Shrub roses are easy to grow in the ground or in containers. Below are general guidelines for planting them in various types of soil, ranging from clay to sandy and loam soils, and in containers, planters and pots. 

Here's a breakdown of what you need to know...

(Scroll down to see planting instructions for containers and pots)


Soil
Shrub roses are very easy to grow in a range of soil types, but grow best in a moist but well-drained fertile soil. Constantly soggy or wet soil can be problematic. So make sure to plant in a well-drained site. 


How To Test Soil Drainage  If you are uncertain about soil drainage in the area you intend to plant your roses, it's well worth taking the time to test the drainage before planting. To test soil drainage, dig a hole 12" wide by 12" deep in the planting area. Fill the hole with water and let it drain. Then, after it drains, fill it with water again, but this time clock how long it takes to drain. In well-drained soil the water level will go down at a rate of about 1 inch an hour. A faster rate, such as in loose, sandy soil, may signal potentially dry site conditions. A slower rate indicates poor draining soil and is a caution you need to improve drainage, plant in a raised mound or bed, or look for plants that are more tolerant of wet or boggy conditions.

Soil pH
Shrub roses grow best in a moderately acid to neutral soil ranging from 6.0 to 7.0 on the pH scale. Most average garden soils fall between a pH range of 6.0 to 7.0. 


Testing Soil pH  Soil pH is a measurement of the alkalinity or acidity of soil and is measured on a scale of 1-14, with 7 as the neutral mark. Any measurement below 7 indicates acid soil conditions, and anything above 7 indicates alkaline. If you're unsure about the pH of your soil, or whether or not it's suitable for growing shrub roses, it's a good idea to test the soil pH in the planting area. You can quickly test soil pH with an inexpensive soil pH tester probe. To raise the pH (make more alkaline) you can add pelletized limestone to the soil. To lower the pH (make more acid) you can apply Soil SulfurAluminum Sulfate, or Chelated Iron. Adding organic compost to the soil or using compost as mulch can also help to increase acidity and maintain acid soil conditions.




Light Needs
Shrub roses grow best in full sun or part shade. Morning sun is necessary to dry the morning dew from their leaves. Filtered afternoon sun or dappled shade is fine. The densest growth and best flowering occurs with at least 5 hours of direct sun from spring through early fall, when plants are actively growing. 



Planting Instructions for Shrub Roses

(Scroll down to see planting instructions for containers and pots)

TIP: Water the root ball deeply before removing the plant from its container.

Step 1
Start by digging your planting hole at least two to three times as wide and as deep or not much deeper than the root ball of your plant. The wider the hole the better. Place native soil removed from planting hole around the perimeter of the hole, in a wheel barrow, or on a tarp.

Step 2
Depending on the type, fertility and porosity of the soil in the planting area you might need to amend the native soil. When planting in dense clay or poor soils it is beneficial to thoroughly mix in some composted organic matter, bagged top soil, sand, and/or a good planting mix at a 50/50 ratio with the soil removed from the planting hole. When planting in very sandy, quick-draining soil you might want to consider mixing in some top soil, peat moss and/or compost to help retain moisture. When planting in fertile, loamy, well-drained moist soil there is no need for adding a soil amendment.

Step 3
To remove your rose from the container it was growing in, firmly grasp the base of the plant and gently lift and remove it from its container. Since most shrub roses have some thorns, I'd recommend wearing thick gloves or wrapping the base of the plant with a thick towel or other material when planting. If the root ball is stuck in the container either cut the container away or place the plant on it's side and gently pound on the side of the container to loosen the root ball. After having removed the plant from the container, carefully loosen some feeder roots around the surface of the root ball. 

Step 4
Set your rose in the planting hole so that the top edge of the rootball is at or slightly above ground level to allow for settling. If the soil is somewhat slow to drain, plant with the root ball 2 or more inches above ground level. It may be necessary to place some of your backfill soil mixture in the bottom of the hole to achieve proper planting height.

NOTE: If the soil is poorly drained (constantly soggy or wet)  plant the root ball in a raised mound entirely above ground level or select a different plant species more tolerant of wet soils.  



Planting Diagram Knock Out Roses



Step 5
After setting your rose in the planting hole, use one hand to hold the plant straight while using your other hand to begin backfilling the soil mixture around the root ball, tamping as you go to remove air pockets. If the soil is dry, when you have filled the hole to the halfway point you can soak the soil. Then continue backfilling to the top edge of the root ball. If you are planting with the root ball above ground level, taper your soil mixture gradually to the ground level, essentially creating a raised mound. To avoid suffocating your rose, do not put any soil on top of the root ball.

Step 6 (Optional)
When planting a shrub rose in a location that is far from a water source, and in well-drained soil, you can use remaining soil mixture to build a water retaining berm (catch basin) around the outside perimeter of the planting hole. This basin will help to collect water from rainfall and irrigation often reducing the need for hand-watering. The berm can be removed after a year when the plant has established itself.

Step 7 
Next, deeply water the planting area, including the root ball, to a depth equal to the height of the root ball. For an extra boost, to stimulate early root formation and stronger root development you can also water you newly planted shrub with a solution of Root Stimulator, which reduces transplant shock and promotes greener, more vigorous plants.

Step 8
Apply a 1 to 2" layer of aged, shredded wood mulch or bark, or a 3- 4" layer of pine straw, around your newly planted rose. Do not use freshly chipped or shredded wood for mulch until it has cured in a pile for at least 6 months, a year is better. Avoid placing or piling mulch directly against the base of the rose as this could cause the bark to rot. There are several benefits to mulching around your newly planted rose. Mulch applied correctly will help retain the moisture and prevent weeds that would compete with your rose for water. 


How To Plant a Shrub Rose in a Container


Shrub roses growing in pots appreciate a moist but well-drained soil. Constantly soggy soil will often cause root rot or other harmful or deadly plant diseases. Therefore, when planting in a container or pot, I recommend using a high quality potting soil or professional potting mix, or a 50/50 combination thereof. You can also add some pumice (maybe 20%) to the soil mixture to help with drainage, especially with shrubs that really need a well-drained soil. Pumis is an excellent soil conditioner, as it is highly porous providing excellent water, air, and nutrient holding capabilities. Pumice will not decompose or compact over time and is very lightweight. Agricultural grade pumice can usually be found at local feed stores as a product called Dry Stall. The particle size is about 1/8". It's a good idea to wash the product before use to remove the fine particles. If you can't find Pumice you can substitute with perlite.

Also make sure to choose a container with drainage holes at the bottom and one that is large enough to allow for 2 to 3 years of growth before shifting up to a larger size container. This might mean your planting pot would be 5-6 inches or more in width than the root ball of your plant. 

Container color will matter as well. Not only will you want to pick a color of container that goes well with the flower and foliage color of your Knock Out Rose, you'll also want to pick a container that matches the style of your home or other structures and other plants in the surrounding environment. 

Many nursery & garden centers offer a wide variety of containers to choose from. Before heading out to buy a container take pictures of your home and the surrounding environment. Doing so will help you to choose just the right color and style.


Container Planting Instructions

Step 1
Before filling your container with soil, we recommend lining the bottom with shade cloth or a porous landscape fabric. This will keep the drain holes from becoming stopped up with soil. 

Step 2
To remove your rose from the container it was growing in, firmly grasp the base of the plant and try to gently lift and remove it from its container. Since Knock Out Roses have thorns, we'd recommend wearing thick gloves or wrapping the base of the plant with a thick towel or other material before handling the plant. If the root ball is stuck in the container either cut the container away or place the plant on it's side and gently pound on the side of the container to loosen the root ball. After having removed the plant from the container, carefully loosen some feeder roots around the surface of the root ball. 

Step 3
Pour a small amount of your soil mixture in the bottom of the container. Set your rose in the container and make necessary adjustments by adding or removing some soil so that the top edge of the root ball will sit 1/2 to 1" below the rim of the container.



Step 4
Backfill with your potting soil around root ball, tamping as you go, until the level of potting soil is even with the top edge of root ball.

Step 5
Water thoroughly until water starts to drain from the holes in the bottom of the container. Add more potting mix if settling occurs during watering.

Step 6 (Optional)
Apply a 1/2" layer of wood chips or sphagnum moss to soil surface to help conserve moisture. You can also incorporate low growing, spreading plants in your container planting that will serve as a permanent soil cover.



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