Knowing how to care for petunias in hanging baskets can make the difference between mediocre plants and stunning displays. If you want to impress your neighbours, read on to learn everything you need to know about petunia hanging basket care.
As a general rule, petunias will last and bloom all summer long in a hanging basket so long as they have the proper care. Give your petunias adequate water, sunlight, fertilizer and tend to pruning, deadheading, and pest control, and your petunias will bloom continuously until the first frost.
We’re going to provide you with all the information you need to grow envious petunia hanging baskets through the entire growing season. So keep reading to find out how.
Check your hardiness zone
Petunia plants are classified as tender perennials in USDA zones 9-11. In those warmer zones, petunias will come back year after year. However, petunias are grown as half-hardy annuals that die back after a hard frost in most regions.
Petunias originate from South America, so they do prefer a warm climate. That doesn’t mean that you can’t grow them in zones below 9, it just means that you will need to plant fresh petunias every year. So go ahead and plant petunias in your garden beds, window boxes, or hanging baskets so that you can enjoy their wonderful, large flowers all summer.
Provide at least 6 hours of sunlight per day
Petunia flowers require at least 6 hours of direct sunlight a day.
To encourage the best bloom, place your petunia hanging basket in a spot that receives full sun for at least half of the day. Too much shade will discourage blooming.
Set a Daily watering schedule
The most important step to petunia hanging basket care is proper watering. Petunias in baskets require regular watering at least once a day. In addition, they may need to be watered twice a day in hotter regions or warmer weather.
You will want to water petunias deeply to avoid growing plants with shallow roots.
Check the top inch of soil before watering to ensure the soil is dry. Frequent unnecessary waterings can lead to a fungal disease like root rot, so avoid providing too much water.
fertilize and feed petunias Every Week
Petunias are heavy feeders and, when planted in a container, will very quickly deplete the nutrients in the soil.
It’s a good idea to add a slow-release fertilizer at the soil surface after planting or when you bring your containers home. A slow-release balanced fertilizer will provide nutrients over many weeks.
Liquid fertilizer will work as well, but you will lose much of the fertilizer while watering as excess will drain out of the bottom of the pot.
Choose a Potting Soil with lots of organic matter
The correct soil type is essential for healthy petunia plants that flower throughout the season.
The soil should have lots of organic matter, with additions like vermiculite for water retention, peat, and choir for good drainage.
It’s best to purchase soil specifically for potted plants like pro-mix.
Choose A sturdy basket with good drainage
When choosing a basket for your petunias, you need to ensure the pot is big and sturdy enough (at least 10 inches) and that it has adequate drainage holes.
You can plant your petunias in almost any vessel and they will grow, but small pots under 10 inches will dry out incredibly fast and will require constant monitoring during the summer.
For additional drainage, it is a good idea to add an inch of small gravel or rocks to the bottom of the basket. Adding small stones or gravel is a great way to ensure excellent drainage.
- Related: If you’re handy try making these easy pyramid-style hanging baskets. The plans are free, and the baskets look quite spiffy!
Plant milliflora and multiflora petunias for Best displays
The best petunia varieties for your hanging baskets are milliflora and multiflora petunias. These two types of petunias have trailing growth habits and bloom intensely. The flowers will drape and hang over the sides of hanging baskets and create a very dramatic display. They also hold up better in heavy rain and generally inclement weather.
For extraordinary hanging baskets, I recommend any of the wave petunias.
With that said, you can also plant other petunias in hanging baskets. Some of the bushier petunias will create mounds of flowers that do not hang but have a neat growing habit that you may prefer.
It’s important to note that Grandiflora petunias can get spindly mid-summer, especially in hanging baskets, and will require heavy pruning to encourage more blooms. In addition, the Grandiflora petunias require a bit more care (like deadheading during the season), so I try to avoid planting them in hanging baskets for those reasons.
Plant the correct number of petunias for your basket size
The general rule for standard petunias is to divide the size of your basket by two, and that is the number of petunias required. For example, a 10-inch basket would require 5; a 14-inch basket needs at least 7.
The exception is the large flowering wave petunias for wave petunias plant, approximately 3 per 10-inch basket.
If you’re planting your flower baskets, remember most garden centers start their petunia baskets in early spring, so they have big beautiful displays bursting with flowers at the start of the growing season.
If you buy your petunias for your baskets in late spring, the flowers will be just getting started, and your baskets may look sparse. Do not let this bother you. Those plants will fill in just fine, and that basket will be beautiful in a few weeks.
Our Best Petunia Buying Tip!
Choose a Sheltered spot with plenty of sun
It’s a good idea to pick a site sheltered from strong winds. Strong winds can do a great deal of damage to your petunia hanging baskets.
You also want to choose a site that has adequate sunlight. For example, placing baskets on shaded porches can cause the flowers to be less prolific.
And lastly, be sure to hang those baskets high enough if deer are a problem in your area. Deers love to eat petunias, but raising them out of reach is a great way to keep your flowers from being a deer’s lunch.
deadhead regularly and prune in late summer
How do you keep hanging petunias looking good? Deadhead and prune your petunias regularly to keep them looking good all season. For big bushy heavy flowered petunia baskets, the recommendation is to pinch out the growing tips when the plants are about 6 inches tall. Pinching will encourage branching and bushy growth.
You can even pinch again after the first flower flush for even more flowers!
If plants become leggy and stop blooming during the hottest days of summer, you can sheer them back add fertilizer and water to promote new growth.
Removing dead flowers and old flowers from petunia plants will also help encourage new blooms.
Learn More: For more info, check out our full article on deadheading petunias.
Manage Petunia Pests as soon as you can
Petunias are generally carefree and are not bothered by many insect pests, but several species of beetles can find their way to your baskets and cause damage.
HOW TO IDENTIFY Beetles That Damage Petunias
Asiatic garden beetles (madera castanea) are 1/3 inch long reddish-brown beetles that feed on your petunias only at night. The larvae are C-shaped grayish grubs with brown heads that eat plant roots.
Spotted cucumber beetles are slender 1/2 long greenish-yellow bugs with 12 prominent spots on their backs. It will feast on buds, petals, and leaves.
Colorado potato beetles are 3/8 of an inch long with black and yellow stripes. Their grubs are plump and red. These critters will eat the foliage of petunias.
Flea beetles are small black beetles that will chew hundreds of tiny holes in the leaves and flowers.
Beetle control methods
All beetles are controlled the same way: Where possible, pick the beetles off the petunias and crush or drop them into a bucket of soapy water. This works incredibly well for light infestations.
If you have a heavy infestation of beetles, you may spray plants with a solution of pyrethrum and isopropyl alcohol, mixing 1 tablespoon of alcohol per 2 cups of diluted pyrethrum mixture. Apply every 3-5 days over three weeks or until the problem is corrected.
BAD BUG BEGONE!
Are harmful insects running your gardening season?
Our guide to organic pest control methods offers practical solutions for dealing with common garden pests without using harmful chemicals. With step-by-step instructions and easy-to-follow tips, you’ll learn how to create a pest-resistant garden that is safe for your family and the environment. A great on-hand resource for any gardener!
A must-have resource for Gardeners
Our digital e-book is for you if you’re a home gardener passionate about growing healthy, pesticide-free plants! Over 100 pages of organic pest management information are perfect for beginner gardeners and pros alike.
ManagE petunia Diseases as they appear
Petunias can be affected by several diseases. Fungal diseases like stem rot and viral infections such as mosaic, ringspot, aster yellow, and beet curly top are some problems that can develop in petunias.
PETUNIA Stem Rot SYMPTOMS & IDENTIFICATION
Stem rot will present when you see the stems of infected plants rot at the base and collapse and die. Preventative measures are always the defense against fungal diseases. Plant petunias in well-draining soil, avoid overwatering, and not crowd the plants.
Stem Rot Control Method
Control Method: If your petunias are infected with stem rot, you must remove the plants and the soil and destroy them. Do not add this material to your compost pile or risk the disease spreading through the rest of your garden.
PETUNIA Virus Diseases SYMPTOMS & IDENTIFICATION
Virus diseases like ring spots will show up in spindly plants with stunted shoots and yellow leaves. In addition, leaves may be marked with ring spots, lines, mottling, and dead spots.
Petunias that suddenly appear with curled or distorted leaves may be infected with the virus that causes curly beet top.
Aster yellows cause leaves that are yellow and spindly along with stunted growth. In addition, young plants are that are infected show yellowing along leaf veins.
Virus disease control method
There is no cure for virus-infected planted. Remove the plants and the soil and destroy them. You will also want to heavily sanitize the basket if you use it in future seasons. You will need to sanitize every bit of the hanging basket, including the hanger.
Also, disinfect any tools you used while destroying the plants or moving the soil.
Gardening Tool DIY Disinfectant
Looking For More Summer Flower Inspiration?
We hope you learned everything you need to know about petunia hanging basket care. We have so much more information to share with you about flower gardening, though, so if you’re looking for inspiration or even ideas, check out these posts!