how to plant knockout roses

How to Plant Knockout Roses | Tips For Growing Them

Knockout roses are one of the versatile, beautiful, and pleasant flowers. These roses can grow in various adjustable environments. And the great thing is, they come with different color options.

Compared to roses, knockout roses are less prone to diseases, heat-tolerant. Most gardeners love to grow knockout roses because of this feature.

However, being a low maintenance plant, knockout roses need minimal care.

This guide will cover all the questions on how to plant properly knock out roses.

Keep on reading.

Step By Step Process to Plant Knockout Roses:

Knockout Roses can be planted in containers. In that case, the container has to be fairly big. But the best way to plant knockout roses is to plant them in the ground. Follow the below guidelines:

● Without proper sunlight, knockout roses can’t bloom. The first thing you will need to do is to select a place where sunlight stays at least 6 – 8 hours a day.

● Choose well-balanced soil to plant a knockout rose. The pH level has to be a minimum of 6. If your garden or lawn soil’s pH level is not yet tested, no worries because the pH level of the soil is 7 (neutral) – which means soil pH level is not acidic nor alkaline. The soil needs to be slightly acidic; you can add a coffee ground to the soil to increase the acidic level a little bit.

● The selected place has to have a good drainage system. It is because the wet root is not good for knockout rose’s growth.

● Spring or fall is the best time to plant knockout roses.

● Ensure keeping 3 ft distance between every bush, center to center.

● Now it is time to dig a hole. What should be the measurement? The hole should be 2X wider than your plant and similar depth to the plant pot. Make sure to loosen some soil of the hole bottom and roots underneath the plant. Place the plant into the hole and use good soil to fill the hole up. The ground level and the top part of the plant-soil should be well-leveled.

● Proper mulching is the secret of a healthy plant. Rotting may happen if you don’t mulch about 6” away from the bush base. Ensure maintaining the measurement.

● Water your newly planted knockout rose.

● Often we transplant knockout roses bush. It would be best to do it in the early spring since in the late spring, Knockout roses bush starts growing.


● Regular watering is essential when you plant knockout roses in a container.

● In winter, ensure keeping the knockout rose container indoor. And water them now and then to avoid any drying out.

Fertilizing Knockout Roses

Knockout Roses can be grown without fertilizer just fine. Still, there are many good fertilizers out there if you want to boost up their growth. Follow the instructions below:

● Let the knockout rose to establish and then start fertilizing.

● Always look for specially formulated and the best fertilizer for knockout roses.

● Fertilizing is necessary once in a month from spring to mid-summer. After mid-summer, don’t fertilize the plant. From the summer-end, the plant is preparing itself for the winter. So it would be best if you didn’t fertilize more to let it grow more.

● Don’t fertilize when the soil is dry. Fertilizing works significantly in moist soil.

● It is advisable not to fertilize more. More fertilizing will aid the leaf growth, but you will not receive spectacular flowers.

Pruning Tips of Knockout Roses

Early spring is the best time to prune the bush. Ensure 12” – 18” pruning every year.

When you prune the plant in late summer or early fall, the plan will not get much time to harden. Also, growth will be late.

Watering the Knockout Roses

Watering once a week is great when the plant is established. Ensure adequate watering to the plant and let the soil dry appropriately before the next watering session. And if any rainfall is there, skip watering once a week too. As stated earlier, more watering will damage the root of the knockout rose.

Don’t water over the leaves; focus on the plant base and water there. The dripping hose is the best option because it will help you water the plant base instead of the leaves. Using a sprinkler is entirely a waste because water evaporation will happen during a hot or humid day, which will lead you to more water bills.

Also, morning is the best time to water knockout rose plants.

Protecting the Knockout Rose Plant

Mulching 2” – 3” deep is mandatory around the plant stem in harsh winter. And remember to remove the mulch in springtime.

Troubleshooting of the Knockout Rose and Solution

Your knockout rose plant will show some problems even after taking the utmost care of the plant. The essential thing is to react to the situation quickly.

Yellowish or brownish leaves

It happens when you water or fertilize the plant more. Give the plant much time to dry between 2 watering sessions. Also, yellowish leaves happen when the weather is too humid and hot. You have nothing to do since changing the weather condition is out of your control. Once the weather gets improved, the plant recovers itself.

Less Blooming

At the beginning of this article, I stated that sunlight is an essential thing for knockout roses. Less blooming happens when your plant doesn’t get much sunlight. That is why it is necessary to plant knockout roses where it can get direct sunlight for 6 – 8 hours a day.

Powdery Mildew

This is a fungal disease. Although knockout roses are less prone to diseases, that doesn’t mean they are disease-proof. You will find powdery mildew on the plant leaves in high or mild temperature days. Applying horticultural oil will help you to get rid of the problem.

You will never experience a powdery mildew problem in summer. So, you have to apply horticultural oil until the summer comes. Also, the trimming of the affected area is another option to solve the problem.


Question: What is the best fertilizer for knockout roses?

Answer: Organic fertilizers are best for knockout roses. The responsibility of organic fertilizers is to improve the growth of the knockout rose plant. However, depending on the knockout rose plant problem, you will need to choose the fertilizer. If the blooming rose is dying after a particular growth, apply bloom boosting fertilizer.

Question: How often do I need to fertilize the knockout rose plant?

Answer: Depending on many matters, you will get the answer to the question. In the growing season, you can’t avoid fertilizing at least once in a month. Based on the soil type, you will need to determine how much fertilizer is required for your plant. Clay soil requires less fertilizing, while sandy soil needs more fertilizer.


The gorgeous and elegant look of knockout rose is an eye-pleasing addition to every garden. Easy caretaking and maintenance of knockout roses make it a popular plant among many gardeners.

Do you have knockout roses in your garden? What color is your favorite?