Wave Petunia

Since wave petunias are such vigorous growers, they require a constant supply of water and regular feeding. Feed plants every 2 weeks with a complete plant food, such as 10-20-10 or an organic alternative, to maintain constant flowering. Plants grown in part shade and not fed regularly will tend to be leggy, have pale yellow foliage and fewer flowers. Deadheading is generally not required to keep plants looking neat, but you may want to pinch back errant stems to encourage bushier growth.
Avoid wetting foliage to prevent fungal growth.