You are doing it all wrong. Here’s the right way to prune petunias

Step 5: Trimming Overgrown Stems
Next, trim back any overgrown stems to maintain a compact shape. Cut back to a leaf node, which is where new growth will emerge. This helps prevent the plant from becoming leggy and encourages bushier growth.
Step 6: Shaping the Plant for Optimal Growth
As you prune, consider the overall shape of the plant. Aim for a balanced, rounded shape that allows light to reach all parts of the plant. This not only improves the plant’s appearance but also promotes even growth.
Step 7: Cleaning Up After Pruning
After pruning, collect all the clippings and dispose of them properly. Leaving debris around the plant can attract pests and diseases. If you’ve removed any diseased material, be sure to clean your tools again to prevent spreading pathogens.
Step 8: Monitoring Petunias Post-Pruning
After pruning, monitor your petunias for signs of stress or disease. Ensure they receive adequate water and nutrients to support new growth. With proper care, you should see new blooms within a few weeks.
Tips for Maintaining Healthy Petunias
In addition to regular pruning, maintain healthy petunias by providing them with well-draining soil, regular watering, and balanced fertilizer. Deadhead spent blooms regularly to encourage continuous flowering, and watch for signs of pests or diseases.

Conclusion: The Benefits of Proper Pruning
Proper pruning of petunias not only enhances their appearance but also promotes healthier, more vigorous growth. By following the right techniques, you can enjoy a garden full of vibrant, blooming petunias throughout the season. Regular maintenance and care will ensure your petunias remain a stunning focal point in your garden.