Specialty Gardening: Does anyone have the secret to growing petunias ALL summer?, 1 by joannabanana

joannabanana wrote:
I find that petunias need extra fertilizer starting in August. They will be a bit root bound and it helps to give the a good blast of fertilizer with a high middle number every couple of weeks until killing frost. Also, I hand water the petunia pots daily with a very diluted fertilizer amount in addition to the fertilizer blast of the entire garden.

You will find they will perk up and take off within a week or so. remember high middle number.