Green Iguana (Iguana iguana) Care Sheet
The Green Iguana is a large, highly intelligent arboreal lizard native to tropical regions of Central and South America and parts of the Caribbean. Despite being one of the most recognisable reptiles in captivity, it is also one of the most frequently underestimated.
Juveniles are often sold at a relatively small size, but adults can become exceptionally large and powerful. Mature Green Iguanas require very substantial accommodation, intense lighting, strong UVB, carefully controlled heating and a nutritionally appropriate herbivorous diet.
With correct husbandry they can be impressive and engaging reptiles, but their size, strength and long lifespan make them a significant long-term commitment.
Quick Facts
Scientific name: Iguana iguana
Common name: Green Iguana / Common Green Iguana
Family: Iguanidae
Origin: Central America, South America and parts of the Caribbean
Adult size: Commonly approximately 120–180 cm (4–6 ft) total length
Lifespan: Approximately 15–20+ years with appropriate care
Activity: Diurnal
Lifestyle: Arboreal
Diet: Herbivorous
Temperament: Intelligent and variable; adults can be powerful and territorial
Experience level: Advanced
Natural History
Green Iguanas inhabit tropical and subtropical environments including:
- Rainforest
- River margins
- Forest edges
- Mangroves
- Woodland
- Vegetated areas close to water
They are excellent climbers and spend considerable periods above ground in trees and dense vegetation.
Green Iguanas are also capable swimmers and may enter water when escaping predators.
Their natural lifestyle involves extensive exposure to:
- Sunlight
- Heat
- Vegetation
- Climbing opportunities
- Seasonal environmental changes
These factors should be considered when designing captive accommodation.
Adult Size
Green Iguanas become very large reptiles.
Adult males can approach or occasionally exceed approximately 1.5 metres in total length, with much of that length consisting of the tail.
Males generally develop:
- Larger heads
- More prominent jowls
- Larger femoral pores
- More substantial dorsal spines
- Heavier bodies
The small juvenile commonly encountered in captivity therefore bears little resemblance in size or strength to a mature adult.
Adult dimensions must be considered before acquiring a juvenile.
Enclosure
Adult Green Iguanas require extremely substantial accommodation.
A suitable adult enclosure should be approximately:
240 × 120 × 180 cm (8 × 4 × 6 ft)
as a practical minimum starting point, with larger accommodation strongly encouraged.
Many adults are best maintained in purpose-built room-sized enclosures.
The enclosure should provide:
- Extensive climbing structures
- Large elevated shelves
- Multiple sturdy branches
- Broad basking areas
- Visual barriers
- Secure retreats
- Feeding platforms
- Fresh water
- Strong ventilation
Vertical space is particularly important.
An adult Green Iguana should be able to climb, turn, stretch and move normally throughout its enclosure.
Juvenile Enclosures
Juveniles can initially be maintained in smaller accommodation, but the enclosure must still provide:
- Appropriate UVB
- Correct basking temperatures
- Climbing opportunities
- Dense cover
- Multiple thermal zones
Juvenile accommodation should not be viewed as a permanent solution.
Growth can be rapid under appropriate conditions.
Planning and construction of adult accommodation should begin well before the animal reaches adult size.
Climbing
Green Iguanas are strongly arboreal.
Provide numerous sturdy climbing structures including:
- Thick branches
- Large cork structures
- Shelves
- Platforms
- Elevated basking areas
All structures must be capable of safely supporting the full weight of an adult.
Branches should be arranged at different:
- Heights
- Angles
- Temperatures
- Levels of exposure
Smooth or unstable climbing structures should be avoided.
Enclosure Security
Adult Green Iguanas are strong animals.
The enclosure requires:
- Secure doors
- Strong hinges
- Reliable locks
- Protected ventilation
- Secure lighting equipment
- Protected electrical cables
Lightweight furnishings can easily be moved or overturned.
Any internally mounted heating equipment accessible to the iguana must be appropriately guarded.
Temperature & Heating
Green Iguanas require a strong daytime thermal gradient.
Suitable temperatures are approximately:
Basking surface: 38–42°C
Warm ambient area: approximately 28–32°C
Cooler area: approximately 24–27°C
Night: approximately 20–24°C
The animal must always be able to move away from the basking area.
Large adult enclosures may require multiple heat sources to create an appropriately broad basking zone.
Basking
A mature Green Iguana requires a broad basking area, not a single tiny hotspot.
Several appropriately positioned halogen lamps can be used to warm a large basking platform evenly.
Surface temperatures should be measured with an infrared thermometer.
Ambient temperatures should be monitored using reliable digital thermometers.
Do not estimate temperature by touch.
All heating equipment must be appropriately controlled and safely installed.
UVB
Strong UVB provision is essential.
Green Iguanas are highly heliothermic reptiles naturally exposed to substantial levels of sunlight.
A high-quality linear UVB system should be provided.
A useful basking target is approximately:
UVI 3–6
with shaded areas where UV exposure falls substantially lower.
The animal must be able to regulate its own exposure.
Actual UV intensity depends upon:
- Lamp output
- Reflector
- Distance
- Mesh
- Basking position
- Enclosure design
Follow manufacturer recommendations and ideally verify exposure using an appropriate UV meter.
UVB lamps should be replaced according to manufacturer guidance.
Visible Light
Very bright visible lighting is important for this strongly diurnal species.
Daylight-spectrum LED lighting can be used alongside heat and UVB.
A Green Iguana enclosure should appear genuinely bright during daytime while still containing shaded retreats.
Provide approximately:
12–14 hours of light per day
with seasonal variation where appropriate.
The enclosure should become genuinely dark at night.
Avoid red, blue or purple nighttime bulbs.
Humidity
Green Iguanas originate from relatively humid tropical environments.
A useful general range is approximately:
60–80% relative humidity
with natural fluctuations throughout the day.
Humidity can be supported through:
- Misting
- Live plants
- Appropriate substrate
- Large water containers
- Controlled environmental humidity
High humidity must be accompanied by good ventilation.
A permanently stagnant, saturated enclosure is inappropriate.
Misting
Regular misting can provide:
- Temporary humidity increases
- Drinking droplets
- Support during shedding
Automatic misting systems can be particularly useful in large enclosures.
The enclosure should still be allowed to experience appropriate drying between misting periods.
Only clean, reptile-safe water should be used.
Water
Fresh drinking water should be available at all times.
Provide a large, stable water container.
Some Green Iguanas may enter their water container.
The water should therefore be:
- Changed regularly
- Replaced immediately when contaminated
- Maintained in a thoroughly cleaned container
Large iguanas can rapidly contaminate water.
Substrate
Suitable substrate choices depend heavily upon enclosure design.
Options can include:
- Reptile-safe soil
- Soil-based naturalistic mixtures
- Cypress-type reptile substrate
- Bioactive substrate systems
Large adult enclosures may also incorporate easily cleaned solid areas alongside naturalistic sections.
Avoid:
- Calcium sand
- Cedar
- Pine
- Crushed walnut shell
- Artificially scented substrate
- Loose materials that create an unnecessary ingestion risk
Substrate should be maintained hygienically.
Furnishing & Enrichment
Green Iguanas are intelligent, active reptiles that benefit substantially from environmental complexity.
Suitable enrichment includes:
- Multiple climbing routes
- Large branches
- Elevated platforms
- Visual barriers
- Safe vegetation
- Different textures
- Feeding enrichment
- Multiple basking positions
Food can be presented in different areas to encourage movement and natural foraging behaviour.
The enclosure should encourage:
- Climbing
- Exploring
- Basking
- Foraging
- Exercise
A large but completely empty enclosure does not provide appropriate behavioural opportunities.
Diet
Green Iguanas are herbivorous.
Their captive diet should be based predominantly upon a varied selection of nutritious leafy greens and other appropriate plant material.
Animal protein should not form a routine part of the diet.
Suitable staple greens can include:
- Dandelion greens
- Collard greens
- Mustard greens
- Turnip greens
- Endive
- Escarole
- Rocket
- Appropriate edible weeds
- Other calcium-rich leafy vegetation
Dietary variety is extremely important.
Vegetables
Suitable vegetables can be incorporated into the diet.
Examples include:
- Squash
- Courgette
- Green beans
- Bell pepper
- Grated carrot in moderation
- Parsnip
- Other appropriate vegetables
Vegetables should complement rather than replace the leafy-green foundation of the diet.
Foods should be chopped or prepared appropriately for the size of the animal.
Fruit
Fruit should form only a small proportion of the overall diet.
Suitable occasional fruits can include:
- Papaya
- Mango
- Berries
- Melon
- Fig
Fruit is generally higher in sugar and lower in the mineral balance required from staple foods.
It should therefore be regarded as dietary variety rather than a major component.
Foods to Limit or Avoid
Avoid making nutritionally poor foods the foundation of the diet.
Foods such as iceberg lettuce provide little nutritional value compared with better leafy greens.
Spinach and some other plants contain compounds that can interfere with mineral utilisation when fed excessively and should not dominate the diet.
Avoid:
- Dog food
- Cat food
- Meat
- Rodents
- Eggs
- Insects as routine food
- Dairy products
- Processed human food
Green Iguanas do not require routine animal protein.
Calcium-to-Phosphorus Balance
Correct dietary mineral balance is extremely important.
The overall diet should favour calcium-rich foods and avoid excessive phosphorus.
Calcium metabolism also depends upon:
- Strong UVB exposure
- Appropriate vitamin D3 metabolism
- Correct basking temperatures
- Overall dietary quality
Simply adding calcium powder cannot compensate for a fundamentally poor diet or inadequate UVB.
Calcium & Supplementation
A suitable calcium supplement can be used according to:
- Age
- Diet
- UVB provision
- Reproductive status
A suitable reptile multivitamin can also be provided periodically.
Growing juveniles and reproductive females require particularly careful nutritional management.
Avoid excessive supplementation.
The objective is to provide a nutritionally balanced diet rather than relying upon powders to correct inappropriate food choices.
Feeding Frequency
Juvenile Green Iguanas should generally have access to appropriate fresh food daily.
Adults should also normally receive fresh plant material daily, with quantity adjusted according to:
- Body condition
- Activity
- Age
- Reproductive status
Remove spoiled food promptly.
Fresh drinking water should always remain available.
Feeding Presentation
Green Iguanas naturally feed amongst vegetation.
Food can be presented:
- In elevated feeding bowls
- On platforms
- At different enclosure levels
- Through safe browsing opportunities
Elevated feeding areas can encourage natural arboreal behaviour.
Food bowls should be stable enough that a large iguana cannot easily overturn them.
Handling
Green Iguanas vary enormously in temperament.
Some captive-bred individuals become relatively tolerant of human interaction, while others remain defensive.
Handling should be based upon calm conditioning rather than forced restraint.
When handling:
- Approach calmly
- Support the entire body
- Support the hindquarters
- Control the animal without excessive pressure
- Never grab the tail
Young iguanas can be extremely fast.
Adults are considerably stronger than their appearance may suggest.
Defensive Behaviour
A defensive Green Iguana may:
- Inflate the body
- Extend the dewlap
- Bob the head
- Turn sideways
- Open the mouth
- Tail-whip
- Bite
- Attempt to flee
These warning behaviours should be respected.
Repeatedly forcing interaction with a defensive animal can increase stress and aggression.
Bites
Adult Green Iguanas possess powerful jaws and sharp teeth.
A serious bite can cause substantial injury.
Reduce bite risk by:
- Learning the animal’s body language
- Avoiding unnecessary restraint
- Keeping hands away from the mouth
- Using appropriate handling techniques
Significant bites should receive appropriate medical attention.
Tail Whipping
The long muscular tail is an effective defensive weapon.
Large adults can deliver powerful tail strikes.
Never grab or restrain an iguana by its tail.
Tail injuries can occur through inappropriate restraint or enclosure accidents.
Claws
Green Iguanas possess long, sharp claws adapted for climbing.
Even a calm animal can accidentally scratch a handler while attempting to obtain a secure grip.
Providing appropriate climbing surfaces can help maintain normal claw wear.
Claw trimming may occasionally be necessary and should be performed carefully.
Shedding
Green Iguanas shed their skin in sections.
Pay particular attention to:
- Toes
- Tail
- Dorsal spines
- Limbs
Appropriate hydration and humidity support normal shedding.
Textured branches and other surfaces allow natural rubbing.
Do not forcibly peel skin that is not ready to detach.
Persistent retained shed around toes or the tail can restrict circulation.
Housing
Green Iguanas do not require companionship.
Individual housing is entirely appropriate.
Adult males can be highly territorial and should not normally be housed together.
Even male/female or female/female combinations require:
- Very large accommodation
- Multiple basking positions
- Multiple feeding areas
- Visual barriers
- Careful behavioural monitoring
Separate animals if persistent aggression, intimidation or resource guarding occurs.
Seasonal & Reproductive Behaviour
Mature Green Iguanas can display substantial behavioural changes during reproductive periods.
Adult males may become:
- More territorial
- More defensive
- More restless
- More prone to biting or tail-whipping
Keepers should understand that even a normally calm adult may behave differently during hormonal periods.
Handling and enclosure management may need to be adjusted accordingly.
Females & Egg Laying
Female Green Iguanas can produce eggs even without mating.
Mature females therefore require appropriate consideration for reproductive health.
A female preparing to lay may show:
- Increased digging
- Restlessness
- Reduced appetite
- Changes in body shape
- Searching behaviour
Suitable nesting opportunities may be required.
Difficulty laying eggs can become a serious veterinary emergency.
Health
Potential health concerns include:
- Metabolic bone disease
- Nutritional deficiencies
- Obesity
- Dehydration
- Burns
- Retained shed
- Parasites
- Respiratory disease
- Mouth infections
- Kidney disease
- Reproductive complications
- Trauma
Warning signs include:
- Weakness
- Tremors
- Swollen limbs
- Abnormal jaw shape
- Difficulty climbing
- Significant weight loss
- Persistent refusal to feed
- Mouth swelling
- Nasal discharge
- Laboured breathing
- Significant behavioural changes
Persistent or serious symptoms require assessment by a suitably experienced reptile/exotic veterinarian.
Metabolic Bone Disease
Metabolic bone disease is one of the most important preventable health problems associated with poorly maintained Green Iguanas.
Risk factors include:
- Inadequate UVB
- Calcium-poor diet
- Poor calcium-to-phosphorus balance
- Inappropriate supplementation
- Incorrect temperatures
Possible signs include:
- Tremors
- Weakness
- Soft or swollen jaw
- Limb deformities
- Difficulty climbing
- Fractures
An animal showing possible signs requires veterinary assessment.
Correct husbandry is fundamental to prevention.
Quarantine
New Green Iguanas should undergo quarantine away from established reptiles.
During quarantine:
- Record body weight
- Monitor feeding
- Examine faeces
- Check skin
- Monitor breathing
- Observe behaviour
- Check for external parasites
- Maintain separate equipment where practical
Veterinary faecal testing may be appropriate where an animal’s previous history is uncertain.
Captive-bred animals from reliable sources should be strongly preferred.
Sexing
Sexual differences become increasingly obvious as Green Iguanas mature.
Adult males generally develop:
- Larger heads
- More substantial jowls
- Larger femoral pores
- More prominent dorsal spines
- Broader tail bases
- More pronounced dewlaps
Females generally remain less heavily built.
Juveniles can be considerably more difficult to sex reliably.
Breeding
Green Iguanas are egg-laying reptiles.
Breeding should only be attempted with healthy mature animals and appropriate facilities.
Breeding requires knowledge of:
- Sexing
- Sexual maturity
- Courtship
- Territorial behaviour
- Female body condition
- Nesting
- Egg incubation
- Hatchling husbandry
Females require excellent calcium reserves and access to suitable nesting conditions.
Breeding should never be undertaken without a realistic plan for housing and placing the resulting offspring.
Eggs & Incubation
Females deposit eggs in excavated nests.
Captive nesting facilities must allow the female to dig and select an appropriate laying site.
When artificially incubated, eggs require carefully controlled:
- Temperature
- Moisture
- Gas exchange
Eggs should not be unnecessarily rotated once embryonic development is established.
Breeders should research current species-specific incubation practices before attempting reproduction.
Hatchlings
Hatchlings require appropriately scaled adult conditions including:
- Strong UVB
- Correct basking temperatures
- Bright visible lighting
- Numerous climbing structures
- Dense cover
- Fresh water
- Appropriate herbivorous nutrition
Young Green Iguanas can grow rapidly.
The objective should be steady healthy development rather than maximum growth.
Particular attention should be paid to calcium nutrition and UVB provision.
Conservation & Invasive Populations
Green Iguanas are native to the tropical Americas but have also become established outside their natural range.
Introduced populations occur in several regions where escaped or released animals have successfully reproduced.
This highlights the importance of secure captive management.
A captive Green Iguana should never be deliberately released into the wild.
Legal Considerations
Legal requirements affecting Green Iguanas can vary between jurisdictions.
Before acquiring, breeding, selling, transporting, importing or exporting an animal:
- Check current national legislation
- Check applicable wildlife-trade regulations
- Retain relevant documentation
- Confirm any local restrictions concerning invasive species
Regulations can change, so current official guidance should always be consulted.
Responsible Ownership
Green Iguanas can live for 15–20 years or longer with appropriate care.
Before acquiring one, consider:
- Adult size approaching 1.5 metres or more
- Room-sized enclosure requirements
- Strong UVB
- High basking temperatures
- Very bright visible lighting
- Daily fresh food
- Powerful jaws
- Sharp claws
- Tail-whipping ability
- Specialist veterinary care
- Long-term financial commitment
The inexpensive purchase price of a juvenile does not reflect the cost or complexity of maintaining a healthy adult.
Green Iguanas should only be acquired when suitable adult accommodation can realistically be provided.
Captive-bred animals should be strongly preferred.
Never release a captive Green Iguana into the wild.
Summary
The Green Iguana is an impressive, intelligent and highly specialised arboreal herbivore whose husbandry requirements are frequently underestimated.
Successful long-term care depends upon providing an exceptionally spacious and vertically complex enclosure, strong UVB, intense visible lighting, a broad high-temperature basking area, appropriate humidity and a varied calcium-rich herbivorous diet based primarily upon leafy vegetation.
Their considerable adult size, strength, intelligence and potential for territorial behaviour mean they require significantly more commitment than many commonly maintained reptiles.
When their environmental, nutritional and behavioural requirements are properly met, Iguana iguana can be an exceptionally impressive reptile to maintain.
IMPORTANT INFORMATION
This care sheet provides general husbandry guidance and does not replace species-specific research or veterinary advice. Individual requirements may vary.
If you have concerns about an animal’s health or care, consult a suitably experienced exotic or reptile veterinarian.
Information correct at the date of publication.
reptilecommunity.com | Revised: August 2026