This is a special concern when keeping herbivores and lizards that drink droplets of water from the leaves of plants. When real plants are included in the environment it is suggested that they remain in individual pots. If the terrarium is a wood-framed cage, the use of a false bottom can be advantageous. Assuming that the bottom is constructed of plywood, it is fairly easy to locate the areas where the plants are to be positioned and cut out holes of appropriate sizes that will accommodate the corresponding plant pots. When the pots are arranged a suitable substrate can then be applied to cover their tops.
There are several types of natural-looking gravels that are manufactured primarily for use in freshwater tropical fish aquaria. These substrates are well-suited for use in terraria. A potting soil mixture can be used in place of gravel. Regardless of the medium that is used to cover the floor of the terrarium, cleanliness must be maintained, and periodic replacement of the gravel or soil is recommended. If a false bottom is in place, the substrate can be changed with much less disturbance to the plants.
Decorations of the temperate/subtropical environment should reflect the natural habitat of the individual species. Terrestrial lizards should be provided with plenty of ground cover, such as horizontally positioned branches, pieces of tree bark, and rocks that are light enough for the animals to burrow under. Upright branches might also be included; even those lizards that are considered to be terrestrial will occasionally climb if they are furnished with the means to do so. Arboreal species can be afforded some ground cover in their environment, although the main concern is the provision of twigs, limbs, and branches that offer the lizards a variety of perches that are located at different distances from the overhead heat and light sources. Driftwood, although usually expensive, can be a very attractive addition to most terraria.
Whether the decor is comprised of branches, driftwood, or small and/or large stones and rocks, the safety of the inhabitants of the habitat should be considered. Rock formations and arrangements of branches should be secured to prevent the specimens from being crushed by an unstable construction of scenery. Also check for sharp splinters and ends on branches, as well as unusually sharp edges on rocks and all other decor.