How to Plant, Grow, and Care for Supertunias

There are many petunia hybrids on the market these days, but few can compete with Supertunias®. These epic flowers grow quickly and cover your garden spaces with almost endless blooms. 

There are several cultivars to choose from, each with its own colors and growth habits. All of them are incredibly easy to grow and vigorous. Pair them with annuals such as verbena, amaranth, and salvias to create beautiful landscape designs. 

Even if you’re looking for flowers to fill your favorite containers or something to cover your entire yard, Supertunias® will do the job. Let’s dive into how to grow and care for these stunning bloomers. 

What Is It?

Supertunias® are hybrid petunias created by the company Proven Winners in 2006. They followed the popularity of Wave petunias and quickly became another beloved hybrid. 

Some varieties grow as trailing flowers while others have more of a mounding growing habit. They come in a variety of sizes and colors, with blooms that last all year long. 

Grow them in containers, garden beds, or hanging baskets like these. They’ll pair great with other flowers like verbenas and geraniums. 

Characteristics

These amazing hybrids grow great as annuals in a variety of climates. However, if you live in a warm climate, try to grow them as tender perennials.

Most Supertunias® grow to be under a foot tall. Some, like the Vista cultivars, can grow to be almost 2 feet tall. Most Supertunias® have stems with single flowers that grow at a remarkably fast rate. 

Depending on the variety, you can find some with tiny, compact flowers or medium-sized blooms. They start producing flowers in early summer and keep blooming until early fall. The best part about Supertunias®, other than their beauty, is their pollinator-attracting potential. Bees flock to the colorful flowers all season long.

Native Area

These hybrids were created by the company Proven Winners. For decades, plant breeders around the world have been working with petunia varieties to create resilient and easy-to-grow hybrids. 

The original petunias came from wild South American flowers. There are about 35 species and over 1,000 varieties of the petunia. These plants grow in habitats that include the rolling hills and plains of Argentina, Brazil, and Uruguay. 

These plants need to grow in zones 9 through 11 to be perennials. They don’t tolerate the cold and prefer climates with plenty of sun. 

Planting

Plant these beautiful hybrids in spaces with full sun and well-drained soil. They’ll grow well in containers or outdoor garden beds. Be mindful that these fast-growing flowers will take up over 3 feet of space in no time. If you let them go, you’ll have carpets of brilliant petals covering your yard. 

Plant your flowers outdoors in early spring, or start them inside and transplant them later. Give your plants plenty of space so they don’t compete for nutrients and water. 

Try planting them around other ornamental plants or structures for a colorful border crop. They also make colorful groundcover. 

Transplanting

If you have seedlings or starters, you can transplant them into the ground in late spring. Wait a few weeks after the last threat of frost has passed. 

Carefully remove your plants from their containers. Dig a hole that’s twice as wide as the original containers. The depth should be as shallow as the root ball. 

Place your plants in the hole and gently cover them up to their base in the soil. Water them well and keep the soil moist throughout the growing season. 

Growing From Seed

Supertunias® are incredibly easy to grow from seed. First, check the Old Farmer’s Almanac to find out what day is your last frost. Start your seeds indoors 10 to 12 weeks before this date. 

Fill growing trays with loose, well-drained potting soil. Add a very small amount of slow-release fertilizer to boost the nutrients before planting. Once your soil temperature is above 68°F (20°C), plant three seeds per cell on the surface of the soil. Gently press them so the soil barely covers them. Use a heat mat if the area you’re growing in is cool. Employ a grow light, as seeds need light to germinate.

Water your trays to keep the soil moist. Wait two to four weeks for your seeds to germinate. When your seedlings emerge, thin out the weakest ones to one plant. If you’re starting them in larger containers, space them out to 1 every 8 to 10 inches. 

How to Grow

Supertunias® are incredibly easy to grow. They’ll grow vigorously in almost any container. They’re also very easy to maintain. So, if you’re a beginning gardener, this special flower should be on your radar. 

Light

Like other petunia varieties, these hybrids need lots of direct sunlight. Plant them in an area that gets over 6 hours of sunlight. Avoid areas with extensive shade from tall trees or large buildings.  

If you start them indoors, grow them near a south-facing window. If you live in a cold climate, you can place your trays under grow lights. These lights give your plants all the light they need to thrive. 

Water

Supertunias® love a lot of water. They’ll flourish if their soil is nice and moist throughout the growing season. Never let the soil dry out or your flowers will lose their brilliance. 

Water them in the morning to avoid moisture buildup in the leaves and flowers. Try to stick to watering the base of the plant. 

Although the soil should be moist, avoid watering too much. Your plants could experience serious growing problems if their soil is soggy. 

Soil

Start with a standard soil mixture that’s well-drained and fluffy. Try to use soil that has a neutral pH or is slightly acidic. You can amend it with a healthy dose of organic compost to raise the nutrient level before planting. 

If you notice your soil is absorbing too much moisture and not draining well, consider transplanting your plants to a better location. These plants can handle being moved better than many flower varieties. 

Temperature and Humidity

The best temperature to grow your flowers in is between 60 and 75°F (16-24°C). They will show signs of temperature shock in temperatures below 55°F (13°C). 

If you live in cold regions, you’ll have to either let your plants die naturally or bring them in when the first frosts arrive in the fall. Cold weather will quickly kill your plants, so monitor the weather carefully if you want to grow them late into the season. 

You can grow them in almost any level of humidity. Even in dry deserts like inland California, you’ll be able to get these flowers to flourish. Simply keep up with their watering schedule and enjoy. 

Fertilizing

Supertunias® are not particularly heavy feeders. However, they will benefit from the occasional feeding as they grow. Start with a balanced fertilizer before planting. A slow release organic fertilizer will do the job. 

As they grow, give them a feeding with a liquid fertilizer diluted to half or quarter strength whenever their flowers are looking dull. Generally, you can use a liquid fertilizer every 3 weeks during the peak summer months. Make sure you never over feed them and always follow your product’s directions. 

Maintenance

The best way to maintain petunias like these is to prune them whenever they start to look disheveled. Use disinfected pruners or shears to clip away yellow, leggy, or unhealthy-looking stems. 

After your flowers bloom, there is no need to deadhead them to encourage new blooms and growth. This is because these petunias are self-cleaning.

Propagation

The easiest way to propagate these hybrids is by doing stem cuttings. This is super easy, even if you’re a novice gardener. 

Start by taking a cutting that’s 6 inches long. Leave a few leaves on the tip but remove leaves towards the bottom incision. 

You can roll the stem in rooting hormone and plant the cutting in moist, well-drained soil. Water it thoroughly and wait for vigorous new growth before transplanting your cutting. 

Popular Varieties

There are several beautiful varieties of Supertunias® to grow. Each one has its own special growing habit, size, and color pattern. Find one you love, or try growing as many as you can. 

‘Supertunia® Vista Snowdrift™’

This spreading variety grows up to 24 inches tall. Some individuals will be up to 3 feet wide and fill containers and garden beds. This variety has bright white flowers that look almost cartoonish because they’re so beautiful. 

‘Supertunia® Really Red’

If you love red flowers, you’ll fall in love with this variety. It grows in trailing and mounding patterns and is super easy to care for. Some can trail close to 3 feet, which makes it a great landscape variety. 

‘Supertunia® Giant Pink’

This beautiful variety has large and stunning pink flowers that are hard to ignore. They almost look like pink trumpets in your garden. If you want the ultimate pollinator attractor, this flower is it!

‘Supertunia® Royal Velvet®’

This lovely variety produces violet to purple flowers that can get quite large. It grows vigorously and will quickly cover your yard or garden in purple. 

Common Problems

These hybrid petunias can sometimes experience leggy growth and wilting. If you notice your stems are growing too long, it’s probably because the plant needs more light. Plants become leggy if they’re growing toward a light source. Remove leggy growth and deadhead the flowers after they bloom. 

Wilted leaves and foliage are usually a sign of too little or too much water. Increase or decrease your watering and watch for changes in the plant’s structure. 

Pests

As with any other garden plant, pests can be an issue. Slugs, snails, and aphids are usually the most common enemies to look out for. Watch for signs of holes in the leaves or trails of sticky honeydew. You can take out snails at night by hand, use organic bait, or set a beer trap.

Aphids can be persistent on Supertunias® so keep a watchful eye for them. They’re very tiny and hard to spot. They’ll feed on the sap of your plants and cause them to lose their shape and vigour. 

If you see a pest infestation, remove them by hand or use an organic insecticide like neem oil. Cultivate a garden ecosystem with beneficial insects like wasps and ladybugs. These critters, along with small birds, will consume the pests before they become a problem. 

Diseases

The most common diseases include stem and root rots. These rots occur when the soil is too moist. Fungus ends up attacking the roots or stems of your plants and decomposes the plant tissue. 

Even if you catch these diseases early, there’s not much you can do to save your flowers. You can try to repot them, removing the rotten roots in the process. As long as portions of the roots are still white, you may be able to coax yours back from death. Remove diseased plants and throw them out in the garbage immediately. Treat the soil with an organic fungicide before planting anything else. 

The only way to prevent rots is by watching your watering. Avoid overly soaking the soil and give your garden time to drain its moisture between soakings.