Petunia care guide

Petunia × atkinsiana

Also known as: Garden petunia

Pets and children

We haven't been able to confirm how this plant affects pets or small children. If any is eaten, consult a veterinarian or a doctor.

How often to water Petunia

Spring–Summer (Mar–Sep)
Every 2 days
Water thoroughly at the base once the topsoil dries, keeping water off the flowers, as a guide; in midsummer check every morning.
Autumn (Oct–Nov)
Every 3 days
Plants cut back in summer flower again now; as a guide, water about a day after the topsoil dries.
Winter (Dec–Feb)
Every 5 days
For a plant kept under the eaves or indoors, water sparingly about two to three days after the soil dries, as a guide.

Light and placement for Petunia

A sunny spot is about right; rain melts the flowers, so a place under the eaves out of the rain suits it, and in poor light it generally flowers less and grows leggy.

Overwintering Petunia

Overwintering guide: 5°C (41°F) or above

Usually treated as an annual, but cut back in autumn and kept under the eaves or at a window out of frost it can sometimes overwinter; as a guide, keep it above about 5°C and water sparingly.

Fertilizing and repotting Petunia

Fertilizer

A hungry plant: while in flower, liquid feed about weekly or slow-release fertilizer about monthly is the usual guide, and when it runs short the flowers shrink and thin out.

When to repot

Spring–Summer (Mar–Sep)

Common problems with Petunia

  • Rain melts the flowers and the wet plant rots.
  • Without cutting back, the plant goes bare at the base and flowers only at the tips.
  • When fertilizer runs out, the flowers shrink and stop.

Tips for growing Petunia

  • Pinching the young plant gives more branches and a fuller mound of flowers.
  • Cut the plant back by about half before the rainy season and again in late August for flowers into autumn.
  • Pick off spent flowers together with the calyx so no seed forms.

These are AI-generated general guidelines. They vary with the variety, the placement and the pot size. For effects on pets or children, consult a veterinarian or a doctor.

Keep your plant log going

Greenery is a free app that keeps your plant care going, with watering reminders and photo records. Available on iOS and Android.

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