yes you can. I prefere to start some off in pots indoors the rest I sow directly into soil. Mine are already outside under plastic

I always sow direct into the soil less root disturbances.

As with any root vegetable sow directly into the soil... If you sow in a pot/container then transplanting you will disturb the roots which will cause a problem. Whilst not as much of a problem as tap rooted veg. i.e. carrots and parsnips, root veg do far better grown in situ. Hold off sowing until the soil temperature is at least 4˚. This is a late year for starting any veg. so you have plenty of time. It is fine to start brassicas off in ells or seed trays but not root veg!