Posted: 19/07/2013 at 08:26
Bit of an update for you, I have a few flowers on my tomato plants..
how many times a day would you water the plant in this heat?
The bottom line is water when the plants need it. The mix shouldn't be permanently damp. Don't be afraid to let the mix dry out. I don't mean leave the mix dry for three or four days, but a day without water will not hurt a tomato plant. They're immensely tough, durable critters and will produce at their best if treated as such. More tom plants are damaged by overwatering - and overfertilising - than neglect.
All sorts of factors contribute to a container watering regime. Smaller pots dry out quicker than larger ones, terra cotta dries out quicker than plastic because terra cotta "breathes". The temperature and number of hours in direct sunlight also contribute.
Dove's watering regime (two posts above) sounds about right. You'd need vastly hotter temperatures than you're currently getting to justify more watering.
My toms are in the ground. The temps have been in the mid-30s for a couple of weeks with nothing lower than 22C overnight. I water - very deeply - every four or five days.