Answer: The answer to both your questions is pinch often and hard! Pinch off the spent flowers, before they begin to form seeds and the plant will put its energy into developing more flowers rather than developing seeds. If you take a few inches of stem when you pinch off the spent flowers, you'll encourage the plant to develop new flowering stems. In most cases, when you pinch off a few inches of stem, the plant will respond by producing two flowering stems where there once was only one!So, instead of getting leggy, they'll be bushy and full.
Best wishes with your petunias!
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