Seeds from supermarket tomatoes?

[Irish grow bag]

Hi all, I have taken seeds from Tesco baby plum tomatoes and planted them in green house. They are growing fine , but how can I tell if they are bush variety for pruning purposes, the first flowers have set. There are a lot of side shoots.

[airconednightmare]

there isn't really a way to tell other than wait and see. you could try pinching half of them to avoid having all your eggs in one basket.

also there's a good chance that the tesco toms were f1 hybrids, in which case the seeds won't produce similar plants

[Irish grow bag]

Was thinking that about the hybrid, I have a few from bought seed as a back up just in case. Thanks.