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Knockout Roses

Knock your socks off with these timeless classics.

Double Knockout Roses

Rose Bushes and Trees have long been planted in gardens throughout the world, yet the Rose can be a high maintenance flower. That is why William Radler, a Rose breeder, cultivated the now famous Knockout Rose cultivar. Unlike their counterparts, Knockout Roses are cold-hardy, heat-hardy, and simply require less day-to-day maintenance from the gardener. Simply provide an adequate planting location, either in groups or individually, with proper watering, and be sure to prune the Knockout Rose once a year in early spring.

The colors will also astound. The Double Pink Knockout Rose and the Sunny Knockout Rose have rich, warm colorful blossoms. Knockout Roses typically also produce more blooms annually than their cousins. Plant the Knockout Rose in a sunny or partially shady location where its accented coloring will capture attention. These floriferous cultivars will bloom from spring to fall, painting the yard in lemon-yellow and vibrant pink for three full seasons.

It is vital that proper research is done prior to purchasing and planting any tree or shrub. Knockout Roses, though hardier than the Rose, are best grown in USDA Hardiness Zones 5 through 10. The hardy Knockout Rose also requires less daily sunlight, so it can be planted in a wider variety of locations throughout the property. Read the quick-facts below before exploring the following sections to determine if the Knockout Rose is well-suited to the planting location.

How to Buy Knockout Rose Bushes

The Knockout Rose cultivar is a valuable and much-loved plant. The young Knockout Roses require proper care and cultivation during the initial stages of growth, which in turn affects later development. The Tree Center provides this proper care, shaping the future growth of the Knockout Rose. Choose the specific cultivar and order from The Tree Center today.

How to Plant Knockout Rose Bushes

Sun: Plant in full sun to partial shade, providing between 5 and 6 hours of sunshine a day.

Water: Water immediately after planting and twice a week to a depth of at least 2 inches. Water in the morning from the ground up. Avoid wetting the foliage.

When to Plant: Plant in early spring, though the Knockout Rose can technically be planted at any time of the year.

The first step in the Knockout Rose planting process is to determine an appropriate location for planting the cultivar. Knockout Roses require adequate sunshine, although some partial shade can be managed by the rose. Although Knockout Rose bushes are hardier, they still benefit from between 5 and 6 hours of sunshine and adequate watering.

Knockout Roses can be planted in containers, in a flat garden bed, or in a raised garden bed. Raised garden beds are preferred, as the soil will drain water more quickly, to the benefit of the plant; however, the Knockout Rose can be planted in any of these locations and grow beautifully.

Once the planting location has been determined, order the chosen Knockout Rose cultivar from The Tree Center. When it arrives, examine the root ball, or the collection of roots at the base of the plant.

Dig a hole for the Knockout Rose that is twice as wide and twice as deep as the root ball. This is dissimilar from many other trees and shrubs, where the holes are typically not as deep. This is because Knockout Roses benefit from well-draining soil. Add a layer of compost or mulch to the bottom of the hole, turning it into the soil. This should fill the hole so that when the Knockout Rose is placed it the hole, the top of the root ball extends an inch above the soil level. The rose will settle over time. Backfill the hole with soil and water. Mulch and water immediately.

Soil Type

The soil surrounding the plant is important, as it is responsible for providing air, water, and nutrients to the plant’s root system. Soils can be characterized in a variety of ways: pH level, soil type, grain size, nutrient content, and drainage are the most commonly used categories.

Knockout Roses prefer well-draining loamy soil with a pH between 6.0 and 6.5. The drainage of the soil refers to the ability of the soil to drain water and liquids. One way to test for drainage is to dig a small hole in the soil just before it rains. Come back to the hole after the rain has passed. If the water is gone, the soil drains well. If the water is still in the hole, the soil drains poorly. Adding mulch or compost to the soil increases its ability to drain.

Alternatively, soil drainage is often associated with soil type. There are four types of soil with which gardeners typically work: clay, silt, sand, and loam. Clay and silt are composed of small particles. Water and air do not move through these soils easily. On the other hand, sand is made up of large soil grains. These grains drain soil too quickly. Loam is the best soil, as it is a combination of differently sized particles, thus moderating water drainage. The pH of the soil can be determined through a simple at-home soil test kit or by having a local landscaper test the soil.

Water Access

Knockout Roses, although significantly less prone to drying out and fungal diseases, still struggle with these issues. It is important to provide plenty of water to the Knockout Rose. The best way to water the Knockout Rose is with a drip or soaker irrigation system, which waters the rose regularly and from underneath. If overhead watering is necessary, be sure to water in the morning. If the Knockout Rose’s foliage is wet too late in the day, it will not have time to dry before evening, increasing the likelihood of developing a fungal disease.

Mulch and Fertilizer

Using mulch and fertilizer is one way to ensure better growth from the Knockout Rose, especially if the soil or location is compromised in any way. Mulch should be used when planting the Knockout Rose. Mulch assists with water conservation, water distribution, soil composition, and disease resistance. Simply place a three-inch layer of natural mulch, such as those composed of wood chips or bark, around the base of the Knockout Rose in a three foot radius. Be sure the mulch does not come into direct contact with the stem of the Knockout Rose.

Fertilizers are helpful when planting Knockout Roses. If choosing to use fertilizer, find one with a 1-2-1 ratio; although, 12-6-6 and 10-20-20 fertilizers have also achieved success. The ratio simply refers to the balance of nitrogen, phosphorus, and potassium, respectively. Fertilize the Knockout Rose once every 5 weeks.

Information on Knockout Roses

William Radler’s award-winning Knockout Rose cultivars are popularly planted for their hardiness, resistance to disease, and floriferous blooms. Developed and released in 2000, the Knockout Rose cultivar has become one of the most commonly planted roses. Gardeners appreciate the low-maintenance and resource conservation the Knockout Roses enable.

Knockout Rose Varieties and Cultivars

William Radler’s cultivars are limited. The Tree Center carries two of the most popular Knockout Rose varieties: The Double Pink Knockout Rose and the Sunny Knockout Rose. Bountiful flowers for three seasons abound on both cultivars.

Double Pink Knockout Rose

Hardy in USDA Hardiness Zones 5 through 10, the Double Pink Knockout Rose displays two layers of vibrant pink petals. These low maintenance, disease resistant roses grow well in many soils and locations, although they prefer sunny locations with adequate water access and well-draining soil. The Double Pink Knockout Rose reaches between 3 and 4 feet tall and 3 and 4 feet wide.

Sunny Knockout Rose

The Sunny Knockout Rose has warm yellow blooms, reminiscent of lemon or butter. Lighter outer edges of the large petals encircle inwards to darker yellow shades. These easy-to-grow roses have blooms for as long as 9 months of the year. Hardy in USDA Hardiness Zones 5 through 9, the Sunny Knockout Rose reaches between 3 and 4 feet tall and between 3 and 4 feet wide.

Benefits of Knockout Roses

Roses are a popular gardening plant simply because they are so beautiful and fragrant; however, gardeners have struggled with the basic variety for generations, as the regular rose can be quite needy. Knockout Roses provide all of the aesthetic beauty of the rose with the easy-maintenance every landscaper can appreciate.

Knockout Rose Concerns

Knockout Roses are resistant to many diseases and pests that affect regular roses. In addition, they can survive in a wider variety of locations with limits on sun and water access. Despite this, the Knockout Rose is still vulnerable.

Most notably, the Rose Rosette Disease, which causes bright red shoots to spout, dismantling the blooms slowly and eventually killing the rose plant. The disease, caused by a virus is spread by mites. Cutting the red shoots off immediately upon signs of Rose Rosette Disease can stop the spread; however, as soon as the disease has affected the entirety of the plant, the Knockout Rose will not survive.

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