These stunning plants all have one thing in common: A taste for blood

Somewhere along the evolutionary timeline of bog-dwelling angiosperms, the plants gathered together and decided they wouldn't take it any longer.

No more would insects see plants as the ultimate salad bar. The time had come to fight back. The time had come for the plants to start eating the bugs.

All right, it may not have been that cinematic. Our favorite plant carnivores turned to meat because their chosen evolutionary niche - soggy and acidic peatlands, for the most part - didn't provide enough soil nutrients. And although this may be a more prosaic reading of their botanical origins, the way veggie carnivores have engineered themselves to consume animals is genuinely wondrous and amazes each generation that grows up to discover this phenomenon.

Michael Szesze was 10 in the early 1960s when he came across the bizarre Venus' flytrap, which appealed to young minds because it seemed to be a plant well on its way to becoming an animal. Not only did it digest insects, it clasped them like a bear catching salmon. It was animated.

“The concept of a plant that gets back at bugs got me interested,” he says. Almost six decades on, Szesze (pronounced sez-ee) has turned a 25-acre former Christmas tree farm - tucked away in the Catoctin Mountain ridge of Maryland - into one of the richest nurseries for carnivorous plants in the country.

Back when he was a Cub Scout, the mail-order flytrap was most likely the wild species that grows in the bogs and pine barrens of the Carolinas. Grade-schoolers ordered Venus' flytraps from their favorite magazines, and the plants would arrive and soon die from abuse, neglect or too much love. Monsters can be sensitive.

Today, for a number of converging reasons - the age of social media, the popularity of ecological gardening and the breeding of variants - the interest in carnivorous plants has never been more intense or widespread.

Szesze, 65, fills about 50 orders a week, and the success of his nursery, he says, is testament that “it's not just geeks buying the plants.”

He shows me the oddities growing in the benches of his 900-square-foot greenhouse. From one species of Venus' flytrap - there is only one species, Dionaea muscipula - breeders have gone to town, and Szesze's Carnivorous Plant Nursery sells more than 30 varieties. Their names suggest their attributes - Shark's Teeth, Red Piranha and Fang among them.

Virtually every aspect of the flytrap species has been altered by hybridizers. The hinged traps are bigger or smaller, they're redder or greener, the guard hairs are longer or miniaturized, and so on. These subtle differences captivate collectors. Among those with the largest traps - approaching the size of a half dollar - are King Henry and B-52.

The greenhouse benches are full of other jewels, including butterworts and sundews. Butterworts resemble fleshy leafed succulents, but when you study them you see tiny dewlike droplets on the leaves, which are the eating apparatus for their meal. In his home, Szesze keeps one near the banana bowl to take care of fruit flies.

Sundews are found around the world, and they come in different forms, but they are all distinguished by tiny hairs capped with a sticky secretion that ensnares the prey and then absorbs it. They are typically ground-hugging, such as the pinwheeled pink sundew, found in Southeastern states. Species from the Southern Hemisphere can be conspicuously taller and branched, no doubt to catch flying food. In one section of the greenhouse, Szesze points out staghorn sundews from New Zealand, whose tentacles are borne on antenna-like stems.

The greenhouse is used for propagating plants and as a home for the tender carnivores that wouldn't survive a winter outside.

These include the tropical pitcher plants, many of them tree-dwelling vines, and with pitchers so large and sinister-looking that they have enthralled Western botanists for centuries.

I am partial to hardy North American pitcher plants, if only because they are some of the prettiest perennials in the garden. They are conspicuous with alien-looking nodding flowers and hooded pitchers of exquisite form and patterning, rising to 36 inches or taller.

The pitcher plant's showy flowers are held aloft like balled flags, facing down from tall stems. They bloom before the pitchers fully emerge - it wouldn't do to eat your pollinators. Some flowers are acid green, some maroon and some a deep crimson. They are all spectacular.

Three species have provided the most commonly grown decorative varieties and hybrids. Sarracenia flava, the yellow pitcher, has chartreuse flowers and pitchers, though often with marked venation and natural variation. It is native to southeastern states but is hardy in a swath of the East Coast that stretches to Massachusetts (hardiness Zone 6).

Sarracenia leucophylla, the white-top pitcher, is another southern pitcher and perhaps the showiest, with the white upper areas of the tubes contrasting strikingly with darker venation. Fanciers refer to these patterns as windows.

The purple pitcher plant, Sarracenia purpurea, is a northern species but quite different: The pitchers are low, squat and clustered.

All three species - and their variants - are winter hardy in the Mid-Atlantic, as are flytraps and many sundews.

On the grassy slope above the greenhouse, Szesze has arranged most of the pitchers and other hardy plants in 24 flooded growing beds, most of them 4-by-16-foot, rubber-lined troughs. The bulk of his 10,000 plants inhabit this outdoor realm.

A measure of how the pitchers have been developed by breeders is that he has purple pitchers that are yellow and yellow pitchers that are purple.

The tubes lure insects with sweet secretions, but once the creatures lose their footing and fall into the tube, enzymes consume them. (Cue sinister laugh from Vincent Price.)

Yellow pitchers produce two or three pitchers in the spring, but their main season of display is from late summer into fall, when an established clump might put up a dozen tubes.

Szesze is tall with silver hair and mutton chops; his is the sort of patrician head to have graced a Victorian coin. His path to carnivorous plants may have started when he was a boy, but it formed later in a career in public education. As a high school science teacher, he figured out that carnivorous plants would enliven his classes on botany.

Much of the native habitat of carnivorous plants is under threat; reputable nurseries propagate without harming wild populations. Once you explain the natural growing environment of the flytrap or sundew to students, “they immediately understand the value of the wetlands,” he says.

“I would give talks at teacher conferences about how to use the plants to motivate students. A common question was, 'Where can I get some of these plants?' It dawned on me what the answer should be.”

Szesze and his wife, Pamela (also a teacher), established the nursery in 2004 from their home in Rockville, Maryland, but moved to northern Maryland more than five years ago when they both retired. Their property, which has a Smithsburg address, is a few miles west of Camp David. The nursery is open by appointment.

They also sell companion plants that grow in moist environments, including such delicate beauties as gentians, bog orchids, two species of violets and even cranberry shrubs.

Growing carnivorous plants

If you don't have a greenhouse, and most people don't, there are three basic ways to grow most carnivorous plants, as long as you are in plant hardiness Zone 6 or warmer.

• Indoors: Some carnivorous plants simply are not suited to indoor environments, though a few tropicals will work as windowsill plants if, in winter, they can be kept humid and away from direct heating or cold drafts. However, a terrarium with its own supplemental lighting is a better environment. Temperate plants should be allowed to go into dormancy during the winter by reducing water, temperature and light levels.

• Outdoors in containers: This is the easiest way to grow hardy bog plants, but make sure the pot is big enough. A container that is too small will stress plants in winter (from freezing) and in summer (from evaporation). Szesze suggests a pot at least 10 inches across, and, of course, it has to be of material that is freeze-proof.Szesze makes small gardens for patios with a medley of plants in low, broad plastic containers. He drills quarter-inch drainage holes on the side of the pots, just 1 inch or so below the lip. This allows the soil to remain saturated without flooding the plant crowns.

• In a bog or raised bed: Building a bog garden is no small feat. You have to bring in large quantities of sand and peat moss and devise a way to keep it moist; the installation costs can add up.Instead, you may want to consider a raised bed. Szesze has built an elevated display garden at his nursery, a five-sided timber-framed bed measuring roughly 8 feet wide and 10 feet long. It is well stocked with various pitcher plants, bog orchids, violets, gentians, sundews and flytraps. It took 12 wheelbarrow loads of soil.If you have an existing pond, you could fashion a bog at its margins, though it would have to be free of any fertilizer runoff from surrounding areas as well as the buildup of fallen leaves or other organic matter.I have my pitcher plants growing in pots on a planter ledge in my fish pond, about four inches below the water line. As long as the water doesn't get too high — and certainly not above the soil line — the plants are happy.Care and feedingHow do you kill a carnivorous plant? By treating it like just another garden perennial or houseplant.• Plants will die in conventional garden or potting soil, which is too rich. Use a mix of one part sphagnum peat moss to one part sand. Living sphagnum moss — the generative material of a peat bog — can work as a mulch, much as it would in a natural bog.• You can't use municipal water, which has too many minerals. The choices are collected rainwater, distilled (not bottled) water or well water.• Feeding with fertilizers, including organic fertilizers, will also imperil the plants. Plants do need an insect meal, but only occasionally, and when outdoors in the garden they probably can feed themselves. Growers of indoor plants can use freeze-dried insects from a pet shop or wingless fruit flies.• Don't use raw meat or cheese, says Szesze, which will rot, kill leaves and compromise the whole plant. Flytraps need to feel a struggling insect to fuse their leaves for the meal, he says.• Closing a trap takes an enormous amount of energy, and if all that work is not rewarded with an insect, the plant is weakened. “The worst enemy of the Venus' flytrap,” he says, “is a kid finger-poker.”