In article , Pam writes:

of the country outside of the extreme southwest that can plant tomatoes
out in March..........I'm in zone 8 and we don't even consider it until
Mother's Day..........

pam - gardengal

I am in zone 8 in the Central Valley of California. I have planted
tomatoes as early as March 15. Sometimes the late date is
April 15. This year will probably be around April 1st. I just
check the night temps; they're in the 50s now. When they
stabilize some, then out will go the toms. The ground is
warming up nicely.
A good coverup for cold nights is an inverted 5 gallon pot.
Covers most size plants and has "air vent holes" for those
sunny mornings so the plants don't "cook"

Emilie
Norcal Central Valley
zone 8