Question
I have a restaurant in Miami, Florida and I am installing 6 large
planters around my outdoor cafe. I have NO idea what I should plant
in them. The planters are 16" wide, 24" deep and 48" long. They are
massive. I want to create an air of security because the cafe is right
on the corner of a scary intersection. I also do not have an easy hose
access so Id like to plant something that doesnt require much water. I
was thinking areca palms or bouganvelias. Any suggestions?

Answer
First, your in Florida...in tropical and HOT Miami... growing plants in a planter with no irrigation...not to be sarcastic...but your search for something that will grow well in a planter with little water and still provide some sort of visual screen is going be almost impossible. A planter will need water at least every three days and maybe more in hottest driest times. I would plant some form of ficus hedge.
Look for 3 gallon ficus shrubs at local nursery. If not a ficus try a podocarpus.
One of those should work well. You need to buy 3 gallon size for your planter, they should be about 30" tall and plant them three in each planter evenly spaced apart to fill. Put a layer of 3" of gravel in the bottom and cover it with filter fabric (weed fabric). Fill the rest with good organic potting soil. It will be best to add some form of slow release fertilizer and water saving soil improvements that hold moisture in the soil. Cover the surface of the soil with a layer of cypress mulch to hold in the moisture and prevent splashing of soil in rain. Or you can use a decorative gravel such as BLACK Mexican beach pebbles or other colored rocks.

Best of Luck
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