Monthly Archives: November 2021

Every temperate carnivore shown at Triffid Ranch events has an ID tag that includes common name, Latin name, light requirements, a notice stating “Rainwater or distilled water ONLY,” and a second notice reading “Put into dormancy in winter.” The first question is always “so how do I put it into dormancy in winter? Do I put it in the garage?”

For the most part, in most places in North Texas, you can leave flytraps in dormancy in the same places that they frequented in summer. They still need full sun for at least 6 hours every day, and they still require rainwater or distilled water. They don’t need to stand in water, and in fact that’s a good way to kill them, so if you move your flytrap, move it to a place where its container won’t fill up with water during the inevitable winter rains. Otherwise, leave them outside: if temperatures threaten to get really cold, such as below 15F (-9.4C), move them to a place where they’ll be protected from wind, such as a covered porch, but otherwise leave them alone. Flytraps are mostly found in northern North Carolina (with patches in South Carolina and the Florida panhandle), so they’re adapted toward surviving rougher winters than anything we’ll see in North Texas more than once every 30 years or so. Whatever you do, don’t bring them inside for the winter: that winter dormancy is so essential for storing energy for spring that most temperate carnivores can survive a winter without that dormancy, but they generally won’t survive two winters.

The second question asked about dormancy is “how can you tell it’s gone dormant?” With most temperate carnivores, that’s easy: they stop growing and most of their trapping structures die off. Flytraps are a little more subtle, but just as fascinating.

The image above is of a clutch of the “King Henry” flytrap cultivar. “King Henry” is one of the largest available flytraps cultivars, and it’s specifically bred to produce oversized traps, usually at least twice the size of “typical” flytraps. During the summer, flytraps produce both short-stemmed traps that remain close to the ground and long-stemmed summer traps that raise well off the ground, and “King Henry” summer traps are some of the longest ones available. By the end of October in the Northern Hemisphere, the summer traps start dying off and shriveling up, and they won’t be back until the middle of May.

The summer traps may be collapsing, about now, but the traps around the crown of the plant are still growing for as long as temperatures allow. Even this late in the season, the traps may catch an occasional bug, but those bugs are going to be rare, and the trap may not get enough light to digest any prey that’s caught. All too soon, though, those traps will be there for nothing other than catching light, and older traps will even curl outward to maximize the amount of surface area able to intercept sunlight. Younger traps may still be able to close when stimulated, but usually no force on Earth will get a flytrap trap to close in the dead of winter, and you shouldn’t try, either. Even in winters so cold that the smaller traps die off, the crown of the plant remains green and continues with the mission of harvesting light.

About four months from now, we get to find out how successful dormancy was. This usually starts with new traps growing from the center of each plant, with older traps gradually dying off as they’re replaced by a new generation. If you’re really lucky, you may see a strange shoot coming from the center: these generally grow about a foot (about 30 1/2cm) high and then open tiny white flowers at the tip. Now you have something else to look forward to seeing in spring.

Here in the Northern Hemisphere, the days are shorter, the light is more diffuse, and the daily temperatures steadily head toward their average low, which means for most temperate carnivorous plants, it’s dormancy season. For American audiences, a good thumbnail for the duration of that dormancy is “from Thanksgiving to St. Patrick’s Day”: for everyone else, generally winter dormancy in the Dallas area is between the last weekend in November to the middle of March. Between that time, flytraps, North American pitcher plants, cobra plants, and temperate sundews, butterworts, and bladderworts slow down, die back, and otherwise settle in for a long winter nap. They don’t completely die back: most at least keep a few leaves in order to photosynthesize all winter, but they’re not bothering to attempt to capture prey because there’s little to no prey for them to capture, and the expenditure of energy on trap growth and digestive enzymes is more than what they’d get from converting water and carbon dioxide into sugar and oxygen.

Because of their slowing growth, winter is an excellent time to get temperate carnivores in order. Snipping off dead leaves to discourage animal pests is an obvious one, and if temperatures dropped early, as they did in Dallas this autumn, repotting and weeding is another. It’s also an excellent time to evaluate how the plant will get through the winter. If it’s in a pot that wouldn’t survive a hard freeze such as with our weeklong blizzard in February, now is a great time to move it out of said pot and into temporary accommodations that can handle a week or more of freeze stress. (Toward the beginning of March, when we’re reasonably sure that we aren’t getting a major storm, it can go back into the pot, with new potting medium, while it’s still dormant.)

Late autumn is also an excellent time to assess summer damage. The 2021 summer in North Texas was relatively mild and mellow until the beginning of September, when we had a combination of temperatures more typical for August and six weeks of strong winds and sunny skies, meaning that local humidity dropped through the floor until nearly Halloween. If we got rain, it was very quick, as in over and done in less than five minutes, so patchy as to be completely unpredictable, and rapidly evaporated in the south wind. Because of all of this, several flats of Venus flytraps intended for next year’s shows were badly burnt in mid-September, and they weren’t expected to live. The plan in November was to go through them all, toss pots where the flytraps were expired, and try to nurse the survivors so they’d get through the winter. Considering the damage, I expected maybe one pot out of every ten might be salvageable.

Well, in a classic example of “don’t throw out your plants until you KNOW they’re dead,” most of those burned flytraps came back. Flytraps and their sundew cousins regularly produce new plants from offshoots from their roots, and while the main plants burned off in September, their roots survived and came back. Fully eight of every ten not only recovered but produced whole clumps of tiny flytraps, happily catching as much light as they could.

The real surprise was the size: most of these could have passed for seedlings. Since they’re already established, though, most of these will reach full size by next summer, and let’s see what happens after that.

As for the greenhouse, it’s now full of a wide variety of Venus flytrap cultivars. I may need to schedule more shows to find homes for them all.