[prakash_mib]

I put them in mid march and earthed up continuously and they are earthed up now around 6-8 inches and the plants grew out of it. they are of size 8 inches from the earthing. shall i furtle after couple of days?  .
To give a fair idea. a metre wide fleece is able to cover just about 1 row with leaves squishing a bit.

[DD.]

I think you're at least a month early. They need 12-13 weeks.

[bigben]

I have tended to at least wait until they flower. Does the presence of flowers suggest they are almost ready? (assuming they are a type that produces flowers)

[DD.]

It's a good indicator, but as you say some don't flower.

After 8 weeks, I think it a bit early to furtle.

[Ivah]

I usually plant around my birthday, 7th March, and dig a few around my wife's birthday, 21st May, so I agree you are possibly a bit early even though you are a lot further South.

[prakash_mib]

bit further south is bit nagging me. the earlies on the catalogue said 10-12 weeks

[DD.]

Mid March to now is only 8 weeks. Seed companies tend to be a bit "optimistic".