need some advice on temperatures and seeds!!

Hey guys
So i'm thinking of starting my grow soon but the temperature here is still pretty low, like today the high is 9C and the low at night is still is about 3C it wont go below freezing again but still i'd like to know what the lowest temperature i could get away with and still have them live?

also i bought some seeds online and there for indoor use but i'm wanting to plant just a few soon, is this possible like i think they would still grow just not as good maybe?

i'm planning on going out tomorrow and finding a few spots for my big grow,
i'm going to use some clones and seeds to start them off.

My master plan is too start germing them round the 9th and them putting them outside around the 18th.

thanks

I'd suggest checking with a local garden store to find out what the average date of the last frost is in your area. Just ask them when it's safe to put out your tomatoes.

Well you cant just put the plants outside after the last frost can you, doesnt it have to be about an average of 10C or somethin

thanks