Knock Out Roses With Red Purple Canes and Leaves

red purple canes and leaves on knockout rose

Patty is concerned about the color of her knock out rose canes and leaves.

She writes: I have beautiful Knockout Roses. They are two years old. They are planted twenty feet apart.

I lost one last year and in the same spot this year I lost the second. Now this summer the other group is showing the same signs.

Dense formation of prickles on the canes and stems. Canes and leaves are deep red and purple in color.

Is there any way to save the rest? The tea roses in the same bed are not affected. Thanks so much!

My reply:

Hi Patty
the dense formation of prickles along the canes and stems is nothing to worry about, as that is typical of a knocout rose bush.

Also the description of the canes and leaves being a deep red and purple color sounds like it is just putting on new growth.

As you can see from the picture at the top left of this article, the purpley-red new growth (where I have white arrows pointing) is typical of the color of the new growth of knockout roses. Actually it is a good sign that the plant is growing.

I don’t know what could have caused the death of your other knock out rose last year, but I would inspect your knockouts on a regular basis to be on the lookout for any sign of pest or disease problems that may have contibuted to that other rose’s death.

Knockout roses are hardy roses and aren’t troubled by the usual rose disease problems, but to be on the safe side and control any future problems with your other knockouts, just be vigilant with checking them over when you’re watering them. That way you can be on top of any problems before they get a hold of your rose plants.



Help! Have I Killed My Potted Knockot Roses?

potted knockout rose

Thomas has written in concerned that he may have killed his potted knockout roses. Here’s his story:

I purchased knockout roses about two weeks ago. I haven’t planted them yet, they are sitting on my patio (1st week shade/ 2nd week full sun). I’m not sure what happened but they looked very healthy when I purchased them. They were starting to bud during first week but over the weekend I noticed that the buds are dying and the leaves are also withered and dying.

I was watering them once a week and it also rained a few days last week. I have since removed the dead leaves, etc. I also checked the soil and I noticed that is was semi-dry. Since I noticed the withering/dead leaves, for the past two days I’ve been watering them every other day but I’m afraid of overwatering.

After watering, I check the soil and its semi-moist but the next day it feels somewhat dry again. Maybe I’m watering too little? Is there anything I can do to help them recover? Thanks!

My reply:

Hi Thomas
it sounds like Read more »

Newly Planted Knockout Rose Problem

Ashley writes about her newly planted knockout rose problem: “I planted my double knockout rose bush 2 days ago and the leaves are drooping and so are the rose buds. I have clay soil so I dug the hole and planted my rose bush and filled the hole back up with garden soil and “black cow” (brand name) manure. Did I do something wrong. I have watered everyday also”. Read more »

Transplanting Knockout Roses

transplanting knockout roses

I received a query about transplanting knockout roses this week from Carrie. She asks: I have three knockouts growing nicely over the past years.  I’m redesigning and I want to relocate them within my garden.  What is the best way to move them – and, living in Virginia, when is the best time?

Hi Carrie, I have been asked a few times when to transplant knockout roses along with how to transplant roses in general, so I have written this article to cover the basics. Transplanting roses is not as difficult as people assume, and you should get good results by following the instructions below. Read more »

Scraggly-looking Knock Out Roses

Amber sent in this question which I answer below.

Q: This will be my second year with my ko roses. The problem I’ve been having is they are all scragly, only growth mainly at the top of the branches. I pruned them a little during the growing season but they didn’t fill in.They were repeat bloomers and are still producing. I want a prettier fuller bush. What can I do to make this happen? ( Panama City Fl.) Read more »

Winterizing Knock Out Roses

Paula from SE Michigan writes

“I recently purchased and planted two Blushing Knock Out roses. I live in SE Michigan and the nursery told me to plant them right away, which I did this week. So far, they look great. Here’s my question: I ordered one more which is not scheduled to ship until Nov. 9 and am wondering if I should also plant that one or keep it inside until spring? Also, should I cover the other 2 for the winter (I put a lot of mulch at the bases)? Thanks in advance!”

Hi Paula

Nov 9 is going to be another month away from when the nursery told you to plant your knock out roses “straight away” so you might be pushing it. I’d play it safe and keep it in your garage until spring. Water it once a month and it should be fine.

SE Michigan is considered USDA zone 5 (some say USDA zone 6 now due to the climate getting warmer) and from research I’ve done there are mixed opinions about whether to protect knock out roses in winter in zone 5; some folk Read more »

Roses and Gravel Mulch?

roses and gravel mulch

Cindy wrote in asking about using gravel as a mulch around rose plants:

“I was thinking of planting a line of knock out roses along the edge of the woods on my property. I wanted to line the bed with white gravel instead of mulch. Do you see any problem with this?”

Personally I wouldn’t use a gravel mulch around roses. The reason being is that they absorb heat and can get very hot in summer and adversely affect the the fine-haired feeder roots that sit close to the surface as well as make the area under and around the rose hotter, resulting in increased transpiration (water loss through the leaves). Read more »

Roses and Liquid Seaweed

A visitor to my site, Kristi, wrote the following comment and I thought I would write a new article about the benefits of seaweed in the garden. Kristi writes: I am a newbie so I am finding much help from this site. Could you please elaborate on the seaweed spray? Thanks. Well Kristi here is my response to your query.

What Liquid Seaweed Does For Your Soil and Plants

Seaweed is rich in potassium, minerals, trace elements and naturally occurring growth stimulants. It is one of the best things you can use in your garden and I use it on everything; roses, fruit and vegetables, annual and perennial flowers; they all benefit greatly from the addition of liquid seaweed as part of their regular care.

You can use diluted liquid seaweed in a watering can and water it into the soil at the base of your plants; or hold the watering can over the whole plant so it waters the leaves as well as the soil or just use it as a foliar spray on the leaves.

Liquid seaweed helps promote flowering, fruiting and robust health on every plant it’s used on. It stimulates root growth, and stronger root growth means better water and nutrient uptake to the plant from the soil. It also stimulates the production of more beneficial soil micro-organisms.

Read more »

Black Spot on Roses

black spot on roses

black spot on roses

With all the wet weather Sydney has been experiencing lately, it has provided perfect humid conditions for the development of black spot on roses. I recently got this question from a reader and thought I would answer it here.

Q: have found black spot on my roses and have cut all the bad leaves off, now some one told me that soapy water will help this and affes can you please tell me pretty new at the game but love my roses. Read more »

Bare Root Roses – What to Look For When Buying One To Plant In Your Garden

bare root roses

bare root roses

Roses are such a popular plant in the home garden, with their beautiful blooms and fragrance, but do you know what to look for when buying bare root roses to plant in the garden?

Gardeners will happily buy bare-root roses to take pride of place in their garden. They painstakingly prepare the soil, plant  and water their newly purchased bareroot roses and are then aghast when nothing happens at the start of the growing season. Not one leaf bud shoots out from the branches. They usually put it down to their lack of skill in the gardening department but more often than not, they have bought a bareroot rose bush whose roots have dried out and created a dead rose bush. So they have basically planted a rose bush that was dead to start with. Read more »

Pruning Roses – What’s All The Fuss?

Pruning Roses

Pruning Roses

Some folk are scared off by the thought of pruning roses, thinking that if they don’t do it right, don’t cut it at the right angle or to an outward facing bud that they’re going to somehow damage their roses. This type of thinking takes the joy out of growing roses. Read more »

Pruning Knock Out Roses

Knock out roses are gaining popularity because they are easy to care for and fairly disease resistant. One of their selling points is that they are “self cleaning” meaning the petals fall clean, and while that may be true this article discusses why you should regularly deadhead them and explains the simple process of pruning Knock Out roses annually. Read more »

Knock Out Roses – How To Plant Them

Knock Out roses are supposed to be one of the hardiest, and disease resistent roses available at the moment. In order to keep them disease resistent you want to plant them in an environment that’s conducive to their health and vigour. Follow these steps when planting  Knockout roses and they should reward you with disease free growth and prolific blooms. Read more »

Knockout Roses – What You Need To Know About Them


Knockout Roses seem to have taken the rose growing world by storm as one of the easiest, trouble-free rose plants to grow. Apparently this AARS award winning rose is the most widely sold rose in North America due to its hardiness and versatility.

This rose was hybridised by Willian Radler and introduced to the world in 1999. It’s a floribunda rose that grows to about 4ft tall (1.2m) and as wide, forming a small compact bushy plant. Read more »

Lavender Roses – My Top 5


Just about every lavender rose seems to have a fragrance, and if you grow your roses for their fragrance in additon to their beauty, as I do, you’ll want to make sure that one of the following rose plants finds a place in your garden.

Lavender Roses

Leading the field is one of my very favourites, Blue Moon. Not only is the colour of this rose bush enchanting but the fragrance is exceptional. It’s a hybrid tea rose that grows 135 cm (4ft 1/2ft) tall, with large, full petalled blooms that last well. It is no wonder it’s been one of the most commercially successful lavender roses. Read more »

Rose Society – Where To Find One And Why You Should Join

It’s such a pleasure to get together with a group of people who share the same passion as you do. Joining a rose society gives you an opportunity to connect with likeminded folk who share your satisfaction of growing roses and who enjoy exchanging various tips and ideas.

Your partner or family members may not share your enthusiasm for rose gardening and it’s good to be able to talk with others who “get it” – the joy and pleasure you experience while pottering in and around your garden. Read more »

Growing Roses – Don’t Kill Them With Kindness

Picture this: You enjoy growing roses and one of your beautiful rose plants is starting to turn up its heels. The leaves have been yellowing and falling and the shoots are starting to die off.

You don’t know what could be the problem. You give it a good watering every few days, but it doesn’t seem to be helping – in fact the rose plant just keeps looking worse.

It is often at this stage that you think maybe it needs some fertilizer. So you go get some rose food and spread that generously around the base of the plant. STOP. This is the worst thing you could do for it.

Read more »

Rose Care – Black Spot on the Roses

This week in the rose garden I discovered some black spot on the leaves of a couple of the rose plants. Part of rose care is managing rose diseases as soon as they appear on the plant. We’ve just had 3 days of rain here so there’s a lot of humidity in the air. The perfect condition for black spot to make its appearance. Black spot is the scourge of rose gardeners who grow roses in humid coastal climates like Sydney. Read more »

Roses – How Much Sun is Enough?

Roses need an open sunny position to grow best. A minimum of 5-6 hours a day of full sun is required for their optimum growth. Roses produce a prolific amount of flowers which take a great deal of energy from the rose plant. In order to keep replenishing this energy the rose needs Read more »

Planting Roses – what do you add to improve soil?

Soil preparation is important if you want healthy robust rose plants that bloom prolifically.
There are two ways to go about improving your soil for planting roses and they depend on the amount of time you’ve got before you plant them.

If you are planting roses right away.

If you are planting your rose bush right away, the only thing you want to add to the soil at planting time is Read more »

Before Planting Roses – best to check pH and Drainage

Before planting roses, it’s a good idea to check the pH and drainage of the area you are going to plant in. If you want healthy robust rose plants that bloom prolifically you’ll want to make sure these two areas are part of your pre-planting preparation. A sickly rose plant is a beacon to pests and disease. They just seem to know when a plant is doing poorly and zoom straight in for the kill! What goes on above soil level is a reflection of what’s going on beneath soil level, so it’s the smart rose gardener that takes the time to check the soil pH and drainage Read more »

Aphid Control

aphids on roses

There were lots of aphids on the rose tips and buds this week in the rose garden. The soft, sappy new spring growth on the roses brings them out in droves. 

Aphids on roses can cause Read more »

Rose Plant Myth

bridal pink floribunda

Roses are probably one of the most widely grown plants in the home garden – whether planted in a bed of their own or planted in amongst other shrubs. They are also one of the best loved flowers throughout the world – they are certainly my favourite – their beauty, form and fragrance is hard to beat.

There is a myth going around that roses Read more »