Guide to Growing Petunias

Gardening Tips

growing petunias with pink flowers

Petunias may be the most delicately named plants in existence. But, do not mistake these colourful flowers for a demanding garden choice. Let us here at Perth Gardening walk you through the eight steps of cultivating petunias the right way:

When to plant petunias in Australia?

  1. Consider where you want to display them. Grandiflora petunias are larger; grow them in hanging baskets away from rain. Multiflora petunias are smaller, but are more resistant to weather.
  2. Choose between seeds or cuttings. For seeds, you have to cultivate them indoors for three months or until they grow three leaves.
  3. Plant the grandiflora petunias in soilless mix. Multiflora petunias thrive in beds with light, well-drained soil. Plant them at least 30 centimetres apart.
  4. Shelter the petunias from wind. They will still bloom in partial shade, but avoid this if you can.
  5. Fertilise the flowers once a month, twice as much for double flowered-cultivars.
  6. Regularly deadhead faded or wilted petunias to prolong blooming.
  7. If the petunias have bite marks, but you see no visible pests, check for night visitors such as slugs and earwigs.
  8. Immediately remove mottled or discoloured petunias. This is a sign of a tobacco mosaic virus (TMV) infection, caused by contact with tobacco products.

In addition to the eight steps of growing them, here are eight facts you should know:

  • Petunias need as much sun as the sky can provide.
  • This is contrary to their being in the taxonomical family Solanaceae, or nightshade.
  • Petunias will bloom all year long with regular fertilisation and carefully maintained water levels.
  • There are 35 known petunia species, with more than 400 different cultivars.
  • Petunias are native to Argentina, one of the world’s leading producers of tobacco.
  • The Solanaceae family is closely related to Nicotiana, where tobacco is classified.
  • TMV was the first virus ever discovered. The first evidence of its existence emerged in 1892.
  • Petunia violacea, an uncommon species, is a famous hallucinogen smoked by people in Ecuador.

Petunias are one of the simplest and most beautiful flowers you can add to your garden. If you need assistance getting started, creating an ensemble of colours, learning more petunia facts, or just want to chat about plants in general, Perth Gardening is here to serve, plant, trim, fertilise, clean, prune…

Contact us today.