Starting Broad Beans in Pots

Afternoon all.

I have sow broad beans in my schedule for next week, but the bed that will be early beans and peas still has pumpkins growing in it that may still produce harvestable fruit. Normally I'd give it another week to see how the pumpkins do, but I'm going to be away for almost three weeks, so I'm thinking of sowing them now in big pots and then transplanting maybe in November. 

In general. I've found pot-sown broadies do less well, but last year we had torrential rain from mid October up until December so it was impossible to work the ground (heavy, very heavy clay!) and I missed the boat with autumn sown broadies. Spring sown never do so well.

What to do?!!