Yellow Leaves on New Knockout Roses in Houston Heat

Five newly planted Knockout roses in Houston show yellow leaves despite new growth and regular deadheading. Sprinklers run every other day in 100°F+ heat with no rain. Is overwatering the issue?

Heat Stress, Not Overwatering

Newly transplanted roses need twice as much water as established plants. Sprinklers often wet only the surface; hand-watering deeply is essential in extreme heat.

What's Happening

• Yellow leaves are a heat-stress response.
• Plants may drop all leaves but will regrow when temperatures cool.
• Knockouts are not immune to heat stress despite their reputation.

Action Plan

1. Water deeply daily (not just every other day) until heat subsides.
2. Apply mulch to retain soil moisture.
3. Do not fertilize during heat stress.
4. Wait for cooler weather—plants will recover.

Your roses won't die; they're conserving energy. Consistent deep watering is the best support you can give.