Venus flytrap care guide

The Venus flytrap is a carnivorous plant with leaves that snap shut on insects. It grows wild in one small area of the Carolinas, in sunny, boggy, poor soil. To keep one alive indoors, copy that: full sun, pure water, peat, no fertilizer, and a cold winter rest.

Light

Flytraps need direct sun, at least four hours a day and more if you can. A south or west window is best. A strong grow light works well.

In low light, the traps grow long, floppy, and green, and stop closing well. Bright red inside the traps is a sign of good light.

Water

Use only distilled water, rainwater, or reverse osmosis water. Tap water and bottled mineral water carry minerals that build up and kill the roots.

Keep the soil wet at all times. The easiest way is the tray method: set the pot in a saucer with 1 to 2 cm (½ to 1 in) of water and refill it as it drops. Let it dry a little more in winter.

Soil and potting

Use a mix of sphagnum peat moss and perlite, about half and half. Never use potting soil, compost, or anything with fertilizer added.

Use a plastic or glazed pot with drainage holes. Repot every year or two in late winter, before growth starts.

Humidity and temperature

Average room air is fine. Flytraps like warm summers, and they can spend summer outside in full sun.

Feeding

Never use fertilizer. It burns the roots.

A flytrap outside catches its own food. Indoors, it can live on light alone, but a small live insect every few weeks in summer helps. Pick a bug about one third the size of the trap. Do not feed it meat.

Do not set off the traps for fun. Each trap can close only a few times before it dies.

Winter rest

Flytraps need a cold rest of about three to four months each winter, between 2 and 10°C (35 and 50°F). Without it, they weaken and die within a year or two.

In a cold climate, this is easy. In late fall, move it to an unheated garage, cold porch, or cool basement window that stays above freezing. Keep the soil damp, not soggy. Leaves will brown and die back. In early spring, bring it back to a warm, sunny window.

Pruning

Snip off black, dead traps and leaves at the base. Cut flower stalks off when they first appear, unless you want seed. Flowering takes a lot of energy.

Propagation

When you repot in late winter, you may find the plant has split into several clumps. Pull or cut them apart, each with roots, and pot each one.

Problems

What you see	Most likely cause
Traps turn black after closing on food	Normal, or the meal was too big
Many traps turn black	Tap water, fertilizer, or too little light
Long, floppy, green traps	Not enough light
Traps will not close	Weak plant, too little light, or a trap closed too many times
Plant fades after a year or two	No winter rest

Pests

Aphids and spider mites can show up on new growth. Fungus gnats in damp peat get eaten by the traps.

Pet safety

The ASPCA lists the Venus flytrap as non-toxic to cats and dogs. The traps cannot hurt a pet.

Varieties

• The common green form with red trap insides.
• ‘Akai Ryu’, or red dragon, turns red all over in strong sun.
• ‘B52’ grows some of the biggest traps.
• ‘Dentate’ types have short, tooth-like edges instead of long bristles.