Lizards
Emerald tree monitor care guide
Varanus prasinus
A slender, shy arboreal monitor (about 3 ft). Advanced; often kept in pairs.
Arboreal — vertical height first
New to reptiles? Check your keeper level first →Emerald tree monitor enclosure size
Arboreal — vertical height first. An adult emerald tree monitor should live in at least 36" L × 24" W × 72" H; we build toward 48" L × 36" W × 72" H (4 × 3 × 6 ft, roughly 12 sq ft of floor and about a 539-gallon glass equivalent).
- Hatchling / baby
- 18" L × 12" W × 18" H recommended · min 12" L × 12" W × 18" H
- Juvenile
- 30" L × 24" W × 24" H recommended · min 24" L × 18" W × 24" H
- Adult
- 48" L × 36" W × 72" H recommended · min 36" L × 24" W × 72" H
Temperature and heating
Overhead heat (halogen, deep heat projector or radiant panel) on a thermostat, creating a warm-to-cool gradient.
- Basking / warm surface
- 120°F basking surface
- Warm side (ambient)
- 88–92°F
- Cool side (ambient)
- 78–82°F
- Night
- No lower than 72°F
Lighting and UVB
UVB: Strong UVB required (T5 HO 10–12% across most of the enclosure). Run lights on a 12 hours on, 12 hours off photoperiod, on a timer, and replace UVB bulbs on the manufacturer's schedule even while they still emit visible light.
Humidity
Target 70–80%. Daily misting, live plants and a water bowl.
Substrate and depth
Soil/coco or bioactive. Depth: 4–6 in.
Diet and feeding
Mostly insects (roaches, superworms, crickets), dusted, with occasional pinkies.
Enclosure tips and furnishing
- Hides on both the warm and cool sides
- Clean water available at all times
- Branches and foliage for climbing and cover
Build list
- Enclosure at adult size — Buy for the adult footprint to avoid repeated upgrades.
- Digital thermostat — Every heat source must run through a thermostat — unregulated heat burns animals.
- Two digital probe thermometers + hygrometer — Read the warm side, cool side and humidity directly.
Emerald tree monitor FAQ
How big should an adult Emerald tree monitor enclosure be?
At least 36" L × 24" W × 72" H, and we recommend building to 48" L × 36" W × 72" H — about 4 × 3 × 6 ft, or a 539-gallon glass equivalent. Arboreal — vertical height first.
What temperatures does an Emerald tree monitor need?
Basking or warm surface 120°F basking surface, warm side 88–92°F, cool side 78–82°F, night No lower than 72°F. Overhead heat (halogen, deep heat projector or radiant panel) on a thermostat, creating a warm-to-cool gradient.
Does an Emerald tree monitor need UVB?
Strong UVB required (T5 HO 10–12% across most of the enclosure). Photoperiod: 12 hours on, 12 hours off.
What humidity does an Emerald tree monitor need?
70–80%. Daily misting, live plants and a water bowl.
What substrate is best for an Emerald tree monitor?
Soil/coco or bioactive, at a depth of 4–6 in.
How big does an Emerald tree monitor enclosure need to be for a hatchling?
Hatchling / baby: 18" L × 12" W × 18" H recommended, minimum 12" L × 12" W × 18" H. Scale up to the adult footprint as the animal grows.
Sources
Put this guide to work
Apply these targets to your own emerald tree monitor record, then log feedings, sheds and weights against them.