Carnivorous Plants: A brief overview

Jess Golden
Adams County Master Gardener

Plants require three things at the simplest level: sun, water, and nutrients. What happens when one of those essentials just aren’t present in some environments? They adapt. One of the most fascinating adaptations, in my opinion, are carnivorous plants. Carnivorous plants have adapted to be able to live in nutrient deficient wetlands. Instead of receiving the vital nutrients from roots in soil, the plants have special ways to attract prey insects and turn them into nutrients. The most well-known being the Venus Flytrap.

Occasionally, you can find these plants at your local gardening center. The disappointment of bringing one home and following the care instructions, only for it to die a few weeks later, is frustrating. The hard truth is that Venus Flytraps are sold as a novelty with no real expectation for long term growth. Doing a short skim through a few carnivorous care websites will reveal that, with a little forethought, most native carnivorous plants are low maintenance and easy.

All carnivorous plants are found in a bog or swamp environment. They require soil with very little to no soil nutrients or fertilizers. An easy to find substrate is 1 part sphagnum and 1 part sand (washed play sand, not landscaping or construction sand). Be very sure that the soil mixture contains no fertilizers. Most pre-mixed soil will have a fertilizer included. Too much of a good thing is a bad thing, in this instance. Carnivorous plants have adapted to catch insects and digest them into a usable fertilizer, of sorts.

There are many different ways to DIY your own mini-bog. Once you have your soil mixture ready, plant the carnivores in a pot with good drainage. Nursery pots work well, try to stay away from terracotta and ceramic. They could leach minerals into the soil. Once potted, sit them in a non-draining container. My mini-bog makes use of an old casserole dish that wasn’t being used. Add distilled, reverse osmosis, or rainwater into the non-draining container until it’s about half-way full. And there you have it! A mini-bog! Replenish the water when needed, making sure to use one of the three waters stated above. Keep them in full sun. Many people think you need to feed your carnivores but it’s really unnecessary. My collection stays outside for the summer and seem to do fine with what they catch out there. Keep them outside for the summer and then bring them in before the first frost. You can leave them outside and let them go through a dormancy phase. I bring them inside and put them in my draftiest window, so they’re cold enough to go dormant, but not freezing.

There are a few different types of carnivorous plants. The most well-known is the Venus Flytrap (Dionaea muscipula). Some are familiar with Pitcher plants (Sarracenia purpurea, locally). The last two types are called Butterworts (Pinguicula) and Sundews (Drosera). Venus Flytraps have clam shell looking leaves with "hairs" on the inside to trigger the leaves to close when insects rub them. They then digest the insects to create the nutrients they need. After a few days, the trap will open back up. Pitcher plants are taller and, as the name suggests, look like a tall cup. The leaves are hollow with liquid inside. The lip of the pitcher has a slimy film on it so bugs slip right into the pitcher and can’t climb back up. The liquid inside digests the insects. The lesser-known carnivores are Butterwort and Sundew. Butterwort look like succulents. They lay flat on the soil in a rosette. Each of the leaves are covered in a sticky film. When they have prey stuck in the sticky film, the leaves roll around the prey. Sundews are long stalks with droplets of sticky fluid. When the prey gets stuck, the stalk curls around them.

There are a good many species of carnivorous plants that do well in our growing zone. We live in zone 7. Venus flytraps are hardy and do well. A good pitcher plant species is the American Pitcher (Sarracenia). As the common name suggests, they are native to North America and are the provincial flower of Newfoundland and Labrador, Canada. Butterwort species that are well suited for zone 7 are the Pinguicula species. I’ve personally found the butterworts to be a little less hardy than the others. Lastly, most Drosera species of sundews are hardy enough to be kept in zone 7.

Scientists still aren’t exactly sure how some of the carnivore’s function, such as the mechanism that closes the Venus flytrap, but it’s fun to watch. Currently, all the carnivorous plants are under strict laws to protect them in their natural habitat. Much like cacti, leave native wild carnivorous plants where they are. There are a variety of reputable nurseries that carry carnivores online. Whatever you choose, carnivorous plants are an interesting addition to any collection.

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