Russian tortoises are primarily herbivores. While many tortoise owners try to precisely replicate a natural diet for their captive pet, this is a near-impossible task with Russian tortoises, since many of the plants they eat in the wild are native to their natural habitat and are not readily available outside of that region of the world. The best thing you can do is attempt to provide a substitute diet that has proven successful with other tortoises and provides appropriate nutrition for your pet.
Good tortoise nutrition includes fiber, protein, vitamins, and minerals. The best way to ensure that your pet is getting all of the nutrients he requires is to feed him a varied diet. Russian tortoises are browsers, so providing them with a variety of foods not only makes sense as far as keeping them healthy, but also because this is the way they will eat most comfortably. The best food you can give your tortoise is a variety of leafy greens, including chicory, clover, dandelion, and thistle.
If you feed a limited quantity, you can feed your tortoise every day. Overfeeding shouldn’t be a problem, as long as you are feeding a variety of low-nutrient plants, such as weeds and grasses. Tortoises are generally most active in the morning and late afternoon, so these are good times for feeding. If you can, scatter the food throughout your pet’s habitat so he can browse for it. All uneaten food should be removed once the tortoise is no longer active.