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Rosa ‘Radtko’ PP16,202 KO

Status: In stock

Product ID#: rdkno
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Starting at: $60.99
Product Description
Sun Exposure Sun
Bloom Time Summer, Fall
Soil Conditions Normal, Sandy, Clay/Heavy, Dry
Flower Color Red
Fruit Color Orange, Red
Mature Plant Size (H x W) 3-4' x 3-4'
Double Knock Out® continuously produces double vibrant red flowers with a slight, spicy apple fragrance. It is resistant to blackspot and downy mildew. It has all of the same excellent qualities of Knock Out® but with double the number of petals, making it a nice full bloom rose. This plant works great as a low hedge or accent. Mulching late in fall will help ensure that the crown survives the winter.

Bring Red Blooms to Your Garden with McKay Nursery

Here at McKay Nursery, we give access to a selection of curated plants, including the eye-catching Double Knock Out® rose shrub. Located in Waterloo, Wisconsin, our nursery grows hardy and vibrant additions for your landscape design. Order your Double Knock Out® rose today and receive top-quality plants grown by our experienced nursery team.

For more information, contact us at [email protected] or call us at 920-478-2121.
  • sunshade Sun
  • Mature Plant Size (H x W) Mature Plant Size (H x W): 3-4' x 3-4'
  • Bloom Season Bloom Season: Summer, Fall
Key features
  • Attracts Bees
  • Drought Tolerant
  • Salt Tolerant
  • Low Maintenance
  • Long Blooming
  • Attracts Butterflies
  • Cut Flower
  • Fragrant Flowers
  • Attracts Pollinators
Planting Care

Planting & Care for Double Knock Out® Rose (Rosa ‘Radtko’ PP16,202 KO)

Preparation
  • Roses may be mass-planted in beds and borders or planted alone in the garden.
  • The hardiness of roses vary.
  • Double Knock Out® roses have a similar bloom cycle to Knock Out® Roses.
  • Many roses may tolerate extreme cold, while others can be singled by frost.
  • To form stocky shoots and flower bountifully, roses need full sun all day.
  • Good air circulation is important, but shelter from strong wind to avoid flower damage.
  • Rose shrubs prefer heavy but well-drained, humus-rich loamy soils.
  • You can improve light, sandy, gravelly, or chalky soils by adding large amounts of well-rotted manure or decomposed garden compost several weeks before planting.
  • Add garden lime to highly acidic soils.
  • Mulching late in the fall will help ensure that the crown survives the winter.
Opening Plant Material
  • Bare Root: Cut open the bundle (top and roots are tied) and separate all the plants. Soak roots in buckets of water until planted. Each plant type will be labeled separately for identification. Keep the roots from full sun since they should never dry out. Keep roots covered. All bare-root plants must be trimmed when planted.
  • Containers: Completely saturate all container plants by putting them in a larger water container until bubbling stops. Remove the plant, then dig a hole no deeper than the depth of the container, ensuring it’s wider on the sides by an additional 6” or more.
Planting Bare Root
  • Plant bare root in spring or fall. A good indicator of whether you can still plant is if the ground is still workable. If a hard frost is expected, hold off on planting.
  • Dig a hole at least 6" wider and the same depth as the root mass. The crown or graft of the plant should be slightly higher than ground level where it was grown at the nursery.
  • Trim off the broken roots and branches.
  • Place fertilizer packets in the hole (if purchased). Do not place other fertilizers in the planting hole. *Use Our Recommended Fertilizer.
  • Spread the roots and fill halfway with soil, then water until the soil settles completely, saturating the soil and planting pit.
  • Re-adjust the plant and fill the hole with the rest of the soil.
  • Backfill the balance of the soil and water well.
Planting Containers
  • Shrub roses can be planted March to November.
  • Dig a hole no deeper than the depth of the container and 6" or wider on the sides.
  • Slide the plant from the pot by tapping on the bottom of the pot.
  • With a shovel or knife, trim the bottom 2" off the root ball for plants in plastic containers.
  • Rotate the plant to the proper position. Never lift or move plants by the tops.
  • Place the root ball in the hole.
  • Adjust the plant height so the root crown is slightly higher than the ground.
  • Notice where the base of the trunk flares out from the tree. This is called the root flare. This root flare should show when the tree is planted. Add soil under the ball so the root flare is exposed if necessary.
  • Place fertilizer packets into the bottom of the hole (if purchased). *Use Our Recommended Fertilizer.
  • Backfill the hole with soil, ensuring the top of the root ball is visible and slightly higher than the soil around it.
  • Firm the soil around the plant. Water well to settle soil around the root ball.
  • Check out our Planting & Handling Guide for additional planting information and illustrations.
Pruning - After Planting
  • Bare Root: Prune ALL bare root plants to reduce transplant shock and ensure successful planting. Pruning should occur as soon as possible, before or after planting, and with sharp pruning shears.
  • Containers: Although it’s not essential after planting, light pruning can help shape a Double Knock Out® Rose shrub. Doing so removes any broken branches from shipping or thins out a heavily branched plant to assist in the transplanting process and the appearance of your new planting.
Pruning - Through-out the Season
  • Tackle pruning in early spring before buds burst. Typically this is done from March to April.
  • In fall, shorten extra-long stems on bush roses to avoid them catching the wind and loosening the stem.
  • Always cut to just above a bud.
  • Top back some branches to improve the general shape.
  • Cut the shrub back to at least ½ its original size to promote new growth from the base.
  • Deadhead all roses weekly to channel energy into new shoots and more flowers.
Watering - After Planting
  • Plants typically take approximately 6 weeks to establish new roots in your soil. During this period, water plants as often as every 2-4 days at the start and at least a minimum of once per week.
  • Beyond the six-week establishment period, water once per week unless rain occurs.
  • Remember to check soil moisture by sticking your finger into the soil around 3”.
Watering - Through-out the Season
  • After the first season, plants should only be watered during extended periods without rain.
  • How do you know if your plants need water? The easiest way to tell is to touch the soil around the roots. If it is moist, there is no need to water. If it’s dry, give it a good soak with the hose end (no nozzle), watering the soil only, not the leaves.
  • Same as after planting, stick your finger into the soil around 3” to check soil moisture.

Frequently Asked Questions

How long do Knock Out® roses live?

With proper planting, care, and annual pruning, Knock Out® roses can stay alive for decades.

What is the best growing zone for Double Knock Out® Roses?

When planted in the recommended hardiness zones 5 to 9, Knock Out® roses can flourish in various temperature and humidity levels. In colder areas, these roses can be grown in containers and relocated to a protected spot during severe cold weather.

Do Double Knock Out® Roses need overwintering?

Knock Out® Roses are heat tolerant, but they will require some winter protection even if they’re more winter hardy, unlike other roses. If you reside in a region with severe winters, apply 2 to 3 inches of mulch around the base of your rose plants or wrap them in burlap. A snow cover can also help insulate and protect the rose plant throughout the winter. In the spring, remove the burlap and prune any dead or broken canes. Also, clear away any excess mulch.

Why are the leaves on my Double Knock® Roses turning yellow?

If the foliage on your rose bush is turning yellow, it may be due to overwatering or high temperatures. Remember to only water at the bottom of the plant. Check the soil moisture to ensure the plant does not have wet roots. If your plant is experiencing intense heat, it may be advisable to move them indoors if they’re in containers.

What are the common issues with Double Knock Out® Roses?

Knock Out® roses are generally low-maintenance and disease-resistant, but they can still be susceptible to black spots and fungal disease.

Black spots can appear on the rose bush’s leaves when planted in humid areas. This issue can typically be resolved by watering only at the base of the plant.

Powdery mildew is a fungal disease that appears during cool, humid days. It can be treated by applying horticultural oil or trimming back the affected areas.

Besides these diseases, Knock Out® roses also require pruning to maintain their shape.

Planting & Handling Help

Download our Planting and Handling Guide below to plan for a successful arrival and install of your plants. Be sure to water all plants as soon as they arrive and every day until you’re ready to plant. Keep any bare root bundles in a shady, cool spot with the roots covered at all times.

Learn More

Watch our videos on handling bare root plants, how your order is prepared for shipment and more.

Plant Sizing

What is the difference between Containers, Grow Bags, Bare Root, and Balled & Burlap (B&B)?

Shipping Times

Our FedEx and local shipping times depend on two factors, one is by the region and the second is the type of product being shipped. For example, small fruits are only shipped in spring, but majority of our perennials are shipped from spring until fall. Keep in mind the dates below act as a general guide. Due to unpredictable weather, staffing, inventory and industry demands these timelines can change. Therefore, we cannot guarantee any of these times.

 

Shipping Dates by Region*

 

Northern Cold Region: April 22nd - November 7th

Northern Region: April 15th - November 7th

Middle Region: April 1st - November 7th

Southern Region: March 15th - November 7th

Local Delivery (small radius from Waterloo, WI): April 22nd - November 7th

 

Shipping Dates by Season*

 

Spring Shipping: Region Start Date (above) - May

Fall Shipping: September - November

 

Due to unpredictable weather, these times may vary. Some varieties are exceptions due to heat and plant health reasons. Enter your shipping zip code at the top of this page and be sure to check the shipping information on each product before you add it to your cart. If the product is too large or restricted in your state, you will not be able to checkout with that item in your cart.