It is a great Botanical Garden, considering how hot and dry San Antonio can be in the spring and summer.
There are a number of exhibits in the way of open gardens (rose garden, the garden for blind and more), Lucile Hall conservatory buildings housing tropical and desert plants and a Japanese garden.
Get lost in time along the Texas Native Trail as you explore wildflowers and plants on your own. You come across flocks of duck and geese, models of old settlement homes complete with wells.
There is something for everyone. People looking for a leisurely stroll among flowers, people looking to learn more about nature or for adventure seekers with the little hike along the trail.
There is a restaurant near the entrance, though I have not tried it, but I hear good reviews about it. There is a pretty gift shop, though overpriced as can be expected in such places.
March/April may be the best time to visit as anytime after May becomes unbearably hot!