Green Iguana Care: Feeding, Heating, and Housing Basics

Green iguanas are among the most recognizable reptiles kept as pets, known for their bright green scales, spiny crests, and calm-looking demeanor. That calm look can be misleading. A green iguana is a large, long-lived, tropical animal with very specific needs for heat, light, space, and plant-based food. Meeting those needs correctly is the difference between a healthy iguana that lives well over a decade and one that develops preventable health problems within a year or two.

This guide covers the three pillars of green iguana care — feeding, heating, and housing — in plain terms, plus handling, cleaning, and the health signs worth watching.

Quick Facts About Green Iguanas

• Size: Adults commonly reach 4 to 6 feet including the tail.
• Lifespan: 10 to 20 years with good care.
• Diet: Plant-based as adults. They eat vegetation, not meat.
• Temperature needs: A hot basking zone plus a warm overall enclosure.
• UVB light: Essential for processing calcium.

Because they grow large and live long, iguanas are a long-term commitment rather than a starter pet.

Housing Basics

Enclosure Size

A young iguana can start in a smaller cage, but it will outgrow that quickly. Plan for adult size from the beginning so you do not have to rebuild the setup in a year.

A reasonable minimum for an adult is about 6 feet tall, 4 feet wide, and 2 to 3 feet deep. Taller is better, since iguanas are arboreal and spend most of their time off the ground. Many keepers build custom enclosures to hit these dimensions.

Type of Enclosure

Fully screened cages allow good airflow but struggle to hold heat and humidity. Enclosed cages with vents hold warmth and moisture far better, which suits a tropical species. A wooden or glass enclosure with a screen top and lower front vents is a common middle ground.

What Goes Inside

• Basking branch or shelf: sturdy and positioned at different heights so the iguana can choose its temperature.
• Multiple perches: wide enough to grip comfortably. Use untreated branches with no pesticide residue.
• Hide area: a retreat where the animal feels secure.
• Substrate: simple options work best — plain paper, tile, coconut coir, or cypress mulch. Avoid sand and aromatic wood shavings.
• Large shallow water bowl: big enough for soaking, refreshed daily.
• Heavy food dish: one that will not tip over.

Heating and Lighting

Temperature Zones

Iguanas need a heat gradient, meaning a hot basking area and a cooler side so they can regulate their own body temperature.

• Basking spot: about 95 to 100 degrees Fahrenheit (35 to 38 Celsius)
• Warm side: about 85 to 90 degrees Fahrenheit (29 to 32 Celsius)
• Cool side: about 75 to 80 degrees Fahrenheit (24 to 27 Celsius)
• Nighttime: no lower than about 75 degrees Fahrenheit (24 Celsius)

Place thermometers at both ends of the enclosure and use a thermostat to control the heat source. Guessing at temperatures is one of the most common causes of illness.

Heat Sources

Overhead bulbs work well during the day. For night heat, use a source that produces warmth without light so the iguana can still sleep on a natural dark cycle. Avoid heated rocks, which can burn a reptile that senses heat from above rather than through its belly.

UVB Lighting

UVB light allows an iguana’s skin to produce vitamin D3, which is needed to absorb calcium. Without adequate UVB, bones soften and deform — a condition called metabolic bone disease. Replace UVB bulbs on the schedule the packaging recommends, often every 6 to 12 months, even if the bulb still glows. Aim for roughly 10 to 12 hours of light and 12 hours of darkness each day.

Humidity

Green iguanas come from humid tropical environments. Target 60 to 80 percent relative humidity, measured with a hygrometer. Mist the enclosure once or twice daily, and provide a damp area or moist hide. Good humidity supports healthy shedding and hydration.

Feeding

What to Feed

Adult green iguanas are herbivores. A practical daily mix is roughly 40 to 45 percent dark leafy greens, 40 to 45 percent other vegetables, and 10 to 15 percent fruit.

• Staple greens: collard greens, mustard greens, turnip greens, dandelion greens, escarole, endive, watercress, arugula, bok choy.
• Other vegetables: winter squash, bell pepper, green beans, snap peas, zucchini, carrots, cooked sweet potato, okra.
• Fruit in small amounts: berries, melon, papaya, mango, fig, kiwi.

Chop everything into small pieces, mix it together, and serve fresh. Remove leftovers after a few hours so they do not spoil or grow mold.

Foods to Avoid

• Iceberg lettuce, which is mostly water with little nutrition.
• Animal protein such as meat, dog or cat food, cheese, or eggs. Excess protein is hard on an iguana’s kidneys.
• High-oxalate foods in large amounts, including spinach, rhubarb, beet greens, and chard. These bind calcium so it cannot be absorbed.
• Avocado, which is toxic to many animals.
• Processed human foods, sugary items, and anything with added salt or seasoning.

Calcium and Supplements

Lightly dust food with a calcium powder that does not contain phosphorus. This matters most for growing juveniles and for females producing eggs. A general reptile multivitamin once or twice a month is often enough. Do not overdo it — certain vitamins build up in the body and can cause problems in large doses, so follow the label directions.

Feeding Schedule

• Juveniles: once or twice a day in small amounts.
• Adults: once daily or every other day.

Provide fresh drinking water every day, and keep the water bowl clean.

Handling and Socialization

Young iguanas are often nervous and fast. Move slowly, support the front and hindquarters when lifting, and let the animal walk onto your hand rather than snatching it up. Never grab the tail — iguanas can shed part of it as a defense mechanism and it may not grow back normally. Keep early handling sessions short and increase them gradually as the animal settles. Wash your hands before and after every interaction.

Cleaning and Hygiene

Spot-clean droppings every day, change the water daily, and do a full cleaning about once a month. Scrub surfaces, replace the substrate, disinfect with a reptile-safe cleaner, and rinse everything thoroughly before putting it back. Reptiles can carry bacteria such as salmonella, so wash your hands after contact and avoid cleaning enclosure items in the kitchen sink.

Signs of a Healthy vs. Unhealthy Iguana

A healthy iguana has bright eyes, a firm jaw, smooth skin, a steady appetite, and solid droppings. It moves around and basks normally. Warning signs that deserve a veterinarian experienced with reptiles include:

• Loss of appetite or noticeable weight loss
• Lethargy, constant hiding, or unwillingness to move
• A soft, rubbery, or swollen jaw, or trouble climbing — possible metabolic bone disease
• Wheezing, mucus around the nose or mouth, or open-mouth breathing
• Sunken eyes or wrinkled skin, which suggest dehydration
• Discolored, blistered, or crusted skin, often from burns or infection

Common Mistakes to Avoid

1. Buying the animal before having an adult-sized enclosure ready.
2. Using an old UVB bulb or skipping UVB entirely.
3. Feeding animal protein or too much fruit.
4. Using heated rocks as a heat source.
5. Letting the enclosure run too cool or too dry.
6. Assuming a quiet, inactive iguana is simply calm, when it may be cold or sick.

The Bottom Line

Green iguana care comes down to three things: a large, secure enclosure; correct heat and UVB lighting; and a plant-based diet supported with calcium. When those are in place, most common health problems stay away. Check temperature and humidity daily, refresh food and water, and watch your iguana’s behavior closely — any change in appetite or activity is worth investigating.

If you are still deciding whether an iguana fits your life, weigh its adult size, long lifespan, and daily upkeep against your available space and schedule before committing. For more plain-language guides on pet care, home upkeep, and everyday how-tos, explore the other articles on this site.