[m1ckz]

so lovelly an sunny here   was thinking of a row of carrots    or  is it too early

[DD.]

4 or 5 weeks yet, here. It's easy to be lulled into a false sense of security!

[Mattgregory27]

I sowed a row last year at this time under a clear plastic tunnel cloche along with parsnips and had very good results. I sowed a row last weekend to see if I could get the same results tis year. I sowed early Nantes last year and have done so again.

[Ivor Backache]

The temperature in the conservatory was 21 deg, and outside it was 14deg, but the soil temp was just 8 deg., and that is the one that really matters. Bury your hand in the soil and you will realise how cold the ground is.  Daffodils are about 2 weeks behind last year to flowering and that is my yardstick.

[beesrus]

It's all about your own local climate and the weather.
I also sowed carrots this time last year under a cloche, and ended up with a well decent crop... Nantes carrots on 1 March, germinated 16 March. In fact the only problem I encountered was the prolonged dry spell later on, which resulted in a fair bit of swelling and splitting due to my under watering in the hot spell, followed by a lot of rain.

But I do note looking back, the temperatures were a good 3 degrees warmer last year than this, through Feb and March.... in fact March 2014 was almost Summer like.  This is the value of keeping records.
So, I'll give it another couple of weeks for the outside carrots. Mind you, I've already got a small crop just sown in the greenhouse, so I'm cheating a bit, and will still get my small early crop.