Sweetcorn - sow all at once, or staggered?

[Incy]

I didn't soak mine just popped them in moist compost in root trainers and got 100% germination. I hadn't realised they could be problematic.

[Currysniffa]

I put mine in a freezer bag with moist compost and dropped them in the heated prop for a day or two, it worked a treat