Green iguanas (Iguana iguana) are large, diurnal, arboreal lizards native to subtropical and tropical areas of North, South and Central America. They have also been introduced to southern Florida, where they thrive as an invasive species. 

Wild-type green iguanas are generally green in color, but captive breeding has developed alternative colors such as red, blue, and yellow. They have robust, muscular bodies, with a row of spikes down the spine, and a dewlap under the chin. Green iguanas can grow as large as 6’ long and weigh up to 20 lbs.

Juvenile iguanas are easy to find in the pet trade, but that doesn’t mean they’re easy pets. In fact, due to their adult size and temperament, green iguanas are considered advanced-level pet reptiles. Please do not consider an iguana as a pet unless you are prepared to house and feed a very large reptile.

How much space do green iguanas need?

Green iguanas are large, active lizards, so they need an appropriately large enclosure. Baby iguanas can be kept in a smaller, 40-55 gallon tank until they reach 18” long, but at that point they need to be moved to their adult enclosure. The minimum size for a single adult iguana is 12’L x 6’W x 6’H. This size of enclosure may not be readily available for purchase, so you may need to order one custom-made or build your own.

Cohabitation (keeping multiple green iguanas in the same enclosure) is generally not recommended.

Do green iguanas need UVB?

UVB is required for green iguanas to stay healthy. Aside from helping provide a day/night cycle and providing an infinite supply of vitamin D, UVB is also good for the lizard’s overall health. Here are the best UVB bulbs for green iguanas housed in an indoor 12’L x 6’W x 6’H enclosure:

• Arcadia T5 HO Desert 12%, 34”, x2
• Zoo Med Reptisun T5 HO 10.0, 34”, x2

If the UVB is mounted over mesh, place the basking branch so the iguana’s back will be 13-15” below the lamp. If the UVB is mounted inside the enclosure, place the basking branch so the iguana's back will be 17-18” below the lamp. 

You will need two bulbs arranged in a line to cover half the length of the enclosure. The UVB bulb should be housed in a reflective fixture like the Arcadia ProT5 or Vivarium Electronics T5 HO, and placed on the basking side along with the heat lamp. Make sure that the fixture your UVB bulb is housed in does not have a clear plastic bulb cover.

Since green iguanas are active during the day, it’s beneficial to provide an additional daylight-spectrum lamp to make sure the enclosure is brightly illuminated. This is extra important since you will be using such a large enclosure. Use 8’ of strong 6500K LED or T5 HO fluorescent plant grow lights for best results.

Lights should be on for 12 hours/day. 

What basking temperatures do green iguanas need?

Green iguanas need a basking surface temperature of around 120°F and a cool side temperature between 75-85°F. Measure your temperature gradient with a temperature gun. The basking surface should be a thick, sturdy wood branch or platform laced near the top per the specifications listed in the lighting section.

Provide heat for your pet by imitating the sun with a cluster of halogen heat lamps placed on one side of the enclosure. You will need enough lamps to evenly heat an area at least the size of the lizard’s body, which will take about six lamps. Do not use heat mats, red bulbs, or blue bulbs, as these are not as effective.

Nighttime temps should be no lower than 75°F. If needed, a lightless heat source such as a radiant heat panel connected to a thermostat can be used to maintain the minimum air temperature.

What humidity levels do green iguanas need?

Green iguanas are a tropical species that needs a humid environment to stay healthy. Average humidity levels should be between 60-80%. Humidity should be measured with a wall-mounted digital hygrometer. Daily misting with an automatic misting system and using a humidifier connected to a humidistat is helpful for maintaining high humidity. 

Reptile humidifiers and foggers should only be used with distilled water and require frequent disinfecting to keep your reptile from getting sick.

You will also need to provide a tub of water where your iguana can drink and soak as desired. Change out the water whenever it gets soiled, and give the basin a good scrub with disinfectant once a week. Using a siphon or mechanical water pump and a hose will make emptying and refilling the tub much easier.

What substrate is good for green iguanas?

Although green iguanas spend a lot of time either climbing among branches or swimming down below, using substrate in the enclosure will cover the floor and help provide a cushion in the unlikely event that the lizard falls from its perch. It also helps maintain humidity!

We recommend the following substrates for green iguanas:

• Zoo Med Eco Earth
• Zoo Med ReptiSoil
• Exo Terra Plantation Soil
• Zilla Jungle Mix

Substrate should be at least 4” deep and completely replaced every 3-4 months. Remove poop and urates daily, along with any contaminated substrate.

What décor can you use in a green iguana enclosure?

Green iguanas do not do well in enclosures where they can’t hide, climb, or perform other instinctive behaviors. And heaven forbid that it’s boring! One of the best ways you can help your pet be happy in its enclosure is to fill it with things for the lizard to use and interact with.

Here are some ideas for things to add to the enclosure:

• sturdy climbing branches
• raised platforms
• hollow logs
• additional hiding places (dog/cat kennels can work well)
• live or artificial foliage

All climbing branches should be securely anchored into the walls/floor of the enclosure to prevent collapse.

What do green iguanas eat?

Green iguanas are herbivorous, which means that they eat plants to get the nutrition that they need. Green iguanas should be able to eat their fill of greens every day, with occasional fruit as a treat. Approximately 60% of their diet should be dark leafy greens, with 30% consisting of other vegetables. Chop vegetables into bite-sized portions to help prevent choking.

For a healthy, happy green iguana, offer as much dietary variety as you can! 

Leafy greens for iguanas: collard greens, cactus pads, spring mix, arugula, kale, alfalfa, bok choy, carrot greens, spinach, dandelion greens, hibiscus greens, turnip greens, mustard greens, parsley, romaine lettuce, escarole, watercress, clover

Other vegetables for iguanas: broccoli, rapini, zucchini, cauliflower, sweet potato, bell pepper, squash, carrots, okra, sprouts, pea pods, green beans, shredded carrots

Due to its high sugar content, fruit should be used as a treat. Options include berries, mango, cantaloupe, apple, banana, and papaya. Edible flowers such as hibiscus and dandelion can also be offered.

Supplements

You will also need calcium and vitamin supplements to prevent your lizard from developing a deficiency. We recommend Repashy SuperVeggie, lightly dusted on all salads.

Do green iguanas like to be handled?

Truthfully, few reptiles actually “like” to be handled. Green iguanas vary in temperament, and some are more handleable than others. They require skilled taming and lots of patience. If you try to grab them at the wrong time, they may deliver a nasty bite! However, taming is not impossible. 

When you start handling your iguana, be gentle. Don’t grab the lizard from above, because that will make it afraid of you. Instead, approach from the side and scoop from below. Support as much of its body as possible, especially its feet. Handle inside the enclosure only at first. Start with very short handling sessions in the beginning, then gradually make them longer as your pet becomes more accustomed to you. 10 minutes of interaction daily usually creates a fairly handleable iguana. Emphasize positive interactions, and treats can be used as an occasional bribe. 

If you are worried about bites, wear a pair of thick leather gloves for handling.