Outside habitat for sulcada tortoise

HI! My daughter is making an outside habitat for her sulcada tortoise since he is growing and needs more space (We live in California).The area she is preparing for him is now barren of grass and plants. We are planning on planting grasses and weeds in his area. The problem is the soil. It is clay like and we need to add amendments to plant the grass. We found a natural organic amendment but it has Bat Guano and oyster shell (will this hurt him?). The amendments will be mixed with the clay like soil and the grass planted. With in three weeks we hope to have the grass full enough to put him in the enclosure. Do you think the amendment will be okay for the soil or will it effect the health of the tortoise? What are your thoughts on sod (it's already grown grass, no waiting time)? When we purchase plants for his enclosure, how long should we wait before we plant them in his enclosure? We understand that commercial plants have been fertilized and may be harmful for him. Thank you for your time and help in this matter.We want to do what is right for this little guy so he will continue to grow happy and always be healthy.