Radishes Bolting

My radishes seemed promising at the beginning of the season. The leaves were growing healthily and the root was bright red. However, they decided to start bolting. Flower buds were forming at the tips and the stalk was becoming thick and tall. I can think of three mistakes. The weather is getting too warm. The soil was not kept moist at all times. And, the red root should have been underground. Maybe next time.