I'm a newbie to serious gardening, but I have a very basic question.

You buy some transplants like zucchini or squash. The pot contains usually two, maybe three seeds that have sprouted. Do you a) transplant the pot, then cut away the weaker seedling, or b) let them both live and compete side by side.

Logic says 'a' , but a surprising number of people I spoke with chose 'b'--just let them fight it out.

Is there any evidence as to which would be more productive, a single noncompeting plant, or two competing plants?

(And I assume if you're using a trellis for tomatoes and cucumbers and melons, you thin to allow the most vigorous vine to thrive, no?)

TIA for any comments.