i think you might be pushing it abit.7c is probably as cold as it wants to be for tomatoes.i grow mine in a heated greenhouse but the books say min 7c in a cool one.

thanks for the info...ive bought a bio green 2.8 heater .i have it set to come on at 8c.
hopefully that will work .i have geraniums as well as scadoxus multiflorus and we are expecting some snow on tue/wed in ireland .who would believe it in march. Anyhow thanks for the info
brian