I have the same problem every year, because I tip the plants to get a bigger crop, they always seem to split at the junction, once the heads get to a certain size, get filled with rain (heavy) and then the wind has its wicked way.
I always rescue them by taping them up with insulating tape which works fine but the slpit might stress the plant and make them hermie.
Next year, as soon as the stem has finished growing and the bud has started to form, I am going to tape them up before they split and give them some extra strength. Together with one or two canes, I hope that this will do the trick.
As for them falling over, try a short but thicker stake at an angle to the ground like they stake young trees these days.
Magpie