[DD.]

It's way too late for sets, let alone seed.

The next window of opportunity is in the autumn for over wintering onions, or about August if doing them from seed.

[Aunt Sally]

Ditto

[hubballi]

There must be something I can feed them to get them growing faster ?

[Aunt Sally]

You'd need a magic wand 

[Beetroot queen]

There must be something I can feed them to get them growing faster ?

Or some serious luck, but i dont think you believe in it do you ? 

[rowan57]

Huballi, too late to get anything from seed / set apart from spring onions. Don't worry, there's always next year. I tried Parnsips again this year but the weeds are too fast so I hoed them in again, there's always next year.

[Yorkie]

Too late now for onions from seed