Ah, these are dwarf French beans that I can cloche that I've already started, I'm doing two sowings, one direct later in May. My CFB will be late April/early May too.
Corn is also sown in two lots, I am risking an early sowing but have a backup later just in case! Lucked out last year, we will see how this year pans out. Although having read Jeannines advice about corn will probaby make this second lot a bit later... ;D