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Red Knock Out® Rose

Rosa 'Radrazz' (PP#11,836)

2 Reviews

Red Knock Out® Rose

Rosa 'Radrazz' (PP#11,836)

2 Reviews


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


This amazing plant is covered with vibrant cherry-red flowers from spring, through summer and into fall – three seasons of gorgeous blooms. It forms a small bush, 3 to 4 feet tall and the same across. Unlike other roses it is resistant to black-spot and most other rose diseases. It will grow across almost all the country, from zone 5 to zone 9. It is happy in all kinds of soil and needs just the most basic care. If you love roses, but think they are too difficult, try the Knockout Rose and see how wrong you were. This rose has changed the meaning of ‘rose-growing’ into something simple that everyone can succeed at.

  • Cherry-red flowers smother a dense, rounded bush
  • Easiest type of rose to grow
  • Flowers continuously from spring to fall
  • Disease and pest resistant
  • Perfect choice for any garden

Plant your Knockout Rose in beds, among other shrubs, or among flowers. Use it to form a beautiful low boundary, or anywhere at all where you want continuous color and low-maintenance plants. Plant in a sunny location for the best flowering, but this tough rose will also grow in partly-shaded locations far better than other roses do. It will grow well in all kinds of soils, including heavy clays, and it is both cold and heat resistant. You will not believe how easy it is to grow your own roses, until you try the Knockout Rose.

Plant Hardiness Zones 5-9
Mature Width 3-4
Mature Height 3-4
Soil Conditions Well-Drained Soil
Sunlight Full Sun to Partial Shade
Drought Tolerance Moderate Drought Tolerance
Zones 5-9

The Knockout Rose is covered in brilliant cherry-red flowers from spring to fall, and this amazing bush is in continuous bloom for three seasons. This plant is as easy to grow as a plant can be. It requires only the most basic care, it is hardy across a range of climates and soils, and it will reward you with an endless succession of stunning red blooms that will light up your garden. Many roses only give bloom for a few weeks of the year and then they are just leaves, but the Knockout Rose blooms continuously. This shrub rose is the ideal height – big enough to make an impact but small enough to fit anywhere. Use one as an accent in your flower beds, slip some into your shrub beds, or plant a whole row along the drive, or at the foot of a wall. There is a place for the Knockout Rose in every garden.

Most roses are subject to a long list of problems. They start off well in the spring, but rapidly the leaves begin to turn black and fall off (black spot), or become covered in white powder (mildew) or black blisters (rust). This is not the case with the Knockout Rose – it is completely resistant to all of those diseases, as a result of years of careful breeding. Like other roses it may attract a few insect pests, but it is so hardy and vigorous that you will not even notice them. They will be ignored by your Knockout Rose as it blooms away all summer.

The Knockout Rose took the gardening world by storm when it was introduced by rose breeder Will Radler. He had worked for years to make a special rose that was disease-resistant. It won the coveted All-America Rose Selections prize in 2000. This prize is not just awarded on looks, but on the results of growing the rose in gardens all across the country – so it has to be good. Literally millions of plants of this rose have been sold across America every year – more than any other rose – and millions of gardeners can’t be wrong.

Growing Red Knockout Roses

The Knockout Rose forms a bush 3 to 4 feet tall and the same distance across. It has healthy, glossy leaves and the cherry-red flowers are so numerous they almost hide the foliage all spring, summer and fall. The flowers are produced continuously and unlike other roses, when they die they just fall off, leaving the plant constantly fresh and clean. This rose bush is hardy in zones 5 to 9, so it will grow throughout the country, from cold areas to warm ones. Everyone can grow this fabulous rose in their garden.

Planting and Initial Care

Your Knockout Rose will do best is a sunny location, but this is also one of the rare roses that will grow well in partial shade. If you have an area of your garden where you want a rose, but it is a little shady, then this is the rose to choose. Once established, it will easily handle regular summer conditions, but not drought, which will stop the flowering. It will grow well in all kinds of soils, including heavy clays. For planting in a row, place the plants 2 to 3 feet apart.

Because the Knockout Rose grows so strongly all the time, it will benefit from plenty of organic material (like compost or rotted manure) dug into the ground where you are planting it. You should also feed that vigorous growth with rose food, which should be added when planting, and again each spring and in mid-summer. Each spring, before the new growth starts, trim your bushes. Remove any thin branches at the best and cut the others back so they are 6 to 12 inches long. Your Knockout Rose will rapidly send out strong shoots and be back in bloom in just a few weeks.

Buying Red Knockout Roses at The Tree Center

The Knockout Rose is such a special plant that it is protected by patent. This means it must be produced under license directly from plants absolutely known to be right. Our plants are grown the correct way, from grafts of these special plants. That way every one is identical to the original. However, these take longer to produce, so avoid other cheaper roses that will only be a disappointment. We sell only plants that are true to the original form and we have a wide range of sizes to give you the best variety for your purpose. We are constantly renewing our stock so our customers get fresh, healthy plants, so our supplies of Red Knockout Roses may be limited.

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Red Knock Out® Rose

Rosa 'Radrazz' (PP#11,836)

2 Reviews