Plant care guide
Venus Flytrap Dormancy: Temperature, Length and Care
Updated
What does a Venus flytrap need during dormancy?
A Venus flytrap is a temperate plant that rests each winter. Shortening days trigger dormancy, leaves blacken and die back, and the rhizome survives underground. NC State Extension recommends at least 10 weeks at 2–10 °C (35–50 °F).
What to do first
Do not throw out a flytrap that blackens in November. Give it a cool, bright spot, keep the mix moist but not waterlogged, and protect it from hard freezes. Resume normal care when spring growth starts.
If your Venus flytrap turned black and shrivelled in late autumn, it has probably not died. NC State’s New Hanover County Center describes this as the plant entering dormancy. It is the same rest the species takes every winter in the longleaf pine savannas of southeastern North Carolina.
What Dormancy Looks Like
The above-ground parts die back, but the plant survives underground in its rhizome. NC State describes the rhizome as a bulb-like structure that stores energy until spring. During the rest it builds up starch reserves that fuel spring growth.
Expect:
- Leaves and traps blackening or shrivelling from about November.
- Little or no new growth through winter.
- Fresh leaves from the centre as days lengthen in spring.
A plant that is black above ground in midwinter is not proof of death. Wait for spring before deciding.
What Triggers It
NC State names two cues. The primary one is day length: as autumn days shorten, the plant shifts from growth to storage. Cooler temperatures reinforce the signal. Missouri Botanical Garden gives a similar picture: dormancy usually begins in autumn as temperatures fall below 10 °C (50 °F) and days shorten.
How Cold and How Long
| Guidance | Temperature | Length | Source |
|---|---|---|---|
| Recommended rest | 2–10 °C (35–50 °F) | At least 10 weeks; three to five months is fine | NC State New Hanover |
| Indoor overwintering | 4–10 °C (40–50 °F) in a sunny, cool window | Through winter | Missouri Botanical Garden |
| Terrarium or refrigerator rest | Below about 7 °C (45 °F) | At least 45 days | Clemson Extension |
| UK windowsill guidance | Cool, but above 10 °C (50 °F); not a warm room | Over winter | RHS |
The figures differ, but every source agrees on one point: a flytrap should not spend winter in a warm living room. The RHS lists warm winter conditions among the things the plant dislikes.
Outdoors, NC State advises protecting plants from hard freezes below about −7 °C (20 °F). NC State’s plant profile gives winter hardiness in USDA zones 7 to 10, and down to zones 5 and 6 with winter protection.
Ways to Give a Dormancy
Outdoors or an unheated space. Let the plant rest where it is. NC State says to keep the soil moist but not waterlogged. Clemson Cooperative Extension suggests a garage, basement or covered patio, and says the plants do not need supplemental light while dormant.
Cool windowsill. Missouri Botanical Garden suggests a sunny but cool south-facing window at 4–10 °C (40–50 °F). An unheated room that stays in that range works the same way.
Refrigerator. Clemson describes this as a fallback when no cool space exists:
- Clean tools with 70% isopropyl alcohol.
- Lift the plant and trim tall leaves.
- Wrap the roots in damp sphagnum if the growing mix comes away.
- Seal in a lidded plastic container. Light is not needed.
- Refrigerate for at least 45 days. Never use the freezer.
Can You Skip Dormancy?
NC State’s New Hanover article says plants grown under strong grow lights can skip it. That means roughly 15,000 to 25,000 lux of LED light for about 14 hours daily, plus regular feeding. A dim windowsill does not qualify.
The same article warns that skipping dormancy repeatedly leads to decline. Plants become less vigorous and more prone to disease. Clemson states that temperate carnivorous plants deteriorate over time without dormancy.
If your plant lives on a windowsill, NC State’s advice is to let it rest and be consistent. Do not switch it between grow lights and natural winter light.
Waking the Plant in Spring
Return the plant to full light and normal temperatures as days lengthen. Keep using rainwater or distilled water and keep the mix moist. New leaves from the centre confirm the rhizome came through.
More care topics are on our Venus flytrap hub.
Related guides
Other venus flytrap problems we cover: traps not closing, light requirements, distilled water requirement.
References
- N.C. Cooperative Extension, New Hanover County Center: Venus Flytrap Dormancy (2026)
- NC State Extension Gardener Plant Toolbox: Dionaea muscipula
- Clemson Cooperative Extension HGIC: Creating an Indoor Carnivorous Wetland Terrarium (2026)
- Missouri Botanical Garden Plant Finder: Dionaea muscipula
- RHS: Venus fly trap plant guide
How this guide was put together: NC State Extension, Clemson Cooperative Extension, Missouri Botanical Garden and RHS guidance.