• Plant them on a slope, in free-draining soil. Agaves aren't cactus, but they don't like to be over-watered. As you can see from this photo, the slope here is enough to allow water to drain away, even when we get the heavy summer thunderstorms. They do need supplemental water, so they're on the drip system.
• Plant them far away from where people may be walking. Those needles are razor sharp! Having something so deadly close a sidewalk, or where people might brush into it, is a very stupid idea. All of my agaves are several feet into the garden, and some are way in the back. Beautiful, but dangerous!
• Do your homework before you buy an agave. Find out if it gets really big, and if it *pups* a lot (sends off a lot of offshoots). The ones that you see here stay fairly small, and don't pup much. You can see a pup there next to the mother plant of an Agave Parryi. When I see them, mostly I just dig them out, but a few I leave if they're growing far enough away. There's another slightly larger pup just up the hill (out of the photo), which is doing well, and which I will leave alone. If you get an agave that gets gigantic, and pups like crazy, your yard will become overrun in no time. I've had these agaves for several years now, and they behave.
So there you go. Agaves are a nice companion plant for palms and cycads. Highly recommended for your tropical desert landscape!