[Endymion]

Are they hard to grow?

Put some seed in today, as well as some more for salads, will let you know how well they've germinated when we get back from our break.

Hmm, the 'summer' radishes have germinated but there's no sign of the winter ones that were also direct-sown so either they're slower to germinate or are less reliable.

Any idea how long I should leave them before sowing some more? (no clues on the packet!)

[sunshineband]

Can take around ten days as I recall --   

[Robster]

I have grown Mooli radish.  Ver easy.  Large white roots easy to clean, peel an slice.  Last well in the ground and can get quite large (and tough).  Well worth it