I fill prescriptions all day, and some habits are hard to break, so here's everything I know about keeping carnivorous plants alive, laid out the way I'd want it on a label. Most of it is about Venus flytraps and pitcher plants (Sarracenia), because that's what most people have and what grows best around here. The other kinds are covered in the chart at the bottom. These are the things that work for me in Wilmington. If you live somewhere with real winters, read the dormancy part twice.

Use: rain water, distilled water (a gallon jug from the grocery store is cheap), or water from a reverse-osmosis filter.

Do not use: tap water, water from a softener, bottled spring water or mineral water. They all carry dissolved minerals. A carnivorous plant's roots are made for nearly pure bog water and can't handle them. The minerals build up in the soil a little more with every watering, and the plant goes downhill slowly enough that you won't connect the two until it's too late. That's what happened to my flytrap when I was a kid.

How: I use the tray method for everything in pots. Set the pot in a saucer or tray and keep about an inch of water in it during the growing season, so the soil stays wet from the bottom up like a bog. Let the tray go nearly dry every so often before you refill it, so the roots get some air. In the winter rest, keep the soil damp but don't stand the pots in water.

Collecting rain: a barrel under a gutter, or just a few clean buckets out in a summer storm. In Wilmington in the summer, you'll have plenty.

More than you think. These are plants of open, sunny places.

• Outdoors in full sun is best for flytraps and pitcher plants, six hours of direct sun a day or more. That's where they get their best red color and their strongest traps.
• A sunny windowsill, facing south, is the least they'll accept indoors, and for flytraps it often isn't quite enough. Sundews and butterworts do fine on a bright sill.
• Fluorescent lights work well for the small ones. I use a plain four-foot shop light with two tubes, hung a few inches above the plants, on a timer for about 14 hours a day. That's where my sundews and butterworts live in the spare room.
• Signs of too little light: long, floppy, pale green leaves, no red in the traps, and a plant that slowly shrinks.

Soil: one part sphagnum peat moss to one part perlite or clean washed sand. Read the peat bag and make sure nothing has been added to it. Never regular potting soil, which almost always has fertilizer, and often lime. Never garden dirt.

Pots: plastic or glazed. Unglazed clay pots dry out fast and can hold minerals. Give flytraps a pot at least four inches deep, since they like a long root run, and give pitcher plants a deep one too.

Repotting: every year or two, in early spring, just before they wake up. Fresh peat makes a happy plant.

• Outdoors, they feed themselves. You don't need to do a thing. My bog pitcher plants catch so many bugs in August that some of the pitchers fall over from the weight.
• Indoors, a live insect once in a while is plenty: a fly, a small cricket from the pet store, a spider. A trap or two a month on a flytrap is enough.
• It has to be alive. A flytrap needs the bug to keep moving inside the closed trap, or it won't seal and digest. If you're feeding a dead bug, you'll have to gently tickle the closed trap from outside for a while to fool it. I don't bother.
• Size matters. Pick something no bigger than about a third of the trap, so the trap can seal all the way around. A too-big meal sticks out, rots, and takes the trap with it.
• Never hamburger, cheese, lunch meat or anything else from your kitchen. It rots in the trap. I learned this when I was eight.
• No fertilizer. Not on the soil, not in the water. I'll say this until I'm blue in the face.

This is the one people miss. Flytraps, pitcher plants and some sundews come from places with real seasons, and they need a cool winter rest of about three months, roughly November through February. As the days get short and cool, the plant slows down, makes smaller leaves, lets the big summer traps die back, and sits there looking dead. It isn't dead. It's resting. In the spring it wakes up and grows like crazy.

• What they want: cool, mostly between about 35 and 50 degrees, some light, and damp soil. A light frost doesn't hurt them.
• Here in Wilmington, they just stay outside, in the bog and on the porch. If a hard freeze is coming, I cover the bog with pine straw and move the pots up against the house.
• Farther north, people use an unheated garage or porch with a window, a cold frame, or a cold windowsill in an unheated room. Some growers dig the plants up, clean them, wrap them in damp sphagnum in a plastic bag and keep them in the refrigerator for the winter. I've never had to, but I know folks who swear by it.
• What not to do: keep a flytrap on a warm kitchen windowsill all year. It will look fine for a while and then wear itself out.
• In late winter, snip off the dead leaves and the old pitchers, so the new growth gets the light.

The tropical kinds (Cape sundews, Mexican butterworts and tropical pitcher plants) don't need a cold rest. See the chart.

In spring a flytrap sends up a tall stalk with a cluster of little white flowers on top, well above the traps, so the bees that pollinate it don't get eaten by it. Smart plant. Flowering takes a lot out of a flytrap, so many growers cut the stalk off when it's a few inches tall, unless they want seed. I let one or two of my big ones flower every year, hand-pollinate them with a small paintbrush, and grow the seed. The tray of seedlings in my collection came from that.

Pitcher plant flowers are something else: big, nodding, strange-looking flowers on long stems in early spring, before the pitchers come up. Yellow on S. flava, dark red on S. purpurea. Worth growing for the flowers alone.

Questions I didn't answer? Write me at [email protected]. Tell me what kind of plant, where it sits, what water you use, and what it looks like, and I'll do my best. I can't promise I'll know. I can promise I'll be interested.

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