Triple Knock Out® Rose

Light Needs

Full Sun

6+ Hours

Mature Height

3 Feet

Mature Spread

2-3 Feet

Growing Zones

4 to 11

Triple Knock Out® Rose

Extra-full blooms with a traditional garden rose form and noticeable fragrance.

Flower Fullness 30–35 Petals Very full, layered bloom

• Size 3' H × 2–3' W
• Hardiness Zones 4b–11
• Fragrance Sweet Floral (Strongest)
• Rose Style Grandiflora

Double Knock Out® Rose

Full double flowers with a classic rose appearance.

Flower Fullness 18–24 Petals Full, double bloom

• Size 3–4' H × 3–4' W
• Hardiness Zones 5–11
• Fragrance Fruity, Sweet
• Rose Style Landscape Shrub Rose

Knock Out® Rose

The original with simple, open flowers.

Flower Fullness 7–11 Petals Open, classic bloom

• Size 3–4' H × 3–4' W
• Hardiness Zones 5–11
• Fragrance Subtle Sweet
• Rose Style Landscape Shrub Rose

Triple Knock Out® Rose packs 30-35 petals into each deep red to rich pink bloom, for a fuller, classic flower form. Rosa ‘Radtriple’ grows into a compact, bushy shrub about 3 feet tall and 2–3 feet wide, with the easy-care performance that made Knock Out® Roses famous. The flowers appear repeatedly from spring through frost and carry a sweet floral fragrance, adding another dimension to a rose already loaded with color.

Bred by Will Radler, Triple Knock Out® is the first Grandiflora introduced into the Knock Out® Family and has roughly triple the petals of the original Knock Out® Rose. The extra petals create a layered, traditional rose shape. It was selected after extensive trialing for disease resistance, hardiness, growth, and repeat flowering. The medium-green foliage looks clean throughout the growing season, and reblooming continues with minimal upkeep.

Its compact habit makes Triple Knock Out® easy to use throughout the landscape. Plant several together for a flowering hedge or mass planting, feature one near an entry or patio where you can enjoy the fragrance, or mix it with perennials and other flowering shrubs. It also works well in larger containers when you want the appearance and fragrance of a traditional rose without committing to a high-maintenance rose garden.

Triple Knock Out® Rose Care

Grow Triple Knock Out® Rose in full sun for the strongest flowering and healthiest growth. Plant it in fertile, well-drained loamy soil enriched with organic matter, although amended sandy or clay soils can also be suitable when drainage is good. A slightly acidic soil pH around 6.0 to 6.5 is preferred. Plant with the top of the root ball level with the surrounding ground. 

Water deeply and regularly during the first growing season to help the roots establish, checking the soil often for dryness. Once established, Triple Knock Out® handles short dry periods well, though deep watering during prolonged heat and drought helps sustain flowering. Apply a rose or balanced slow-release fertilizer as new growth begins in spring, following label rates and watering it into the root zone. 

Triple Knock Out® does not require routine deadheading to continue blooming, making it considerably easier to maintain than many traditional garden roses. Prune in late winter or early spring before new growth takes off, removing damaged or crossing branches and cutting the plant back as needed to maintain its compact shape. A layer of mulch around the root zone helps conserve moisture, suppress weeds, and protect roots through temperature swings.

Triple Knock Out® Rose Spacing

Space plants about 3 feet apart for individual shrubs with defined outlines, or somewhat closer when developing a continuous flowering hedge. For containers, use a pot at least 18 to 20 inches wide with generous drainage holes and a high-quality outdoor potting mix. Container-grown plants dry more quickly than those in the ground, so check moisture frequently during hot weather and provide winter protection in colder zones. 

Triple Knock Out® Rose Companion Plants

Ornamental allium can surround Triple Knock Out® Rose with rounded spring flower heads before the rose reaches its strongest summer bloom; both perform well in sunny, freely drained beds. Catmint makes another compatible landscape partner, contributing fine-textured foliage and contrasting blue-purple flowers along the front of a well-drained rose planting. For large mixed containers, calibrachoa can trail over the rim beneath the compact rose canopy, extending color toward the edge of the pot while sharing its preference for abundant sunlight.

Triple Knock Out® Rose Information

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