Flowers Aster.

What is the difference between a mum and an aster?

They look pretty much the same to me.

Actually the Chrysanthemum family has been redivided into several over the last 10 years or so. But the common mums you are probably thinking about vary in flower type (cushion, daisy, button, football, spider, and spoon petal), has a wide range of colors, and plant sizes from compact to 3' or more (footballs). The leaves are deeply lobed and somewhat serrated, while the color foliage is an olive to medium green. Bloom time is early fall. Best if pinched each spring to encourage branching. Also best if divided every couple of years and replanted.
Asters blooms pretty much fall into the daisy form, most are small, but some to 2" The color range is more limited with blues, lavenders, and purples dominant, but pinks and whites also available. The Aster foliage is darker green, almost a blue green, and usually with a small slender leaf. There are compact varieties to about 18" but many get 3' or more. In most areas, they are hardier perennials, requiring less maintenance. They bloom usually at the end of summer, prior to fall. 

 

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