Anyone spotted any poinsettias yet? It won’t be much longer, though it is hard to believe the midwinter holidays are bearing down on us. Poinsettias, Christmas trees, Christmas cacti, mistletoe ... oh, wait, Thanksgiving first!
Right, Thanksgiving. Thanksgiving cacti and what? There are not many houseplants associated with this holiday. This makes sense. After all, Thanksgiving is supposed to be about harvesting, not growing new plants.
Actually, ’tis the time of year to look for — and buy — kalanchoe. That’s “kal-un-KOH-ee,” of the family Crassulaceae. The name is thought to be from the Chinese “Kalan Chau," which is what the Chinese called the native plants. There were also native plants found in Madagascar and South Africa.
These familiar succulents are becoming a seasonal houseplant for Thanksgiving because they bloom from October through March, when we have fewer hours of daylight during the days than darkness at night.
Kalanchoe are, then, perfect for us here in the north.
Today, kalanchoe plants are grown in outdoor gardens as far north as Oregon, just as they were in their homelands. However, in 1932 a variety of kalanchoe, “Blossfeldiana,” was introduced as a houseplant. It was slow going at first, but now growers and breeders are working the plant over, making terrific indoor specimens, as well as for outdoors where possible.
Besides the requisite darkness, our Alaska houses are perfect for kalanchoe because they do best with cool nights — as low as 40 degrees — and 60 to 65 during the day. They don’t need bright light either. So just push yours up against any window and you should be able to meet all the requirements for blooming.
Usually, kalanchoe blooms consist of several small flowers the size of rice grains, but sometimes larger -- the size of cornflakes. Some are single, some have layers of petals. There are now bell-shaped flowers, and I am sure breeders are working on more shapes and colors as you read this. Often they are fragrant. They last a long time. Yes, it is a collectable plant. Get the whole set!
When you buy a kalanchoe, it will be in bloom. However, these will fade, leaving deep green, serrated leaves. Ah, but it is always fun to have a few flowering plants around. Fortunately, kalanchoe can be forced into flowering.
Normally, these plants require a run of six weeks of darkness of 12 to 14 hours per day, every day, to develop new flowers. This is what happens every fall. However, you can produce flowers when the days are long by providing the dark hours.
If you are growing at home, you can use a box, paper bag or even an empty closet as a dark area in which to keep your plants during the necessary 12 to 14 hours. (The closet and a timer seem like the best way to go.) The trick is uninterrupted darkness. No street lights, as my dad would remind people. (He would also add, “not even a glowing cigarette,” but I don’t have to go there these days.)
You can also propagate your own kalanchoe. It is easy. Pick off a leaf and let the end where it was attached develop a callous by leaving it exposed to air. This will take a few days. Then put that end in damp sand, perlite, vermiculite or even soil. It will root in a week or so.
Kalanchoe soil should be slightly moist. A mixture of good compost potting soil and cocoa coir is ideal. A low number, liquid organic microbe food should be applied after flowering.
Jeff Lowenfels’ new book “DIY Autoflowering Cannabis” is available from Amazon.
Jeff’s Alaska garden calendar
Houseplant water: Room temperature is best. Let yours sit for a few hours to dissipate the chlorine.
Winter lights: Make sure yours are not damaging bark as a result of being too tight.
Bulbs: If you can work the soil, you can still plant them!