Growing food in winter – Victoria

I am wondering what everyone’s experience is growing food in winter in Victoria? I transplanted spinach a month ago and it hasn’t died, but hasn’t grown at all either. Snow peas planted 3 weeks ago have sprouted but very slow growth. Spinach seeds planted 3 weeks ago have not germinated at all.

Temperatures where I am are averaging at lows of 3c to high teens during the day.

This is my first year gardening and everything I read online said that these crops would be good in colder weather, but is it just too cold to be starting them now? I am thinking perhaps I should have planted all of these in early autumn to allow them time to become established before the colder weather set in.