The importance of microclimates
Seems like this is a good time to share some information about how microclimates work.
For context, I'm currently rearing a 2026 Ibera Greek hatchling in a 110 qt Sterlite, introducing them to an appropriately sized outdoor enclosure in the spring.
Dimensions of the chamber are 34.63"L x 18.75"W x 12.63"H. Substrate is a mix of organic topsoil, RepiSoil, sand, and orchid bark, which has excellent field capacity and doesn't compact too much. I test the field capacity by squeezing a handful of the substrate tightly in my hand. If water drips out, it's too wet. If it holds shape, moisture levels are good. The substrate ranges in depth from 4-6", sculpted to create depressions and rise. Hides are created with pieces of cork bark, leaf litter, and ample live plants (currently, pothos, fittonia, Draecana elegans, and Dwarf Schleffiera). I treat this enclosure as a bioactive setup; there's isopods and springtails as part of a natural clean up crew.
A sizeable shallow terra cotta saucer is always full of fresh water.
There are numerous pieces of Pennsylvania fieldstone and slate, which serve as both feeding platforms and basking spots. Directly below the 100W basking bulb 14" above the subtrate is a piece of slate; temperature at the basking spot varies between 98-102 degrees during the hottest part of the day when afternoon sun streams in through the large floor-to-ceiling windows of my office, but normally sits between 93-95. If I read the surface temp of the leaf litter immediately adjacent to the slate, it reads 95. Peel back some leaves and read the surface temp of the substrate? 85. Read a few inches down? 78-80.
Now here's where it gets interesting, and shows how temperature zones operate inside an enclosure. Depending where I point the temp gun on the cooler side, surface temps read 75-78. Under the cork bark? 70-72. A few inches down? 68.
All the way at the bottom? 65.
When I read temps first thing in the morning, temps equalize to between 65-70 depending on where I point.
By providing a sufficiently deep substrate and using plants and other natural hides, you can create a wide range of temperatures -- all while keeping humidity high (80-85%) *just under the leaf litter*. As we know, hatchlings spend much of their time hidden and surrounded by pockets of moisture. They will seek out the microclimates they need to stay hidden, hydrated, and at the temperatures required for peak metabolic function --- as keepers, we need to design our enclosures in such a way to allow them the ability to move easily between different zones.