Backstory: it’s January, we don’t have any distractions, and the plants need us. Therefore, it’s time to discuss methods to clean up carnivorous plants for spring. For details, go back to the beginning.
And now we get to the most labor-intensive carnivores, as January marks the perfect time to clean them up for spring. North American pitcher plants (Sarracenia spp.), as carnivores best raised outside, should be quite dormant by now if you’re raising them in the Northern Hemisphere, and Dallas’s mild winters don’t determine that dormancy so much as the short days. As of the middle of January, we still have two months where temperatures and precipitation can fluctuate all over the place: we could have springlike temperatures between now and the end of April, or we could get hit with a week of subfreezing temps and repeated sleet storms. Either way, Sarracenia sleep through it all, only starting to produce bloom buds around mid-March (I tell locals “wait until St. Patrick’s Day”) and new traps in April after the blooms have been pollinated. (Most of the insects most likely to gather Sarracenia pollen are the fully revived plants’ prey the rest of the year, so the overwhelming majority produce their traps well after blooming. The only serious exception is the yellow pitcher plant, Sarracenia flava, which tends to bloom early and produce big traps when other species are just opening their blooms. That antisocial tendency continues: most Sarracenia blooms smell sweet, but S. flava blooms are best described on a range between “cat pee” and “eau de anime convention,” and the fragrance, if you can call it that, can be overpowering in close quarters.)
In this example, we’re looking at a Sarracenia “Scarlet Belle,” a hybrid of S. leucophylla and S. psittacina, and a great example of the variation in Sarracenia leaf morphology. In the center are the last traps of autumn, sprouting when temperatures in Dallas went from “skinnydipping in a lead smelter” to “actually not half bad,” and those pitchers are particularly brightly colored in order to attract available prey before all of the insects in the area die or go dormant themselves. On the outer edge are the remnants of last spring’s growth, with some of these being survivors from the previous year. In between are leaves with tiny or nonexistent traps and a big wide ala or “wing” growing from the underside. These leaves are called phyllodia, and Sarracenia usually grow them in summer, when it’s too hot to do more than photosynthesize. North American pitcher plants also grow phyllodia in late fall, and for the same reason: to capture as much light as possible over the winter in order to have plenty of stored energy in spring for growth and blooming. If all you have are phyllodia, that’s usually a sign that your pitcher plant is being kept somewhere far too dry, with too little light, or both.
For this exercise, the following tools or their analogues are highly recommended:
- Garden mat or old towel
- Isopropyl alcohol, bottle or wipes
- Hand cloth or paper towels
- Spray bottle filled with rainwater or distilled water
- Narrow garden shears or garden scissors
- Long tweezers or alligator forceps
The first thing we’re going to do with this cleanup is remove or trim dead and dying leaves. Many older traps will just pull free with a gentle tug: if it doesn’t come free with a gentle tug, don’t yank harder to get it free. Sarracenia have deeper and stronger roots than, say, Venus flytraps, but relatively fresh leaves can still be stronger than the roots, and you don’t want to rip the plant apart by being overly enthusiastic. If it pulls free right away, go that way, but otherwise cut it free. With everything, remember “if it’s brown, it can go,”, because dead leaves won’t magically become green again in spring. Feel free to trim back pitchers and phyllodia with dead ends, but try not to cut into still-living portions if you can help it.
With the dead detritus cleared out and dumped in the compost pile, take a look at the still-living pitchers and phyllodia and look for pests. Slugs regularly hide among and within dead pitchers, and scale insects will grow between the main pitcher and the ala, die during the winter, and spread fresh hatchlings from their cases in spring. Scale can be treated with neem oil, either sprayed or applied gently with a cotton swab. Other than that, look for anything else that might be off and keep notes to check on these over the rest of the winter.
Since your pitcher plants should be outside, this means that outside seeds can get into the pot, whether by wind, by animals, or by interesting seed dispersal mechanisms. One of the most common is clover of all sorts, as clover does very well in the low-nitrogen soils of bog plants. Here in Dallas, we have two major aggravations besides clover: cottonwood seedlings, which sprout pretty much anywhere so long as they have access to water, and violets, which take over in the colder part of the year. Cottonwoods have to come out no matter what time of the year it may be, but violets tend to burn back in summer, making it very hard to tell how bad an infestation can be until winter and early spring. Violets are more annoying than anything else, so removing them from your outdoor carnivores isn’t an absolute necessity: considering how fast cottonwood trees grow, you want to remove those as quickly as possible.
No matter when you conduct your Sarracenia cleanup, plan a followup sometime in February to look over everything with fresh eyes. Traps or phyllodia that weren’t dead in January may be dead in February, and overlooked weed seedlings should be just big enough to be noticed in a month, especially if temperatures didn’t go well below freezing. While you’re at it, schedule another followup for the beginning to middle of March, and if you’re lucky, you’ll see little nodules on stalks, looking like a snail’s eye, growing from the center of the plant. Leave those alone, and they should rise up, droop, and spread their petals within the next month or so. And the cycle continues.
To be continued…