Pitcher Plants

The closer you look, the more you see in pitcher plants (Sarracenia spp.). They're like creatures from another planet, with an eery, striking beauty, growing in a dizzying array of shapes and colors—and they have a gruesome dark side. Pitcher plants have not gone to finishing school. They have developed some bad eating habits; passive-aggressive carnivores, they turn the tables in a bug-eats-plant world. And this is just the beginning of the story of these sultans of the swamp.

There are nine or ten species of North American pitcher plants, all of which prefer open grassy savannahs, sunny coastal plains, and peat bogs. Almost all are native to the southeastern United States with the exception of one species, the purple pitcher plant (Sarracenia purpurea), which ranges into Canada. Many species stand tall, like sentinels, in their open habitats, with pitchers (tubular leaves) rising as high as three feet. The white-topped pitcher plant (S. leucophylla; pictured), the yellow pitcher plant (S. flava), and the pale pitcher plant (S. alata) are among the tallest. Others, like the parrot pitcher plant (S. psittacina) and the purple pitcher plant, have bug-trapping leaves no taller than six inches.

Regardless of their stature, all consume bugs for breakfast, lunch, and dinner. Some even have specific cravings, having become specialists in attracting and catching moths, ants, or other insect delicacies. Although pitcher plants are green and produce most of their own food the traditional way, using photosynthesis, they also gain nourishment from their captured prey. Pitcher plants and other carnivorous plants have evolved this capacity to catch bugs in response to the nutrient-poor soils in which they grow.

A DEADLY TRAP

Insects are attracted to nectar that each pitcher produces in its throat and around its rim. Ordinarily nectar is associated with flowers, but in pitcher plants leaves as well as flowers have adapted the ability to produce this sweet substance. Hungry flies, bees, ants, moths, and wasps wander deep inside the leaf in search of nectar. The steep and narrowing interior of the leaf is coated with a layer of loose waxy cells that are very slippery. Not knowing the danger they are in, many bugs lose their footing and fall deep into the rapidly narrowing tubular leaf. Struggle as they may to escape, most bugs eventually become exhausted and die. The pitcher plant is able to absorb nutrients and trace minerals from the “bug soup” that results as the insects decompose deep within the trap.

Bright, early bloom

Pitcher plant flowers are every bit as weird and beautiful as their leaves. They have been aptly described as being the shape of flying saucers or inverted umbrellas. Each is borne on a solitary stem that turns upside down as the waxy flower begins to open. The flowers hold great interest both in their beauty and in their duration.

Many pitcher plants bloom in early spring, before their leaves are fully developed. Petals of maroon, red, pink, acid yellow, or green persist for about a week. They are pollinated by bumblebees, which are one of the few insects strong enough to force their way into the flower's interior. After the petals drop, the seed pods and the remainder of the floral structure persist for the rest of the season, adding even more interest to these amazing plants.

Cultivars

As curator of native plants at the North Carolina Botanical Garden, I have been able to work with many fascinating groups of plants over the last 27 years. My interest in pitcher plants was piqued by our founding director, Dr. C. Ritchie Bell, who specialized in the study of Sarracenia.

By the late 1980s, countless thousands of pitcher plants had been poached from public and private lands. Collection of wild plants, along with habitat destruction, had placed this group of plants and many of their wild plant associates in grave danger. This combination of threats caused Dr. Larry Mellichamp, director of the University of NC-Charlotte Botanical Gardens, and me to launch a cooperative pitcher plant breeding program. Our purpose was to relieve collecting pressure on wild populations of pitcher plants by creating a demand for horticulturally superior hybrids. We engaged in a 10-year program to breed new possibilities in the world of pitcher plants.

Our initial efforts were energetic but unfocused. Through trial and error (and some good advice) we focused the direction of the breeding program. We sought plants that were vigorous, had excellent color, put on more than one flush of growth per season, and had good winter foliage. Keeping careful records and learning the value of ruthless culling were only two of the lessons we learned along the way. On many occasions our efforts were guided by pitcher plant guru Fred Case of Saginaw, Michigan, a pioneer in the taxonomy and culture of pitcher plants. His experience and support proved invaluable in helping us develop our hybrids, and our first cultivars, such as ‘Mardi Gras’ and ‘Dixie Lace’, were early successes.

More recently, the ‘Little Bugs’ series was released. All plants in this series are small in stature (10 to 12 inches tall), but diverse in form and color, bred as they are from a variety of parent plants. Their intermediate size makes them ideal for growing in containers. ‘Red Bug’, one of my favorites, is a vigorous selection that has a striking burgundy-red color on upright pitchers that are intricately marbled with an overlay of dark red veining. ‘Red Bug’ produces its erect pitchers in great profusion and has several flushes of growth each summer. It is the centerpiece of any bog planting and has a jaw-dropping effect on almost anyone who sees it.

Our latest hybrid pitcher plant, ‘Ritchie Bell’, was named in honor of the former director of the NC Botanical Garden. It is perhaps one of our finest hybrids to date, and perhaps our most complex. This hybrid has beautiful lettuce-green pitchers with undulating hoods suffused with rich dark burgundy and speckled with pearly white stars.

A small bog

In many ways, pitcher plants are best suited for growing in containers. Plastic pots or other nonporous containers are good choices. If your pot has drainage holes at the bottom, just place it in a deep, wide watering tray. I've seen some beautiful miniature pitcher plant bogs made by using a variety of plastic pots, dishpans, kiddy wading pools, and even porcelain sinks and bathtubs. If you want to make a larger pitcher plant bog, just excavate a depression 12 to 15 inches deep and fill it with a mixture of peat and sand. You can keep weedy seeds and soil from washing into your bog by placing it in a location that doesn't catch runoff from the surrounding garden.

This is one group of plants you don't have to worry about overwatering. If you are in doubt as to whether they need a drink or not, water them! But like many other members of the plant kingdom, pitcher plants don't care for water that is high in salts or minerals. Many growers use distilled water or collect rainwater for their plants if their tap water is mineral rich. It is also a good idea to take your pots out of their watering trays a few times during the summer and thoroughly flush them with a slow stream of water to wash away any mineral deposits that may have accumulated in the growing medium.

It is important to remember that pitcher plants are hardy native perennials that have periods of active growth and dormancy. They must have a rest period during the winter. Simply plunge your pitcher plant pots in the ground with the rim of the pot a few inches above soil level. With a little winter protection, pitcher plants are hardy as far north as USDA Zone 5.

No matter how you look at them, pitcher plants are captivating to both insects and gardeners. No sunny garden is complete without a few containers of these bug-eating denizens of the swamps. Even in the most diverse garden, they will steal the show.

Bug soup

Like all green plants, pitcher plants manufacture their own food by photosynthesis and absorb many nutrients through their roots. However, because of the low level of nutrients in the soils in which they grow, they have evolved the means to absorb nitrogen, potassium, and other elements from insects. To see what is really going on deep inside pitcher plants, researchers have labeled certain elements in bugs and then fed the insects to the plants.

Once a pitcher plant has captured an insect in its leafy trap, it secretes enzymes and fluids-not unlike our own digestive process. These work in concert with microbial activity to ‘digest’ the captured prey. The insect's soft body parts are slowly dissolved until only its hard exoskeleton remains. Researchers saw the tagged elements absorbed into the leaf and then traced them through many parts of the plants.

In the long haul, captured insects play an important part in the health and development of pitcher plants. However, don't succumb to the temptation of overfeeding your plants. They don't require many bugs to fulfill their nutritional requirements, and the few that they capture on their own when grown outside is more than enough to make them happy.-R.G.

Companion plants

Pitcher plants are striking on their own, but being native plants, they (and your garden) are best grown with companion plants that come from the same natural habitat as they do. Here are a few choices: