The Gory Facts about Carnivorous Plants

| July 9, 2016 | 0 Comments
Carnivorous plants have special mechanisms allowing them to trap protozoa, insects and other arthropods.

Carnivorous plants have special mechanisms allowing them to trap protozoa, insects and other arthropods.

When Mission Hills Nursery announced that there would be a talk on carnivorous plants, my first thought was, a new topic. My next thought was that the grandsons would love it. Both my grandsons are gardeners; Nic is 13 and is totally immersed in it. He has a thriving worm farm, recently installed a drip irrigation system for his raised vegetable beds, and is invited to help tend the school’s garden over holidays. Dan, age 10, is interested in whatever his brother likes. Carnivorous plants appealed to both boys.

We set out early for the nursery on a Saturday morning. We were early enough to hear Ash, a hen, cackling in her coop while the black hen brooded (sulked) on her nest box (All her friends were sold; she misses them.) and the butterscotch-colored fuzzy hen pecked at food and wandered around the coop. Ash was thrilled to be let out and promptly ran over to beg crumbs from the gathering audience indulging in donuts and orange juice. The resident cat wandered about, ignoring Ash, to the boys’ amazement. We sat with a surprisingly large crowd, mostly teenaged boys. My two and two Palafox grandchildren were the youngest in attendance.

Halia Eastburn and Trevor Adler gave us an overview of carnivorous plants. They explained that carnivorous plants are “just like other plants.” However, because they grow in areas with high light, in either acidic bogs or rocky outcroppings where the soil is bereft of or poor in nutrients, they are not able to absorb nutrients through their roots. Instead they have special mechanisms allowing them to trap protozoa, insects and other arthropods. The mechanisms vary, depending on the plant.

Some have “pitcher” traps. It traps prey in a rolled leaf full of digestive enzymes or bacteria. The pitcher’s rim is covered with intoxicating nectar. When the prey lands on the rim, he becomes disoriented or dizzy and falls into the opening. Pitchers may be too slick for escape. One carnivorous California native, the cobra lily, has a clear spot in the top of its pitcher. As a fly tries to escape, it falls more deeply into the pitcher and is doomed. The larger pitcher plants, such as Nepenthes rajah, occasionally catch small mammals and reptiles.

There are other means of catching dinner. One is with a “flypaper” device. The leaves act like flypaper keeping the repast in place until the nutrients from its innards can be extruded. Sundew, which is such a plant, propagates easily. Another method is a snap trap. The Venus fly-trap, for example, has hair-like protrusions on the edges of its leaves. If something disturbs two hairs within two seconds, the leaf snaps closed. The double hairs in two seconds means the plant won’t be trapping raindrops or dust particles whereas prey remains inside until it has been digested. Then the leaf will open again. Still another method of getting dinner is by sucking in prey. Bladderworts’ bladders have trigger hairs which open when stimulated. This creates a partial vacuum in their bladders which act as roots and a site for digesting prey.

Growing carnivorous plants should be easy, but it sounds complicated to me. In addition to needing critters for sustenance, they are unable to utilize tap, well, or bottled water. They need pure rain, distilled water, or reverse osmosis water as nitrates and other minerals found in our water will kill them. They may also get fungus from overhead watering. Giving them fertilizer, impure water, or watering them from above may cause sudden death. The best way to give them water is to set their pot in a shallow container of distilled or pure water. Let it dry a little, and then replenish the water,

They also need lots of light, several hours a day. However, their roots must stay cool. To facilitate this, white ceramic pots are ideal as white reflects light, therefore heat.

Since these flesh-eaters grow in poor soil in the wild, they will need a mixture of 70 percent peat moss and 30 percent nursery sand, or 80 per vent peat moss with 20 percent Perlite. In addition, these plants are prone to fungi. Most fungicides will kill your plant.

Adler continued saying that between October and late February these plants go dormant. They look as if they have died. “Don’t throw it out,” he cautioned. “It’s not dead; it’s dormant.” Just before the end of the dormant period is the best time to transplant them. When they come out of dormancy, they may have doubled in size. Many grow as much as an inch a day until they reach their maximum height.

The highlight of the morning was when Adler cut a leaf from a Sarracenia and split it lengthwise. The boys loved seeing partially and completely digested flies and other creatures. One newly ingested fly was still alive. My grandson Dan was very disappointed that Adler was unable to catch it and feed it to another plant.

My grandsons and I bought a Venus flytrap and a Sarracenia for each household. Nic saw his Sarracenia eat a fly its first day home. I put the Venus into the bottom of a butter dish of distilled water in the kitchen window since I saw a fruit fly there. She may have eaten it as one set of leaves is closed. My Sarracenia is out on the balcony dining table in an open orchid pot. Since the water is gone within hours, I set the entire contraption into a shallow pet dish. I suspect I am going to kill them both from too much care. Sadly I have become a serial killer of plants. I “off” one a week lately. Because my new plants eat flesh, I feel a sense of responsibility toward them. I might be better off without them! However, I have bonded with them… sort of.

There are no Garden Club meetings until September when it will be time to renew your membership. Happy gardening. And wish me luck.


Category: Local News

About the Author ()

Barbara Strona is a native Californian who grew up in the Mid-West and Los Angeles. She and her architect husband, Carl, came to San Diego in 1968 and have lived in Mission Hills since early 1971. Barbara received a Bachelor of Arts from Scripps College with a major in English, and a minor in Art. She attended UCLA graduate school and received a General Secondary Credential. She taught English in Los Angeles, Pennsylvania, and at Point Loma High School. She has been a Realtor specializing in residential sales since 1984. Her passions include her job, reading, writing, foreign languages and foreign countries, animals (feathered or furry), theatre, and her family: husband, two adult children and two grandsons.