[stephent]

I sowed my onion seeds around 2 weeks ago. Went down today to check them out, expecting SOME kind of life, but found naff all.

Is it too searly to start sowing direct? 

Should I just leave them in, or sow more in a few weeks when it warms up?

[JayG]

Some seeds sown outdoors or in an unheated area now will be experiencing soil temperatures way below the optimum for quick germination, the problem being that they need to be sown early because they need a long growing season to mature (onions are one example, parsnips another.)

In case you haven't seen it, THIS chart provides some useful information, and possibly explains why yours are taking a long time.

Probably a good idea to put them somewhere warmer until they germinate, then you should be able to gradually introduce them to somewhere cooler.

[DD.]

I wouldn't consider sowing any seed direct at this time of year.

Even peas!