Begonias come in a wide range of shapes and sizes, check the label for the final height. Small flowering begonias are often sold as begonia semperflorens or bedding. The well known begonia nonstop(c) grows taller with big double flowers.

begonia cameleon

There is also a wide range of begonias with a trailing or semi-trailing habit often sold as pendula or illumination.

Probably the most popular bedding plant sold it has a wide range of colours but no blue.

begonia semps

Bright vibrant colours and unusually for summer bedding happy in partial shade

They like to be warm and need watering in dry weather.