Ed Stuart said:

O.K., how do I, "maintain good foliage cover"?

Overly zealous pruning of staked tomatoes should be avoided.
If you *are* staking the tomatoes, prune them to two or three stems
rather than one single one. Keep an eagle eye out for pests --
especially hornworms. Limit loss of foliage to disease by good
mulching and watering practices (and maybe preventative treatment
if foliar diseases have been a chronic problem in the past).

--
Pat in Plymouth MI ('someplace.net' is comcast)

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)