Quick Scoop

Cut petunias **just above a leaf node or side shoot** on the stem, not halfway down a bare stem. That’s the spot most likely to push out new growth and help the plant fill in instead of getting leggier.

Where to cut

• Trim long stems back to a point where there is still healthy foliage.
• Make the cut just above a leaf pair, leaf joint, or visible new shoot.
• If a stem is very stretched out, cut it back by about one-third to one-half, but leave some leaves on the plant.

What to remove

Deadhead spent flowers by removing the whole bloom, including the little seed pod at the base. Just pulling off petals is not enough, because leaving the seed pod can keep the plant focused on seed production instead of new flowers.

How hard to prune

For most petunias, a light-to-moderate trim works best rather than a hard chop. Garden sources suggest cutting back roughly one- third of the leggy stems, or up to about half if the plant is tired and straggly, while keeping enough foliage to recover quickly.

Aftercare

After pruning, water well and give a light feeding to encourage fresh growth and more blooms. New stems often appear within a couple of weeks if the plant is healthy and getting enough sun.

Simple example

If a stem is long and floppy, follow it down until you see a leaf pair or tiny side shoot, then snip just above that point. That’s usually the cleanest cut for a fuller petunia.

TL;DR: Cut petunias just above a leaf node or side shoot, remove spent flowers with the seed pod, and avoid cutting back more than about one-third to one-half at a time.

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