From south Texas and northern Mexico, Thelocactus setispinus is a globular cactus that becomes more columnar in time. It can be solitary or offset with age and reaches a height of 6 inches and 4 inches across. Flowers are a pale yellow with a red throat and come in flushes all summer long. The fruits are bright red, hence the name "Strawberry Cactus".
     I found one of these at Home Depot all covered in buds. A few days later I took the pictures below. The fruit pic was taken at the end of summer. Click below for more pictures.

Flowering in mid summer

A closer view

A bunch of red fruits