A well-planted, secure, spacious outdoor pen is the best housing for all species of tortoises. If it is done well, you should not have to offer any supplemental care all year! This is more of a ‘basic concepts’ article than a ‘how to’. See the Resources at the end for good ‘how to’s’.
Size and location
Find a good spot for the habitat. The space should allow plenty of room- at least twice that recommended for indoor housing. The best location will offer sun and shade, some hilliness, good drainage, easy access to a water supply and ideally an electrical outlet.
For security’s sake, it is also best if an escaping tortoise or intruding predator would have to pass two separate barriers to accomplish their goals. This can be a well-built pen within a fenced yard where the fence has few escape routes. Most yard fences are very open on the bottom- that can be dealt with by blocking the gaps with stonework or driving stakes into the ground to block escape.
There is no really wrong way nor perfect way to build a tortoise pen, but there are a few considerations.
A good water dish is needed. You can sink something like a large plant saucer, or make a cement pond, or add a water feature, but be sure it is always full and clean, and that the tortoise can easily drink from it as well as getting in and out of it. A food dish can be something as simple as a flat stone or tile.
Hides are always important. Examples of outdoor hides include…
I generally offer at least two actual ‘get out of the heat and rain’ hides, and several hiding places.
Plant the enclosure heavily with foods to nibble on and plants that provide cover. Remember- most tortoises are reclusive by nature, and forest tortoises spend much of their day under some sort of cover.
This is more of an idea than a plan. Why not make a tortoise enclosure beautiful and functional by planting foods that humans, the tortoises, and birds and butterflies enjoy? At the same time, why not aim to have something blooming all the time?