How to prune Knock Out Rose shrubs? That’s the question we receive today and one that is worth addressing. Although Knock Out® roses are hybrid shrub roses, resistant to disease, they are still ROSES. They should be treated as such.

Leave the Knock Out rose to grow during its first year, waiting until its second year in the ground to do the first pruning.

The best time to prune is while the plant is dormant, just before bud break. Which should be happening very soon.

Naturally that depends on the climate in your area. But, for most of the country, your window to prune is getting quite short — it should be done by the end of March.

What you need to prune your Knock Out roses:

• Puncture-proof gloves
• Sharp pruning shears (have you tried Felco 2? They’re amazing and last forever).
• Tub or bucket
• Lysol disinfectant
• Rake
• Fertilizer
• Mulch

Here’s your pre-pruning routine

Pour the Lysol into a tub, full strength, and add your pruning shears. Let them soak for 5 minutes.

Grab the bucket, with the shears still inside, and head outside to your Knock Out rose. You’ll need the solution to dip the pruners when you switch from one bush to another.

Clear the soil beneath the Knock Out rose of any leaves, flowers and old mulch. Bag it up and dispose of it.

Let’s get pruning!

Cut off all dead roses and any black twigs or canes.

Remove branches that stick out from the rest of the plant. Cut these branches, at a 45-degree angle, just above a bud that is facing the direction you want the branches to grow. That’s the most important part of pruning roses — you can control their form, just by pruning properly.

Stand back and check the shape of the Knock Out rose shrub. It should have an evenly rounded appearance and stand 25 to 30 inches tall.

The finale: Fertilizer

Fertilize the Knock Out rose immediately after pruning. In fact, the ideal times to fertilize each year are April, June and August.

The folks at KnockOutRoses.com suggest using a balanced fertilizer. The most commonly available formula is a 10-10-10. This is fine for the April and June applications (although we use BioAdvanced Rose and Flower fertilizer, 6-9-6). b

If you hope for a fall flush of roses, however, use a 2-4-1 fertilizer (or close to it. We like Neptune’s Harvest) and apply in late August or early September. Then switch back to the other formula for the spring and early summer fertilizer applications.

Use the rate recommended on the fertilizer label and always apply fertilizer to wet soil.

Add some fresh mulch to the soil, 2 inches away from the base of the Knock Out rose shrub.

And, there you have it. Roses are such easy growers. Really, it’s hard to kill one.

Need good pruners? We review the top three here.

Shop for Knock Out roses at Nature Hills Nursery, online.

Learn How to Grow Roses in Containers