Most of the time, anyway… Although we didn’t visit any gardens, not even the Boboli in Florence (lack of time and energy, sadly), we saw lots and lots of container gardens everywhere we went. Let’s start with a huge pot from Impruneta, this one found in a courtyard at the Palazzo Riccardo-Medici in Florence. 
Okay, not a container garden, but it sets the tone for classic terracotta pots.
Here’s a typical balcony planting. You can see the cactus as well as the laundry drying. 
This is a plant I should know, clearly Mediterranean, but I’m blanking. The most amazing thing is that, as far as I can tell, it’s planted in two terracotta pots, one on either side of the doorway.
Bougainvillea?? Here’s a closeup. The flowers have almost a papery quality.
Lots of succulents, as you might imagine in this Mediterranean climate. Here is a window pot in Volterra,
and another one. 
This array of xeri-plants including cactus and yucca was outside a house in Montalcino on our way into the main piazza. Below is mandevilla in a windowsill.
They also had some beautiful geraniums. I know, you don’t usually think of geraniums as beautiful, but in this case they are perfectly proportioned and fit the color scheme of the shutters just right. 
I like this shot of sprawling ivy geraniums against the view of a narrow street in Montalcino.
This picture was taken from the bus coming back into Florence on our last day. I’m not sure how the gardener waters these plants — does she crawl through that tiny little shuttered window, or does the low wall really hide an inset terrace? 
Caroline's Garden and Travel Record 