Marigolds are famous for repelling bad nematodes in the soil, so I am not surprised that they also repel above ground pests. Thanks for the tip!

Jackie

I've read for years to plant marigolds around your tomatoes to keep the tomato worms away. A worms a worm so I guess that's why it seems to work for roses too!

Thanks for this, Jim. Heirloom Roses mentions companions for pest control on their page for companion plants with roses. It wouldn't hurt to grow a few of these.

Here is a link that might be useful: Heirloom Roses-Companions for Pest Control

In different conditions, but it seems like when I add a new rose to a new location (one that did not have roses before) I seem to have a horrible outbreak of rose slugs. But soon the predators seem to discover they have a new place to feast and the slugs seem to reduce or all but vanish.

Hard to be patient, but no spraying for slugs for me, on the other hand marigolds would be fun to plant too

Rose slugs have started getting on roses that are surrounded by Marigolds now.

So the Marigolds are NOT fully repelling the rose slugs.

Much less damage this year though...

I will try planting Marigolds next year again to see what happens.
I'll let everyone know...

This post was edited by jim1961 on Thu, Sep 4, 14 at 12:58

Thanks for the update -- I enjoy your experiments & the accompanying photos tremendously. My rose slugs only visit for about a month in early spring but they do a terrific amount of damage in that short time.

Jim, thanks for sharing your experiment.....marigolds will be added to my spring list.

How is your wasp supply? It's rather interesting to watch them hunt. They fly over a leaf, drop down to fly under the same leaf, then move over to the next leaf and repeat the process. Someday I may be there when they find something, but so far I've just seen them hunting. They may like the marigolds, and stick around for lunch.

mad_gallica,

This time of the year the wasps and yellow jackets are more plentiful than our previous months...

Actually I was very lucky to capture this picture a couple years ago mad_gallica...

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I had bad rose slug damage for a few years, but then the Preying Mantis moved in. Damage has been reduced, oh, about 99%. I can probably find a leaf somewhere out there with a few holes in it, but it is going to be a search.

I have not seen a praying mantis in many years hoovb. We once had them and they were plentiful at one time here...

I mixed a few squirts of Dawn (blue) dish washing soap, a teaspoon of baking soda and water in a squirt bottle, and sprayed my leaves. I was really not expecting great results, and it's really been an ongoing battle all summer, but it worked! It was a pleasant surprise. I guess the slugs can't attach properly because the soap makes the leaves slippery. I'm not exactly sure what the baking soda does, but it did not harm my plants at all. I got this tip from a neighbor, who is an accomplished green-thumb.

The soap probably killed them anteakfreak...
One product that works to kill rose slugs is safer insecticide soap... Wet the bottom and top of leaves basically the entire rose bush as I have seen rose slugs crawling on the canes...

This post was edited by jim1961 on Fri, Sep 26, 14 at 13:29

One caution about interpreting results--mama sawfly does not lay eggs on all roses equally. She likes glossy-leaveed climbers with wichurana heritage, and certain others. So it is normal for some plants to be more heavily damaged than others.

Michaelg, that's why I'll be testing out Marigolds for the next couple years or so...
Since I already know rose slugs can cause moderate to serious to the type of roses I have here right now...
This year was great for once hardly any damage at all!...
But yes further testing is needed as it is possible it was other factors that caused the RS decline...

Well I removed some Marigolds from around 2 Double Ko roses about 1.5 months ago.

I just checked for rose slug damage on them today and I found lots of rose slugs on those 2 bushes and some damage...

I checked bushes of the same type with Marigolds surrounding them and found still very little damage and I could find no rose slugs on them...

So next year every rose bush here will be surrounded in marigolds to see what happens...

Pics I took today:

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These roses which are the same type have hardly any damage at all!
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Took more pics today as the experiment continues....
So far things going great for the roses with Marigolds!
I'm very happy as I can still report good results! And hardly any rose slug damage at all! :-)

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Above in my last post I just updated results on Roses wth Marigolds.

This post has the dark side! Roses WITHOUT Marigolds which are the same type of rose bushes are getting slaughtered by rose slugs!
Leaves are being stipped off worse & worse each passing day!

Just now took these pics! You can see 3 Rose Slugs in the one pic..

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This year is quite different than most here... We usually have a wet sloppy rainy Spring and decent amounts of rain throughout the summer months.

This year so far we are in a Spring drought....

Rose Slugs came early and were here in late April to early May... So they were already on the roses before I got to plant Marigolds this year... (Planted Marigolds May 15th)... THEN we had a freeze May 22nd which killed our Marigolds so I had to replant...

Anyhow Marigolds got replanted and now lets see how much rose slug damage we get the rest of the growing season...

( The common Rose Slug is here right now but they will be gone soon.)

(Then our Curled Rose Slugs will show up in May/June and they will be here until frost..)

Jim, it might be that marigolds repel the adult sawflies, and they don't lay their eggs near the roses, thus no larvae hatch to eat the leaves. I'd be interested to see if planting marigolds after the larvae appeared have an effect.

:-)

~Christopher

Our drought ended today as we got flash flooding... Our rose slugs may of got washed away...

I planted Marigolds around roses again this year and we have had only minor RS damage so far... So we are very happy and will continue the practice...

I did discover that the French type with single petaled flowers that we planted out front stink 5x more than the Marigolds I'm using elsewhere and they attract more Predatory Wasps etc... So I'll be making some minor changes next year...

Our propery is one big stink cloud...lol

Sometimes good things must come to an end! lol

Our Curled Rose Slugs are just now starting to attack our roses in spite of all the Marigolds planted here...

I watched curled rose slugs devour our neighbors roses since early June... I had no damage at all from Curled rose slugs up until yesterday so I figured the Marigolds are doing there job!

BUT today I noticed a decent amount of damage in a short period of time on some of our roses...

It was great while it lasted! lol

But the Marigolds did hold them off for a long time for whatever reason...

I have the green worms in spring from the winter moths, but I think the birds get most of them.

I'd really love to find something to control midge without spraying but I don't think it's possible.

Rose Midge are a pain for sure altorama! Hope you find a solution...

Rose Slugs started causing some damage for a few days then nothing...I inspected all the roses today and could not find any rose slugs... I checked the neighbors and I found quite a few on her bushes SO I'm going to continue using Marigolds as they are helping in my opinion...

Some grasshoppers still on some of our roses but not many so just letting them alone...

Jim I have enjoyed reading about your experiment. Good for you. You flower beds look great. I may have to invest in some marigolds for next spring. Thanks.

Valerie

Updating:

I have recently been finding some 1/2" curled rose slugs here and there. But Rose Slug damage is low this year again. Esp for us having two different types of Rose Slugs here and the Curled RS being here from June until now (Sept)

I notice a lot of other areas only have one type of rose slug and they are only there for a shorter time period...

So all in all I'm happy! lol

I'll report back next year....

Good investigating, Jim!

And marigolds are so pretty!

Carol

For heavens sakes never plant broccoli any where near your roses. I might need those marigolds next year. The neighbor had broccoli plant near the roses. After volunteering to remove them when they where past their prime. I know now what was making the holes in the leaves. Thousands of rose curled slugs / broccoli slugs I can only imagine how many eggs where laid. After removal needed to get the ones I missed off the roses.

On the other hand if a person always has many rcs. Perhaps planting a few brocolli plants in an out of the way spot would keep them away from your roses.

Jim, thank you so much for the rose slug/marigold data. I have them throughout spring-summer-fall. They especially love Colette (Meilland) and Evelyn (Austin). I'll be on the watch for pony pacs of marigolds next year, but I think damage has begun by the time our big box stores offer them :-(.

Interesting concept about the broccoli Patty... Were the same RCS eating broccoli eating your roses too?

Can you take a clear closeup pic of one Patty?

I wish I could Jim but they were murdered I'm afraid to say. I laid the plants on a tarp chopped up the plants and stuffed into dark garbage bags to bake in the sun. They were exactly the same as your photo. The same ones I get which eat large holes in my rose foliage as they crawl upwards to feed on the buds. This will continue until I find them or they are eaten by something. Oh and while bagging I found the toads that were feasting on them. So I feed the ones still on the tarp to the toads and apologized for taking their supper.

Here's a Curled Rose Slug I found in a bloom the other day... When I deadheaded it went in the trash...lol

I see toads once in awhile here but not often...

I'm sorry it was mad's photo above.

I don't see any photos from Mad in this thread?

By the way our Marigolds are still going strong...Took this pic recently...These things bloom heavy non stop...

Jim - did you repeat your Marigold experiment this year? If so, how did it go?

Yes I did repeat my Marigold experiment...Last two years I had other flowers mixed in with Marigolds/ This year I only planted ALL Marigolds...Results: Most of our roses have hardly any rose slug damage right now.... But we do have 3 roses still being eaten by rose slugs but the damage is still on the milder side at this point in time ....So?...

So next year I'm going to mix other plants in with Marigolds like before... Plants that will attract more Predatory wasps etc. that will feed on the rose slugs...

I also had finches etc. landing on our roses to help eat rose slugs... I feed and keep water here for birds so they stay...

SO....I think a large part of the secret is attracting Predatory wasps etc, and birds to feast on rose slugs.

Whether or not the stinky smell of Marigolds helps in any way I still really have no idea...???

All in all had 3 straight seasons of not much damage so will continue the practice...

How very interesting! What type of Marigolds do you plant? The short French types that have flattish flowers, or the tall African ones with pom-pom shaped flowers?

Short French...singles attract more wasps etc....I have doubles & singles flowered Marigolds... (like in tall pot) Other lower plants are orange zinnias...

This is the worse damaged bush but you can see its only mild RS damage...I do not pull off any Rose Slugs from our bushes... I let them eat because I want to achieve a balance from nature... I want to enjoy our roses and not have to spend a lot of time pulling off Rose Slugs...lol

Jim - that is a great experiment. I'd love to give it a go, but I will have to come up with a way to keep the groundhogs from eating the Marigolds. Wouldn't you know it, the French ones are their favorite. LOL!

PS:

Did you ever hear of "Stinking Roger"? Supposedly, it's the most smelly of Marigolds. I am quite intrigued by it. The only two things that make me feel a bit cautious are: 1) it is considered a noxious weed in some places, and 2) it seems to be huge.

I never heard of a Stinking Roger Marigold eweandbee...To large and they might overshadow the rose bushes... I like them to stay in the 10" high range...

Just took these pics... These curled rose slugs hang around until frosts here... But the crazy thing is we hardly had any RS damage this year...This guy is having a late season snack I guess...lol...These curled RS are about 3/4" long or so and can munch a lot of leaf area...I like how he is sleeping between two branch stems..Guess they gotta sleep & eat too... Back in 2010 these guys entirely stripped one of our rose bushes of all its leaves...Since then I've been planting Marigolds and other flowers that invite wasps and birds etc. into our yard...So these days I just let RS on the bushes to feed the wasps, birds, etc and that seems to be working...

So all in all another good year here... :-)

This is the rose bush the RS is on and as you can see only a few leaves have been munched...

Thanks Jim very cool info! I might have to try this I have these on some of my bushes right now.

Well after years of growing Marigolds then years of NOT growing Marigolds... I came to the conclusion there was NOT much difference in population of Rose slugs...

So these days I'm just enjoying growing other types of flowers and have not grown any Marigolds for awhile...

I continue to invite lots of birds into our yard...Providing a birdbath etc. And plant different types of flowers that are attracting predator bees... These days I do not even bother picking rose slugs off bush or spraying for rose slugs...For now anyways, it seems I have achieved a balance with nature...

Good to get an update, Jim. I was reading through this post, and starting to think about finding some Marigolds that aren’t orange! Lol

One thing that I’ve noticed with the rose slugs here is that the more stressed a rose is, the more rose slug damage I see. My roses that are planted in less than optimal places have far more rose slug damage than the ones that get better sun and water. The ones in too much shade, or blistering sun against the SW side of the house have more of a problem with rose slugs than the rest. I guess they go for the ones that are struggling at my house. Lisa