General gardening topics

How to grow petunias in hanging baskets

Last updated on April 6th, 2022

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If you have hanging baskets sitting around your garden table, but you don’t know what to put in them, consider growing Petunias. 

With some initial effort, your garden can come alive with an array of colours all summer and they are perfect for growing in baskets because you don’t need too many plants and they are one of the easier baskets plants to deadhead as the flowers are not ridiculously tiny. You can also get away with just planting the top as they trail spectacularly well.

You may also see plants called Surfinias that are usually sold in single pots that look identical to Petunias. This is because they are a type of Petunia so these are also perfect for hanging baskets and often you get a better selection of colours to choose from.


It all starts with planting. You need to find a spot for your basket that will hang in exposed sunlight all day because they like plenty of sunshine.

Once that is done, you need a variety of Petunia that will make the most out of the shape and design: cascading Petunias. Cascading varieties commonly known as trailing Petunias produce flowers that rest on flowing stems so they will hang downwards and extend the colour you get, literally. 

Find a hanging basket that is a good size, we recommend at least a 14-inch basket but you can get away with planting three 9cm plants in a 12-inch basket if this is what you have to work with. The hanging basket should be filled with a good quality hanging basket compost, one that is marketed for its moisture retention because the compost will quickly dry out as they get become established and take lots of water so anything you can do to store water is welcomed. Avoid using standard garden soil as this will compact too easily in a hanging basket and impede drainage. 

At the time of planting, mix in a slow-release fertiliser to aid your new plants and we also ercommend adding some extra water-retaining granules too. 

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Caring for Petunias


Water can make or break the growth of your plants. Petunias, when in hanging baskets, need to be watered whenever the top few centimetres are dry to the touch. This timeline will vary depending on where you live and what the conditions are. During the summer, for example, they might need watering daily but if there is a particularly hot week, maybe twice daily. 

If they are newly planted they will likely need watering much less as the soil will be able to retain moisture but as the plants establish they will need watering much more frequently. This is why we recommend using larger baskets as it’s easier to keep the compost moist.

When you water, water deeply until such time as it drains out of the hanging basket. This is important; without allowing proper drainage, the soil can remain soggy and promote the growth of fungal diseases and root rot. 


They should be fed weekly with a water-soluble fertiliser when in flower. This will work side by side with the slow-release fertiliser you put in the soil at the time of planting to sustain the Petunias all season.

Deadheading to promote continuous flowering

Deadhead the spent flowers as soon as possible so that the plant doesn’t go into seed, but rather, continues to flower and bloom. 

By the middle of summer, you can cut back your Petunias to half their size if they are taking on a scraggly appearance (which is fairly common) and this is something that will rejuvenate them and get them looking great again.

Related articles

The best trailing plants for creating an inspiring hanging basket

Working out how many plants you need for your hanging baskets

How to securely fix your brackets to a wall

Last update on 2024-03-26 / Affiliate links / Images from Amazon Product Advertising API

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