Coral Knock Out® Rose

Rosa 'Radral' (PP#19,803)

Coral Knock Out® Rose

Rosa 'Radral' (PP#19,803)


How are the heights measured?

All tree, and nothin' but the tree! We measure from the top of the soil to the top of the tree; the height of the container or the root system is never included in our measurements.

What is a gallon container?

Nursery containers come in a variety of different sizes, and old-school nursery slang has stuck. While the industry-standard terminology is to call the sizes "Gallon Containers", that doesn't exactly translate to the traditional liquid "gallon" size we think of. You'll find we carry young 1-gallons, up to more mature 7-gallons ranging anywhere from 6 inches to 6ft.

How does the delivery process work?

All of our orders ship via FedEx Ground! Once your order is placed online, our magic elves get right to work picking, staging, boxing and shipping your trees. Orders typically ship out within 2 business days. You will receive email notifications along the way on the progress of your order, as well as tracking information to track your plants all the way to their new home!

Why are some states excluded from shipping?

The short & sweet answer is: "United States Department of Agriculture Restrictions." Every state has their own unique USDA restrictions on which plants they allow to come into their state. While we wish we could serve everyone, it's for the safety of native species and helps prevent the spread of invasive disease & pests. We've gotta protect good ole' Mother Nature, after all.

About Me


The Coral Knock Out® Rose is the latest edition to this wonderful range of garden shrub roses, and it’s a real winner. The gorgeous blooms begin dark orange and then transform into shades or rich coral, while filling the air around them with delicious rose perfume. Blooming is continuous throughout the summer and followed in fall by a display of bright red rosehips. A vigorous shrub, this plant will reach its full size of 5 feet tall and wide within just a few years. The glossy dark-green foliage emerges bright bronzy-red, adding early color, and then it stays fresh green and abundant all season, because this plant is very disease resistant.

  • Continuous blooming all summer long
  • Gorgeous dark orange blooms become rich coral pink
  • Substantial garden shrub to 5 feet tall and wide
  • Especially recommended for hot zones, but also cold resistant
  • Very disease resistant, so always green and healthy

The Coral Knock Out® Rose should be planted in full sun, but it is also special for growing and blooming well in partial shade. The soil should be rich and moist, but well-drained, for the best growth and blooming. This bush is recommended for hot and humid zones, but it is also hardy through zone 5, without winter protection. Resistant to both black-spot and powdery mildew, the leaves stay beautiful all season, and its abundant flowering is protected by its resistance to the rose midge. Dead heading is not needed, but spring pruning and fertilizing is recommended.

Plant Hardiness Zones 5-10
Mature Width 4.5-5.5
Mature Height 4.5-5.5
Sun Needs Full Sun, Partial Sun
Zones 5-10

The Coral Knock Out® Rose is the most recent addition to the amazing Knock Out® series, which has been bringing a whole new look in roses to our gardens. Continuous blooms combined with disease resistance and easy-care makes these the roses of the future, but available today. Coral tones are much rarer in roses than reds or pinks, which the earlier Knock Out roses were, so it’s understandable that we have had to wait a while for that color to arrive, but here it is. Roses are known to grow best in cooler climate zones, and many finish blooming once the weather becomes hot, and they often sulk and develop diseases in humid conditions. If you live in those conditions you may already know this. But it is not true of all roses, and very untrue of the Coral Knock Out Rose. It’s wonderful coral pink coloring develops best in hot, humid climates, and its incredible disease resistance makes sure it stays healthy through the heat of summer, blooming continuously and making a spectacular show.

The Coral Knock Out Rose grows into a full and bushy shrub, reaching over 5 feet tall and wide within 3 years, and with an abundant leafy form, rounded, and casually bushy, completely different from those gaunt and leggy rose plants you might have grown in the past. This rose is truly a handsome garden shrub, full of grace and beauty. The new growth is a bright bronzy-red, adding color early in the year when it’s not yet in bloom, and the leaves matures to a rich, dark green. The leaves have a healthy and attractive gloss, and since this plant is very resistant to both black spot and powdery mildew, the foliage stays on the stems all season, staying healthy, glossy, and green.

Soon after the Coral Knock Out Rose leafs out, blooming begins, and continues throughout the summer and into fall. All over the bush flower stems, 8 to 12 inches long, rise above the foliage, and each one carries at least 5 fat flower buds. These open into classic high-centered roses, with about 15 petals in an open form. As the flowers develop, they become cup-shaped, measuring 3½ inches across. The blossoms have a wonderful rich fragrance of classic rose, brightened with citrus notes. Each bloom goes through amazing color changes as it develops, so that it can seem like no two roses on the bush are the exact same color. Young blooms are a rich dark-orange, then they transform into a wonderful coral pink. In hot humid weather they hold that color until the petals drop, and in cooler conditions they become lighter, approaching a blush coral to pinky-cream. When the blooms are finally done, they don’t hang on the plant looking sad and brown – no, the petals drop cleanly, leaving room for more blooms to develop. If you don’t dead head (and visually there is no need), the flower shoots develop into clusters of red rosehips, which brighten the bush in fall, adding more color to your garden.

Grow the Coral Knock Out Rose as a stand-out specimen in your shrub beds. Alone, or planted in groups of 3 or 5, spaced 4 feet apart, it will bring a fabulous and continuous display of wonderful color. Plant it near a path so you can enjoy the fragrance and beauty when passing or plant a row along a fence or driveway for a wonderful display. Plant it to fill spaces between your clipped evergreens, or in the corners of smaller beds for a striking background. This plant will change your view of roses forever, making a plant that was once fussy and unreliable into a wonderful easy-care garden shrub.

Plant the Coral Knock Out Rose in full sun or partial shade. Yes, this is a rose that is also remarkable for growing and blooming with some hours of the day spent in shade – something that few other roses can do. The soil should be rich, deep and well-drained for the best growth, and a steady supply of water will keep it blooming continuously. Trim out any weak, broken or dead twigs, and cut back the remaining branches by one-third, at a point just above an outward-facing bud. Older plants should have some of the oldest branches removed low down, to encourage new replacement branches. We have already mentioned how amazingly disease resistant this bush is, to both black spot and powdery mildew. It is also resistant to the nasty rose midge (Dasineura rhodophaga), a little-known but widespread insect that eats the growing tips of your bushes, drastically reducing flowering. Resistance to this pest makes sure you have lots and lots of blooms, free of serious problems. Feeding your bush in spring with a blended slow-release rose fertilizer is recommended for optimal growth and maximum blooming. 

The Coral Knock Out Rose was created by the rose breeder Will Radler, from Greenfield, Wisconsin. He won the All-America Rose Selections prize in 2000 for his first Knock Out rose, and since then he has continued to breed them, adding more varieties each year to the range. The variety he calls ‘Radral’ began its life around 2003, when he crossed two other varieties, ‘Radorg’ and ‘Rader’, which he had earlier developed as breeding material. Among the seedlings he found a vigorous and prolific bloomer with the orange and coral tones he wanted. In 2007 ‘Radral’ was released as “Carefree Celebration”, part of the Celebration rose series created by Star Roses of California. In 2009 Radler was granted a patent on his new rose, and in 2018 it was re-released as “Coral” in Star Roses’ Knock Out® rose collection. This wonderful rose is being highly praised for its great beauty and garden virtues. Our rose bushes always sell out fast, so order now, because this rose will not be available for long.

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Coral Knock Out® Rose

Rosa 'Radral' (PP#19,803)