Empty plot over the winter - to cover or not

What about sowing some Phacelia there? I'm sure I read somewhere that it can be sown in October and you'd have flowers in the spring. Maybe you could run a mower over it when you want to put the dahlias in?

Deffo plan to utilise some of this so will let you know the results Veggie  Going to order some seeds now.

Straw bales are cheap to buy Scarlet, though I have no idea how many you would need to cover an acre(eek)

Just wondering what you have done in the past? The cost of covering that much land is going to be really expensive, whatever you use.