- Types of Petunias
- Getting Started
- Care Tips
- Petunia Container Care: Growing Petunias In Pots
- Caring for Petunias in Pots
- How to Grow Petunias in Containers
- If you follow 7 of these Petunia Care Tips, you’ll be able to grow the most colorful and abundant petunia flowers in containers!
- Petunias are no doubt one of the most popular annual flowers and best to grow in containers. However, in warmer areas (considerably USDA Zones 9-11) they are tender perennials. Heat tolerant and easy to grow, petunias have some requirements. Here’re some petunia care tips you need to follow to grow the best petunias in containers!
- 1. Soak in sun
- 2. Watering is essential
- 3. Provide right soil
- 4. Fertilize for prolific blooms
- 5. Pinching should be done
- 6. Deadheading is must
- 7. Look at pest
- Growing Petunias
- Petunia Not Blooming: How To Fix Petunia Plant With No Flowers
- Reasons for Petunia Not Blooming
- How to Make Petunias Bloom Later
- One More Summer Sizzler — Mexican Petunia
- How to Make Petunias Last Longer
- Save the Seeds
- General Petunia Care
If you’re looking for a way to add quick curb appeal to your house, try planting petunias in your front yard, window boxes, or hanging baskets. They’ll bloom from early spring through early fall and pair perfectly with other annuals and perennials.
Petunias are a perfect addition to any garden and also make great cut flowers.
Want a versatile plant that comes in an abundance of bright bold colors and can be used in all of your gardens, containers, and hanging baskets? Then petunias are your go-to gardening friend. Low maintenance and drought tolerant with a light, sweet fragrance – they’re beautiful, desirable, and irresistible to butterflies, hummingbirds, and gardeners alike.
Petunias aren’t what they used to be! When they first appeared in the 19th century, they were lanky plants with tiny flowers. First discovered in South America in the late 1700’s, these wild varieties quickly captured the imagination of gardeners and collectors, who transformed them into the garden petunias we know today.
Once introduced to Europe in the early 1800’s, gardeners began cross breeding them in search of the perfect petunia – a plant with large beautiful flowers in brilliant colors. They ended up creating a wide variety of garden petunias – some with exciting colors or fringed single flowers, others with large and sometimes double flowers. Since then, breeders and gardens all over the world, from Japan to Germany to the United States, have continued to make changes and improvements to the petunia.
Types of Petunias
There are many different varieties of petunias which you can mix and match effortlessly to create the look that fits your style. Trailing petunias are a gardening essential, creating waves of color cascading over the edges of window boxes, hanging baskets, and containers. Spreading varieties are ideal ground covers, and compact varieties are great for edging garden borders.
Petunias are bright, lively and extremely easy to grow.
Grandiflora is the most popular variety of petunia, with large single or double flowers that form mounds of colorful solid, striped, or variegated blooms. Grandiflora prefer cool temperatures – in high heat, stems will stretch. Pair with sweet alyssum, portulaca and ivy-leaved geraniums in mass plantings, containers, or window boxes.
Multiflora varieties are compact plants that bloom prolifically all season, even during very hot or very wet spells. With single or double flowers in hues ranging from white and yellow to pink, crimson, and purple, they deliver a colorful display even when other plants struggle.
Millifloravarieties have petite 1” to 1 ½” blossoms that cover the plant with beautiful vibrant colors. These delicate petunias are great for fairy gardens and are scaled to be an accent plant for larger blooms, adding fullness and contrast in size and color. They require little maintenance and don’t need pruning to continue flowering.
Floribunda are basically an improved multiflora petunia, bred to have larger flowers that blooms earlier. They tolerate both hot and wet periods well and are a fantastic selection for mass plantings, hanging baskets, and containers.
Petunias are one of the most popular flowering annuals.
Spreading varieties are indispensable for anyone with a large area to cover in a short period of time. They spread quickly and bloom profusely, covered with so many blooms you may not see any foliage. At only 4 to 6 inches tall, they make a nice low-growing and fragrant ground cover, a vast improvement over a high maintenance lawn. They’ll also cascade over walls, hanging baskets, and containers for the finishing touch every gardener’s dreams of. With proper care they’re very resilient to heat and humidity. Plant with geraniums and salvia for a bright summer garden.
Calibrachoa is a close relative of the petunia introduced in the 1990’s. These petite petunia-like plants are miniatures in every aspect – flower, leaf and overall plant size. Trailing and mounding varieties are available, stay under 12” tall and bloom profusely, making a beautiful addition to mixed containers, hanging baskets, window boxes and as a carpet of color at garden’s edge.
If you have a nice sunny spot in your garden, petunias are the perfect pick – they’ll flourish in full sun, as long as they get some protection during from the midday heat and. They’ll also grow well in partial shade, although they won’t flower as much and stems will stretch more.
When buying petunias, there are a few things to keep in mind. Look for plants with both flowers and buds – this will help you see the bloom colors and also provide ongoing color after planting. Select plants with clean, green foliage without any dried leaves or spots. Avoid plants with soil that is water-logged.
Petunias are very easy to grow and will reward you with months of colorful blooms, asking little in return other than occasional watering. To get the most out of your petunias, you’ll also want to fertilize and prune them to get fuller with more blooms.
Petunias will bloom all summer long.
Petunias really only need to be watered by the rain but if the soil gets very dry or there is a prolonged dry period, they’ll need watering to keep the soil moist. If you’re growing petunias in a window box or other container the soil will dry out quicker so water as needed.
Your plants will grow and flower without feeding, but for more prolific blooms, fertilize once a month to encourage blooming. If you have double flowered petunias, increase the frequency to once every two weeks.
Most petunias, other than the milliflora and spreading petunias, should be pruned to ensure they produce new shoots and flowers. If you don’t prune your petunias they’ll grow out of shape by midsummer and bear fewer flowers.
Petunia Container Care: Growing Petunias In Pots
Planting petunias in containers is a fantastic way to showcase them. Whether in hanging baskets or containers on tables or a front porch, growing petunias in pots brings vibrant color throughout the summer to whatever area you choose. Keep reading to learn how to grow petunias in containers.
Caring for Petunias in Pots
Petunia container care is very easy. Soil in containers is prone to heating up and drying out much faster than soil in the garden, but petunias are particularly hot and dry hardy. This doesn’t mean you should neglect your petunias, but you should allow the soil to dry out completely between waterings.
Every few days, give them a long, slow drink. Wetting the flowers and foliage can promote disease, so water either from below or close to the surface of the soil. You don’t want to waterlog your roots either, though, so make sure your container has very good drainage.
Petunias are heavy feeders. Apply a slow release fertilizer at the time of planting, then follow up with a liquid fertilizer every week or two throughout the season.
Place your containers where they will receive full sun – six hours per day is good but eight is preferable for the fullest possible blooms.
How to Grow Petunias in Containers
You can purchase special trailing petunias, which will perform dramatically in containers. However, growing petunias in pots, regardless of their type, should not disappoint you, as long as you treat them right.
When planting petunias in containers, be sure not to crowd your plants, limiting yourself to three per 12-inch pot.
If your petunias start to flag or grow leggy, cut them back and fertilize them. They should branch out with vigor. Cut flowers for bouquets frequently to encourage new growth and remove dead flower heads as soon as they appear.
If you follow 7 of these Petunia Care Tips, you’ll be able to grow the most colorful and abundant petunia flowers in containers!
1. Soak in sun
To bloom abundantly, petunias require a good soak in the sun for at least 6 hours. They love warmth and sunlight. Keep your potted plants in a spot that receives full sun. *Those living in USDA Zones 9-11 and other warmer regions can provide shade in the afternoon.
2. Watering is essential
Petunias may recover from the underwatering shock, but overwatering is the main reason why container grown petunias die. This attractive flowering plant requires moderate watering and slightly moist soil during the day. Water regularly but let the soil to dry out between the watering spells to avoid root rot.
3. Provide right soil
For growing best petunias in pots, your growing medium must drain freely. A soil-less mix is right for this purpose. Either buy it or make your own, there are plenty of mix recipes available on the web.
4. Fertilize for prolific blooms
Petunias are greedy and needy plants when it comes to fertilizer. Either apply slow release fertilizer at the time of planting or feed them every other week using the diluted liquid fertilizer like 10-10-10. Additionally, application of compost on top of the surface can be made too. If your container grown petunias have lush foliage and less or no flowers, you may need to apply fertilizer that is low in nitrogen.
5. Pinching should be done
If you’ve bought petunia plants from a nursery or growing them from transplants, pinch off the top one inch from each stem and remove all flowers. If grown from seeds, baby petunias (multifloras and grandifloras), when they’re 6 inches tall, pinch them back a little to promote more vigorous side shoots. Milifloras (spreading petunias) don’t require this.
6. Deadheading is must
This is one of the essential petunia care tips you need to follow. Remove faded flowers so that the plant can concentrate its energy on producing more blooms. It’s also important to remove the seed developing portion below each flower.
7. Look at pest
Common garden pests, especially the aphids affect this beautiful flowering plant the most. So keep an eye on them, look on and under the leaves to identify the infestation.Check out some of the most effective natural ways to kill Aphids.
Many gardeners heap scorn on petunias, but I’ve always had a soft spot for these summer annuals which are available in a myriad of colours and forms including the perennial varieties sold as Million Bells or calibrochoa.
Petunias flower in red, purple, pink, yellow or white or the flowers may display combinations of these colours. They can be large or small flowered and some have doubled or ruffled blooms.
They can look gaudy, especially when grown as a mass of different colours but they are a fast and fool proof way to inject colour into your garden for summer. To minimise the riot of colour, choose colour mixes seedling varieties, or limit your planting to one or two colours that match the colour scheme in your garden. Boldly coloured petunias can also be used to add highlights to a green garden or enliven an outdoor entertaining area such as a barbecue area or around a swimming pool.
Apart from their brilliant colour, I also like petunias because they are tolerant of both heat and humidity. Even if they are hit by a hot dry gusty day, or a heavy storm, most bounce back without too much damage.
The best heatproof petunias are those with smaller flowers as these generally cope with both the high temperatures and the wet of summer.
Planting and growing tips
Petunias can be grown in the garden or in containers including hanging baskets. They need a sunny spot and grow best with regular watering and the addition of a liquid plant food every two to three weeks. Petunias need at least six hours of sun but full sun from morning to mid afternoon brings on the best performance from these plants.
You can buy petunias as seed, seedlings, small flowering pot plants (bloomers) or as flowering hanging baskets. Seed is planted from late winter to summer and seedlings are available from late winter. Petunias are frost sensitive so avoid planting petunias out in the garden until all threat of frost has past.
Expect plants to take around 12 weeks from seed sowing to flowering. Petunia seedlings may bloom in six to 10 weeks from planting into a pot, hanging basket or garden bed.
Give seedlings or small plants a good soaking in one of the seaweed solutions before planting to avoid transplant shock. Soaking also ensures the root balls are moist all the way through before they are planted out into the ground or a pot.
As the plants grow, ‘tip prune’ them to encourage branching growth. Tip pruning just means pinching out the soft tip growth using your fingers or secateurs to encourage the pair of shoots below the tip to branch out.
When flowering begins, regularly remove spent flowers to keep plants compact and producing more blooms. Petunias tend to die back towards the end of summer or into autumn. At this stage most plants can be removed to make room for autumn and winter plantings. Perennial forms can be cut back at this time and may regrow and re-flower in spring.
Protect seedlings from snails and slugs (use snail baits or regular inspections). Also check plants for caterpillars such as loopers or cabbage white butterfly larvae, which may feed on the flowers or leaves. Squash any you see or apply a garden spray to kill caterpillars such as Dipel or Yates Success. Always apply chemicals according to the label instructions.
Petunia Not Blooming: How To Fix Petunia Plant With No Flowers
A summer blooming favorite, many gardeners use petunias to add color to beds, borders and containers. Blooms are usually reliable until autumn, but what do you do if you have non blooming petunias? Learning how to make petunia bloom is fairly simple. Read more to find out what may have caused the petunia plant with no flowers.
Reasons for Petunia Not Blooming
Here are the most common reasons for a petunia plant not blooming:
When you find there are no blooms on petunias, the first thing is to check is the amount of light the non blooming petunias are receiving. Check at various times of day to see if the petunia plants with no flowers are getting direct sunshine. Petunias need full sun for the most optimum show of blossoms. The plant may bloom when it is lightly shaded for part of the day, but as a rule, a petunia not blooming can be because it does not get at least six hours of direct sun per day.
Move container planted petunias plants with no flowers into a sunny location. Ground planted, non blooming petunias can get more sun by thinning or trimming surrounding plants that may be shading them. If you’ve planted petunias in a shady spot that can’t be remedied, you may need to replant the petunia plant with no flowers.
If the lighting is correct and there are no blooms on petunias, perhaps they’re not getting enough water or fertilization. Petunias are somewhat drought tolerant, but will provide a more lush display when the soil is kept moist. Shake off excess water that is on the developing blooms of ground planted petunias; wet buds can rot away before blooming.
If you haven’t been feeding the petunia plant with no flowers, perhaps you should try this remedy. Many plants grown in nurseries are regularly fed with liquid fertilizer, but it only remains in the soil until it washes out from watering. It is possible that the petunias have been fertilized with a high nitrogen plant food, resulting in lush foliage, but non blooming petunias.
Change to a phosphorus heavy fertilizer, such as those labeled ‘bloom buster.’ Bone meal is also a good source of phosphorus. Phosphorus is the middle number in the 3-digit fertilizer ratio listed on the packaging. Choose a product labeled 10/30/10. A balanced fertilizer may be effective toward summer’s end if you’re hoping for a final performance from your petunias.
How to Make Petunias Bloom Later
Deadheading spent blooms will encourage the production of more flowers. If foliage begins to brown and die as summer wanes, clip it off right above a set of healthy leaves. Pinch back the center of the stalks.
Fertilize at this time with a balanced fertilizer, but one that has a high phosphorous number, such as 30/30/30. Enjoy the long lasting blooms of those petunias.
One More Summer Sizzler — Mexican Petunia
When you see a plant blooming its head off in a strip of compacted dirt between a parking lot and concrete wall in rainless, nasty July, you know it’s a tough customer. That’s just one of the reasons people love Mexican petunia.
As its name implies, Mexican petunia comes from south of the border. (No, I’m not talking about that tacky tourist park on the NC/SC line where Pedro sells sombreros the size of beach umbrellas.) Mexican petunia is not a real petunia, but its flower looks like one. The accepted botanical name is Ruellia brittoniana, but you’ll also see it called R. malacosperma and R. tweediana. Some folks say these are different plants and others say they’re all the same one. Grumpy says, “Who the h*** cares?” I mean, really. We’re busy people.
Cold-hardy in UDSA Zone 7 and southward, Mexican petunia grows 3 to 4 feet tall with attractive, purplish stems and narrow, lance-shaped leaves. Showy blue or purple flowers, beloved by butterflies and hummingbirds, appear from early summer through the fall. How showy are they? Well, when you find pots and pots of Mexican petunias in bloom in front of Home Depot and Lowe’s, you know know even non-gardeners find them fetching.
The Good, the Bad, and the Pretty
First, the good. Mexican petunia is incredibly easy to grow in full to partial sun. It’s one of the few perennials Grumpy knows that grows equally well in wet soil and dry soil. I often see it thriving in traffic islands, gas station plantings, and strips between sidewalks and curb where it gets absolutely no care. And as I mentioned before, butterflies and hummers covet it. Individual flowers last but one day, but there are always new flowers opening.
Now, the bad. The fact that this plant is a survivor means it can get out of hand. It forms large clumps by spreading roots that are hard to kill. And its exploding seed capsules scatter seed far and wide. In wet climates and unmanaged areas, it can be invasive. Indeed, the state of Florida considers it as such, although I hardly think it ranks up there with kudzu, popcorn tree, privet, and water hyacinth.
So should you still plant it? Yes, as long as you plant types that are not invasive. Fortunately, Grumpy knows of a few that are now available in garden centers and mail-order nurseries.
Here’s the first one. It’s a dwarf called ‘Katie.’ It grows about 10 inches high and 12 inches wide. It sets few seeds and is not an aggressive spreader. Large, blue-purple flowers appear from June until frost. This is a good one for massing as a ground cover. Niche Gardens is a good mail-order source.
A second Mexican petunia to consider is ‘Purple Showers.’ It looks a lot like the plant pictured up top, but has larger, deep purple flowers. Developed by the University of Florida, ‘Purple Showers’ is sterile, so it sets no seed. However, it still can spread by roots, so don’t plant it in wet soil. You can order this one from Avant Gardens. It’s also available at big-box stores.
Your third choice is to go native and plant a charming little species indigenous to the Midwest and South called Carolina wild petunia (R. caroliniensis), pictured above in my garden. It grows only a foot tall and blooms off and on all summer. It will spread by seed some, but not enough to be annoying. And it’s just as tough as Mexican petunia. I got mine from Jean in Tennessee, who’s a wonderful person despite being a die-hard Volunteer fan (Oh, the shame!). You can order it from Woodlanders. It does well for me in sun and light shade and is more cold-hardy than its Mexican cousin.
Don’t Forget the Tomato Contest!
Image zoom Grumpy’s Big Fat Tomato Contest
I know it’s been a tough summer for growing tomatoes, but Grumpy believes in you! So be sure to enter Grumpy’s Big Fat Tomato Contest before August 31. Prizes will be awarded for:
- Biggest Tomato
- Prettiest Tomato
- Weirdest Tomato
- Mr. Tomato Head
It’s your chance to achieve tomato immortality.
About three years ago we were given some mystery seeds by a friend. They were from a “dark green plant with blue crepe paper looking blooms”. I planted them in a corner of the garden next to our garage. Within a relatively short period of time, we had a dark green serrated leaf plant that eventually bloomed with bright blue tubular flowers. It froze back in the winter reappearing in the spring. AND it spread but we found it was easy to pull out the miniature self-seeded plants.
I tried to identify this plant without any luck. Sunset Western Garden Book was read from cover to cover, I asked other gardeners who toured our garden and basically had given up the quest. Then last week during a tour at High Hand Nursery in Loomis with the Vaca Valley Garden Club, I spotted our plant. It is a ‘Ruellia brittoncana’ or Mexican petunia. Finally the mystery plant was identified and had a name.
In doing some research, this plant is native to Mexico and easy to grow in dry or wet soil conditions. They are perennial shrubs that grow about 3 feet tall and 4 feet wide. There are some dwarf varieties available such as ‘Katie’, which grows to 10 inches in height. With little care these plants produce flowers in white, purple or many shades of blue. They resemble the petunia flower we are familiar with, but the two plants are NOT related. Butterflies and hummingbirds are attracted to the colorful blooms, which makes the plants popular with backyard gardeners.
Gardeners either love Ruellia or dislike it due to its invasive nature. There is a sterile version that will not re-seed called ‘Purple Showers’; the flowers are deep purple. Though it will not re-seed, it can spread by its roots if grown in wet soil. Sometimes called desert petunias, the more sun they receive the more blooms they produce. You can propagate Mexican petunias by cuttings, seeds or division.
Plant in the early spring and once established you will have blooms throughout the summer into fall. The plant is hardy enough to survive long periods without water, although young plants need regular watering. They adapt easily and grow well in containers, provided they receive sun. And the best news is Ruellia brittoncana is highly resistant to most disease and pests.
The stunning color of petunias can be the crowning glory of your flower garden. It’s a shame they can’t be permanent. How long can you expect to enjoy these classic summer plants?
When you’re wondering how long do petunias last, you might be considering two different things. How long do the plants themselves actually live for, or perhaps you want to know how long the flowers last once your petunias bloom?
To tackle the first part of the question, petunias can live for 2 or 3 years but generally behave as annuals because they can’t survive the freezing temperatures of the winter. More on that below. For the second part, it’s difficult to really put a timeline on each individual blossom. They’re not particularly long-lived, but the plant puts out so many of them that you may not really notice.
How to Make Petunias Last Longer
When you want your outside petunias to live longer than a single season, you have to protect them from the cold. The most effective way to do this is to bring them indoors. Now, if you plan ahead, you can make this a lot simpler by planting them in portable containers to begin with. If they are already growing in the ground, you may have to carefully dig them up and repot them in the fall before the chilly weather triggers them to die back.
Either way, you can treat them like houseplants until spring, extending the life of your petunias for an extra year or two. But as I mentioned, they do have a natural limit to their lives and will eventually die back for good after perhaps 3 years.
Now if you aren’t looking for overall plant lifespan, you can have your petunias bloom longer with a few simple tricks. The obvious one is to give your plants lots of proper care (more on that below). You can also be quick to pluck off dead or dying flowers to spur the plant to put out more buds. This is called “deadheading” and is a pretty common task to get a flowering plant to do more blooming.
Save the Seeds
Saving the seed from your petunias isn’t quite the same as getting them to live longer, but it will mean that you can continue to plant new petunias each spring without having to completely start from scratch with purchased seed.
Not only do you save a little money by not buying new seeds, you can develop your own personal strain of petunias when you choose only the plants that thrive best in your garden.
Choose a plant that is doing very well, with flowers in your favorite color. Don’t do any deadheading to it, and let the dying flowers set their seed pods. Once the blooms drop off, you’ll see a little bulb develop in their place. At this point, watch your petunia regularly or you might lose your seeds.
Eventually, that little green bulb will turn brown and start to crack open. As soon as you see it split, it’s time to harvest your petunia seeds. Carefully snip off the pods and get ready to dry them.
Lay the pods out on a piece of paper towel, and leave them to finish drying in a cool, dry spot that is also out of the sun. Air drying is what you are after, not baking in heat. Give them a week, and when you can hear the seeds rattling around inside, they are ready to break open.
Gently crush the pods, and pick the seeds out of the debris. Store in a paper envelope where they will stay dry. Next year, you can plant them and keep your petunias going.
Be aware though that many of today’s petunias are hybrids, and may not “breed true.” That just means that your next generation of flowers may not look exactly like the originals. But that would be the case with any plants as these are seeds rather than clones or cuttings. Expect some natural variation.
General Petunia Care
Overall, the best way to have your petunias last as long as possible is to give the best care you can. The most important thing you can do for petunias is give them plenty of sun, without really letting them get too hot. They’re not cacti after all.
They should be watered whenever the soil starts to feel dry to the touch. Unless you live in a particularly dry climate, or are just having a bit of a drought, you probably won’t have to do many watering chores as the regular rainfall should be enough for petunias.
All of those luscious flowers can come at a price. Petunias are very “heavy feeders,” requiring plenty of nutrients in the soil to keep them healthy. While they are outside, plan to give them a dose of compost or aged manure once a month over the summer season.
For petunias that you have moved indoors, the same thing applies. Use a standard houseplant fertilizer that is geared towards flowering plants, and feed your petunias weekly.
Though they can be similar, there are several different varieties of petunias on the market you can choose from.
- Grandiflora petunias
- Multiflora petunias
- Spreading (Wave) petunias
Longevity-wise, it won’t matter which one you grow. They all have the same life span. The differences are about flower size and plant behavior.
Grandifloras are the most common, with their usual big flowers and plants that grow upright from 8 to 12 inches high. The multiflora petunias are more compact in shape, and the flowers are smaller.
You can also get spreading petunias for those spots where you want to really cover your space with color. Only 6 inches high, these ones can spread out several feet, still putting out flowers all the way.
No matter which variety appeals to you, there will be a whole rainbow of colors you can work with, in either solid hues or bi-color.
Unlike some plants that can easily outlive a person, petunias are simply not going to last forever. A little extra work and attention can make them last longer, and add a few more colorful years to your garden space.
47shares How Long Do Petunias Last? (The Flowers and the Plants Themselves) was last modified: July 26th, 2019 by The Practical Planter