Clearly, day length is critical, and I would venture to say that it, along with temperature shifts, are the key triggers for bud formation with many plants. It does make one wonder, do humans respond to seasonal shifts in temperature and light? I mean, beyond the known benefits of light exposure ( which, I must admit, a sunny day in a winter greenhouse does wonders for those suffering from seasonal disorders, which Joe has, and I think that I do not). But I wonder if there are any other benefits from humans being exposed to natured elements that we not miss in our climate controlled homes?
AS YOU CAN SEE, THE FALL CAMELLIAS ARE STILL BLOOMING, AS IS EVERYTHING ELSE THAT SHOULD BE BLOOMING RIGHT NOW. THE ZYGOCACTUS ( CHRISTMAS CACTUS). WHEN GROWN UNDER GLASS, THIS PLANT RESPONDS NATURALLY TO THE SHORTER DAY LENGTH AND IT FORMS FLOWER BUDS WITHOUT ANY 'CELLAR TRICKS'. EARLY NARCISSUS ARE BEGINNING TO BLOOM, TOO.
EVERYTHING HAS A SEASON, AND POINSETTIA BLOOM NATURALLY IN MEXICO FROM AROUND CHRISTMAS THROUGH JANUARY. THIS WILD SPECIES FORM IS JUST STARTING TO FORM THE PLANTS ICONIC RED BRACTS.
The Poinsettia we see at the supermarkets are artificially subjected to short daylength periods earlier in the season ( draped with black plastic). At home, it is almost impossible to get a plant to rebloom unless you are prudent about daylength ( even a streetlight or a lamp can throw off the photo period). The above plant I have is actually the wild form of Poinsettia, or EUPHORBIA PULCHERRIMA. As you can see, it is just starting to form colorful bracts, which is normal for late November. In the wilds of Mexico, where this plant is native, the same thing is happening. When I lived in Hawaii, I remembered old Hawaiian cottages that looked very much like New England cottages, but instead of blue Hydrangeas, red Poinsettias were in bloom in January.
The plants we see now everywhere are not only hybrids, but drenched in growth retardant, which keeps them short enough for retail ( even shelves on shipping trucks are kept at certain height to maximize profits). So good luck finding a tall, old-fashioned poinsettia unless you know of a good florist who grows their own ( rare these days). The wild form is weedier, but I am fine with that. My only concern is as the weather cools down, the greenhouse will start to stay at around 40 degree's which is too cold for this genus, which prefers to stay above 50 deg. F. So I may move this, and a tree aloe which is forming a bud, into the studio for the winter, to see if that helps.