At the recommendations from various experienced tomato growers on here, I've tried to grow my plants in a matter that not only helps them grow well, but also help them with disease prevention.

I've already mulched my plants with straw, staked them, fertilized them, and pruned the lower branches that seem to be dragging on the ground (or straw) to help prevent them from picking up pathogens.

The other suggestion included an anti-fungal spray regimen as a preventative measure. I recently bought some Bonide copper based fungicide spray. Do those of you (esp Daniel), spray all the leaves on the plant, or on just the lower ones, since that is where a lot of the diseases seem to start. Also, how often does the spray need to be applied? And, does it need to be re-applied after light shower, or heavy rain?

Any other suggestions would be appreciated.

Thanks.