I am often asked about the types of plants I use in my tortoise enclosures. It's important to choose varieties that are not only appropriate for your location (and even zone) but that are safe for your animals.
Plant life inside an enclosure is an important addition to bringing the entire unit together. In nature, all turtles and tortoises are surrounded by various forms of vegetation which they use as both food and cover. In captivity it can be very difficult to keep edible plants alive long enough since the tortoises (and even some turtles) will constantly pick at them and eventually mow them down. In our outdoor enclosures, springtime triggers a wonderful display of weeds and wildflowers to begin blanketing the majority of the ground.
Upon emergence from brumation, the animals are more concerned with basking and only nibble here and there which gives this vegetation a running start to really expand. By mid to late spring, certain species begin consuming large quantities of these naturally growing edibles and by summer, the grounds of the pens are nearly bare. This is one of the reasons why it is so crucial to plant other life within the enclosures that the animals do not necessarily want to eat (but safely can if the choose to) or cannot reach with their mouths.
Hungry tortoises will not hesitate to actually climb up into a plant to eat its leaves! It can be frustrating for the keeper especially if you’re like me and enjoy beautiful, naturalistic pens with flowing vegetation. Since we consistently offer our tortoises food items in addition to the vegetation in their pens, making sure they can eat their plant co-inhabitants is of secondary importance. Of course one would never want to plant something toxic, so instead, we plant hardy items that can either take some tortoise-power or are just not a preferred food. What’s primarily important is that the plants offer refuge and visual barriers. In the wild these animals do not occur completely exposed while resting on a bare ground of dirt. Simply put, they would fry in the blazing sun. Most species actually will become “freaked out” if they sit vulnerable to anyone or anything because they do not have cover to escape under. These are wild animals at heart no matter what, and they are instinctively programmed to hide from potential threats. When they don’t have the chance to do this, we are once again dealing with stress.
Large grasses are an excellent way to provide cover and the animals do not eat them (with the exception of very large tortoises like Aldabras, for example. Fountain or maiden grasses are a preferred choice here and they come back each year fuller and larger. The tortoises waste no time making scrapes around the bases of the grasses and can easily cool off under them during very hot days. Knockout rose, although edible, is typically left alone by the tortoises. These grow large and feature stunning flowers of pink, red or yellow… just watch out for those thorns! As the petals fall, the animals may choose to snack on them. Spirea plant varieties are some of my favorites. These also grow large and full, come back each year and are very attractive. The only negative aspect of spirea is that the animals will eat them. They are easy to climb into and the leaves are delectable, it seems. Tortoises will strip them bare. Either start with already established large spirea or be prepared to fence them in so the tortoises cannot access them until they mature and fill out. Yucca is a very hardy perennial that appears as if it were a desert succulent and as it grows it provides shade from the sun. The tortoises do not eat it.
Hibiscus trees and plants are absolutely great choices and up here in the northeast, the hardy varieties make it through the winter just fine. Both the leaves and flowers are edible and favored by the tortoises. They are a constant source of food as leaves and flowers drop throughout the active part of the year. The trees are tall enough so that the animals cannot reach anything and destroy them. At the end of the summer, we remove all hibiscus and feed them out to the animals in full. We then start over in the spring with new ones.
Mediterranean heather is probably my all-time favorite plant to use. It's hardy, blooms throughout winter and is incredibly natural looking for tortoise enclosures, particularly for the species that hail from....well, the Mediterranean. It's safe for them to eat but they rarely (if ever) attempt to eat it. They do love to hide in and around, though. It's one of the very first plants that garden centers will carry in early spring. I highly recommend it!
When planting any of these items, it’s wise to clump them together in random parts of the enclosures to make nice thick areas of refuge. Of course as they grow and enlarge they may need to be trimmed especially being so close to each other but that is another thing that is of secondary importance. The well-being of our tortoises and turtles comes first and we are trying to replicate nature as best as we can. Plants do not grow in neat little rows in the wild. They grow wild! Remember you are creating a habitat for a wild animal and although the placement of these plants may not follow a typical gardener’s rule of thumb, it can still be beautiful and captivating. It also gives you peace of mind knowing your animals can safely access hiding areas by supplying them with appropriate plant life. There is a wide range of plants one can use in an enclosure that are safe for the occupants. It’s best to do thorough research on what can grow well in your particular area. Because New Jersey experiences all 4 seasons, we prefer to mostly use perennials outdoors. It saves us money and the plants come back better each year.
As always, it's best to use natural as a model. Study a specie's natural habitat and you'll surely gain some ideas!