Originating from South America but carrying a beautiful French name, petunias are undoubtedly the ladies of the garden.
Fast-growing and flowering with gorgeous, vividly colored blooms that enchant the eye and mesmerize any onlooker, petunias are a must-have in any well-tended garden.
This is your one-stop guide on how to plant petunias, how to care for them, but also your guide on understanding these beautiful flowers better.
Where do they come from, what types of petunias can you grow in your garden, and what do they symbolize in the language of flowers? All you need to know about petunias in an exhaustive guide.
- Petunia Flower Card
- How to Grow Petunias
- Petunia care – Diseases and Pests
- How to Deadhead Petunias
- Where Do Petunias Come From?
- Types of Petunias
- Petunia Meaning – What Do They Symbolize?
- Are You Ready to Start Growing Petunias?
Petunia Flower Card
Origin: South America
Common name: Petunia
Scientific name: Petunia Atkinsiana
Rank / Species: Hybrid
Height: 12 to 18 inches
Blooms: Single and double blooms that can reach 1 to 3 inches in diameter.
Colors: A wide variety of colors that include pink, white, purple, and black. Some petunias are spotted.
Foliage: Petunia leaves are pale to deep green and have a sticky and hairy texture.
How to Grow Petunias
Learning how to grow petunias depends entirely on the type or types you are planning on planting in your garden.
The reason is that not all species of petunias react the same, nor do they have the same requirements. However, here are some general tips that are useful for every Petunia type you are growing.
Best Petunia Seeds
Passionate breeders all over the world come up with new types of petunias every single year. Therefore, it can be quite tricky to choose which ones will be best for your garden.
But we can help you there. As a rule of thumb, these are the best ones you can grow:
- Supertunia Silver – the bloom in itself is almost white and it has a lavender core and veins. The color contrast makes it outstandingly beautiful.
- Blue Spark Cascadia – violet flowers with a dark purple core that also give off a sweet scent.
- Prism Sunshine – as the name suggests, it produces large, buttery yellow flowers that have a very good weather tolerance.
Growing Petunias from Seed
Petunias are some of the easiest annual flowers to grow in your garden, either directly in the soil or in containers. They can withstand almost any climate and are the care is pretty straightforward. Below you can find the most important things to consider when growing petunias in your garden.
You should be aware that petunias are not fans of frost, but they can grow in lower temperatures in case you live in that kind of climate. They also don’t enjoy extremely hot weather which will cause them to stop flowering until the temperature has dropped a few degrees.
As a rule of thumb, most types of petunias enjoy the sunlight as much as possible. However, if the temperature gets too hot or the sun is too scorching, make sure to give them some shade as well. This will make them bloom better as the plants will be refreshed.
Petunias thrive in a slightly acidic soil that has been drained very well. The soil has to be very fertile and well-fed, otherwise, they will not bloom at all.
When it comes to water, the situation could become a little tricky, but only until you get the hang of it. The reason is that petunias love well-watered soils but don’t really like it when there’s too much of it.
Therefore, you have to strike the perfect balance with these little beauties. Water them once a week, as deeply as you can, and allow them to nourish off of that.
You can also use fertilizer to give your petunias a boost. They thrive on balanced fertilizers such as 12-12-12.
In the month of July, you can use liquid fertilizer on your petunias but no more than once every two weeks. This is definitely the case for garden petunias that tend to spread and need all the nourishment they can get.
Petunia care – Diseases and Pests
The good news for every gardener who is in love with petunias is that they don’t require a lot of attention when it comes to diseases and pests. However, here are a few things that can happen to these flowers and what you can do about them.
- They can grow soft rot or gray mold – there is no way to combat this. Therefore, you should choose types of petunias that are resistant to rot and mold in the first place to make your job easier.
- Aphids – hose your petunias down using a lot of water.
- Budworm caterpillars – these little green caterpillars come out in July to feast on the flowers. You can leave them be. The insects usually disappear on their own later the same month.
How to Deadhead Petunias
If you have your eye set on some of the newer types of petunias on the market, you might have noticed that the instructions say you won’t need to deadhead them.
However, seasoned gardeners -who know their way with these gorgeous flowers- advise it’s best to deadhead them anyway. This practice encourages them to bloom better instead of just producing seeds and makes them look far more beautiful.
So how do you do it?
- Do a visual or manual inspection of your petunia rows. Locate any dead or withered flowers. Keep in mind that some of them could still hold seeds even though they appear withered.
- Using shears or pruning scissors, cut the withered petunias right at the stem. This means beneath the bloom. You have to remove all parts of the flower itself, but you can leave some of the stem intact.
- If the entire plant appears to have overgrown or to be leggy, you can reduce its size, but no more than half.
Tips – don’t deadhead your petunias more than once a week. Allow the plants a bit of time to recover from the trimming. The best time to deadhead your petunias is in mid-summer. The flowers will grow back more luxuriously and never cease to bloom.
Where Do Petunias Come From?
Despite the fact that today petunias are considered to be some of the most common garden flowers you will ever see, this has not always been the case with these beautiful blooms. In fact, petunias have a long and tumultuous history.
Given the fact that they belong to the Solanaceae family, petunias are closely related to the very benign potato, tomato, gooseberry, and chili pepper. But they are also cousins of the not so friendly tobacco and the deadly nightshade.
Petunias were discovered in South America in the 16th century, during the reign of Queen Elizabeth I. In the native language of the local tribe, the flowers were called petun which roughly translated to a worthless tobacco plant.
This idea plus the fact that 16-century colonists thought petunias to be quite unattractive made them not take any samples back to Spain with them.
It was only after three hundred years that two separate explorers, one Scottish and one sent by the French King to South America, found petunias once more and sent samples to their countries in Europe.
Not only that, but one of them found a whole new species of petunias – Petunia the Violacea – that was purple.
In the late 1800s, breeders from Europe, America, and Japan became widely interested in the flower and started crossing its samples in the hope of getting more colors.
This was how we got the petunias we know and love today which are considered to be hybrids of the original South American ones.
It is also worth mentioning here for those interested in growing petunias that the process of crossing them has not stopped since the 1800s. It is still going on today, with specialists all over the world trying to invent the perfect petunias.
As a result, there are now over 100 types of petunias. For example, in 1983, a whole new class was created, which was called Floribunda.
In 1995, the world was introduced to a brand new petunia called the Purple Wave. This is something you will need to take into account when choosing what you want to grow. Which brings us to the main types of Petunias.
Types of Petunias
If you’re new to the world of petunias, the first thing you need to know is that they are divided into four categories.
It is out of those four subgroups that you can choose the kind you like the most or that will fit your garden best. Here is the classification along with some examples.
They are known for producing either single or double flowers that can grow up to 5cm in diameter. You have probably already come in contact with them because these are the most common types of petunias available.
Grandifloras are perfect for window boxes or hanging pots because they tend to cascade beautifully as they grow and expand. Here are some examples belonging to this subgroup.
A lot more compact than the cascading grandi, multiflora petunias grow smaller flowers that reach 1 to 1 ½ inches in diameter.
They are perfect for every type of garden, but you will benefit from their small, beautiful flowers mostly if you plant them in tight containers. In this way, you can see them closely together.
Multiflora petunias will need to be deadheaded often to encourage production and blooming. Here are some species you can grow yourself.
The blooms come in at around 2 inches in diameter and are an absolute crowd favorite.
The reason is that this subspecies of petunias produces very bright and colorful blooms that are usually used as a color accent in gardens that need a little happiness.
Apart from that, Milliflora petunias can withstand wind and rain very well, making them easy to grow in every climate. Examples include the following:
Wave Petunias are also called spreading or ground cover petunias. They are not very tall, coming in at only 6 inches in height, but they can spread very widely, hence their name. In one single growing season, your wave petunias can cover 4 feet.
However, they will need a lot of water and weekly fertilization to keep up with all that spreading. Since they tend to grow long, you can allow them to cover the ground of your garden or you can plant them in pots and have them hanging in a cascade. Here are some examples.
- Shock Wave
- Easy Wave
Petunia Meaning – What Do They Symbolize?
It’s no secret that every flower has a special meaning. However, while you might be familiar with the more popular ones – red roses mean love, snowdrops mean purity, and yellow roses are a sign of jealousy – you might not be aware of the meaning of petunias.
When it comes to their symbolism, many agree that it has changed over the centuries, just like petunias themselves have changed.
As a result, years and years ago, petunias symbolized resentment and anger. This could be a remnant of the fact that, when they were discovered, European colonists didn’t take a liking to them and refused to bring them back to their native England and Spain.
However, in more modern times, ever since the world has rediscovered petunias and just how beautiful they are, their symbolism has changed as well.
As a result, growing petunias or gifting them to someone today symbolizes your desire to spend time with them because their company is soothing and calming to you. At the same time, petunias stand for not losing hope.
Are You Ready to Start Growing Petunias?
Petunias are some of the easiest flowers to grow in your garden, either directly in the soil or in containers. They can withstand almost any climate and don’t fall prey to pests and diseases that easily.
When pruned and deadheaded correctly, as you have seen in this exhaustive guide, petunias produce beautiful, vividly colored flowers that will be the delight of your garden. So, are you ready to start growing petunias?
From a simple penchant for yellow flowers as a child to becoming a full-time gardener, nature advocate, and garden designer, I am extremely happy to finally have a platform for me to successfully spread knowledge and expertise in the garden. After graduation, I took many courses related to garden design to feed myself with more knowledge and expertise other than what I learned from my mom growing up while also joining as many garden design competitions locally. For any garden design inquiries, I’m your designer!