cucumber plants

"it has five seeds so I think I should buy another packet then"

Don't mean to sound "Nanny" but are there actually only 5 seeds in the packet, or does it just say it has 5 seeds printed on the packet? Quite often them have more seeds than they say. I have a "fondle" of the packets in the garden centre to try to get a packet with some extra

"At the moment I have staging-will I need a greenhouse border to fit them all in do you think?"

They are a climber, so you need to get them low down so they can climb up, but they mostly climb on a single "vine", and they will reach staging height pretty soon, so you may want to put the pots / grow bags on the ground, but "accommodate" them through / round the staging - or take that section of staging out for the summer