[wapello]

  How can i stop my cauli's from bolting,,,?

[lettice]

Could be many things.
But some things important to cauli success are;
Need to be firmed well in when planting.
Water well at planting and during its growing time, do not allow to dry out.
Space well between plants.
Of course do not forget to feed them too.

[Goosegirl]

This hot weather may not have helped as direct sun makes the curds grow quicker which will make them produce "flowers" which you don't want. When you see the cauli forming right down the middle of the plant bend the main leaves over it for shade, or plant them in a semi-shady spot. 

[al78]

My first thought is lack of water. The whole of May and June so far have been very dry in the south of England. I need to water my brassicas I transplanted last weekend as it hasn't rained since then or before.