Kevin Parker is a senior horticulturist at The Greenery Garden and Home. He says petunias are probably one of the easiest summer annuals to grow, not to mention the most "spectacular".
"They are spectacular when they flower. Petunias are one of the best annuals for colour, really," he says.
How to plant petunias
Petunias come in various flower types and colours and can be grown from seed in your garden. But the quickest way is to buy seedlings from your local nursery.
"The most effective way is to buy punnets and plant them out of punnets," says Kevin. "Look for semi-advanced punnets and start to flower. There will be instant colour when you put them in the garden.”
How to care for petunias
Kevin says it doesn't matter whether you plant petunias in a pot or on the ground. The secret to growing petunias is the sun!
"Plant petunias in a full sun position; they love the sun," he says.
Petunias love the heat and thrive in warm climates. As soon as the weather starts to cool, they will die off.
Petunias prefer free draining, good, quality soil in the garden, or you are growing them in a pot - you use a potting mix.
Petunias need to be watered, but they don't like to be drenched.
Kevin says, "Petunias aren't the sort of plant you have to water every day, but if the weather was hot, you wouldn't have to keep watering that much. They are pretty drought-tolerant plants."
Petunias need to be fed continuously to encourage growth and flowers.
The secret to growing bigger and brighter petunias
After planting your petunias, Kevin says the secret to getting bigger flowers with more colour is to remove the first flush of growth.
"The plants want to flower very quickly, but it's better if you remove the first flush of flowers, and even the second flush sometimes", he says.
"This discourages the plant from putting all its energy into flowering straight away. It also helps the plant to establish better, so you get a bigger plant with many more flowers later rather than a small plant starting with the odd one or two flowers."
How to care for potted petunias
Similar to planting petunias in the ground, they require full sun. If your pots are in the shade, your petunias will struggle to bloom. Ensure the pot has drainage holes, and keep an eye on the soil. If it's too wet, your plants can rot and die off.
How do you keep petunias blooming?
It takes a lot of energy for petunias to flower, so it's common for them to run out of puff mid-summer.
"What you can do is cut them back to even a third or a half of the plant, feed them and the warm weather encourages them to reshoot and regrow," says Kevin.
"So you can sort of get two crops out of the flower."
How to revive a dying petunia
If your petunias are dying, it's good to work out why. Kevin says if it's the middle of summer and your petunias are dying, they've probably had too much water.
"If there is any green left in the plant, then sometimes you can cut it back, and when you do cut them, you need to feed them. The feeding helps to encourage more growth."
"If it died back and browned off, it might have finished. You can't do much to revive it and have to pull it out.
"They go for such a long period, and when the weather changes and gets cold, they almost die overnight with the cold temperatures."
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