Not sure what Menards is, but putting live plants in with your leo is great.
Succulents are perfect, because not only do they like the same semi-arid conditions as Leos, but they don't reqiure much watering or fertilizer (in fact, overwatering and overfertilizing them are the surest ways to kill them). Besides, they look great in a 'desert' sorta way.
The issue then becomes the debate over UV light and Geckos. Most people will tell you its not a bad thing but not necessary. My (admittedly inexperienced) opinion is that they don't like the bright light at all, but if you give your Leo lots of dark hideaways it'll be all good. You'll want a full spectrum 'plant' light on for a good 12-14hours/day.
My tank is home to a pot of various Sedums, a string-of-hearts hanging plant, and a little Jade tree.
Ron Tremper's book has a small section on this subject. Just be sure they can't hurt the kids (cacti and such).
You'll want to make sure you rinse them very well. Depending on how the plant is potted. It would be a good idea to remove the soil and repot them with eco-earth or suppersoil. Most are a bit root bound in the stores anyway. Regardless, make sure you use something with out chemical additives, fertilizer, perlite....Rather be on the safe side.
You will probably need some type of UV lighting for some med-high light plants. The plants in my Tropical tanks really responded to Exo-Terras 5.0 florescents. I've never put plants in with my leos, but do have planted tanks for my leaftails. Hope this helps