Mexican Petunia Leaves Curling and Thinning? Prune and Feed for a Comeback

Your Mexican petunias (Ruellia simplex) against the fence are leggy, curling, and pale while others thrive. The pines and oaks nearby aren't stealing nutrients—the real issue is age and maintenance.

Why They Decline

Mexican petunias grow fast and woody at the base. Without regular hard pruning, they become spindly, shed lower leaves, and curl remaining foliage from stress. The shaded, root-competitive spot by the fence accelerates this.

Rejuvenation Plan

1. Cut back hard. Shear to 6–12 inches in late winter or early spring. They'll regrow bushy and vigorous.
2. Feed weekly with a bloom-boosting soluble fertilizer (high phosphorus, like 10-30-10) during active growth.
3. Thin crowded stems to improve air flow and light penetration.
4. Water deeply during dry spells; they're drought-tolerant but bloom better with moisture.

Long-Term

Plan an annual hard prune. In Gainesville's climate, they'll bounce back fast. If the fence-line group never recovers, consider relocating them to a sunnier spot—Ruellia flowers best in full sun.