Rose stems turning black

[chimukli]

I got roses last year from HomeDepot. They were good last year . This year from may i have noticed roses growth has slowed down considerably. Stems have started turning black . roses are outside the house . full to partial sunlight . first i noticed leaves dissapeared . slowly stems started turning black. i have started feeding miracle-go once a week and spraying bayer natria neem oil spray from end of may once a week. i water them almost every day .
hibiscus, lily planted not too far seem unaffected . they are doing good .
please advice how can i bring them back to life.
very sad to see roses lifeless. They are of knock out variety.
location princeton nj 08540.

 

[Sheal]

Welcome chimukli.

The ground that the roses are in looks quite wet which also suggests that perhaps that area gets very little sun, neither of which will help your roses. Feeding them miracle gro will not be enough either.

Roses are hungry and thirsty plants that love the sun. If yours are in shade I suggest you move them to a sunny position in your garden, one that gets at least three hours of sun a day. They will not appreciate soggy ground although they like to be watered regularly. Roses need feeding regularly, two or three times during the growing season and they would appreciate well rotted horse manure if you can get it. There are alternatives.......I use chicken manure pellets because I can't handle the weight of manure, blood, fish and bone is another good feed, or there's specially prepared rose feeds available.

Most of the roses in the pictures have been pruned extremely short, were they like this when you bought them?

 

[Greenhorn]

I agree with Sheal. Roses typically don't want that much moisture and they do want sun. I have mine on drip and the sub-soil is generally damp to almost dry back to damp with the surface mulch typically dry. As an FYI they don't like moisture on the foliage much either. I just mulch around mine, much like yours, but drier of course . As far as feeding, it's not organic, but I've had very good luck with Bayer 3 in 1, it's Fertilizer, Pest and Disease.

 

[Ashanti Duggins]

Sounds like your rose stems have some kind of fungal disease it escapes me the name of the fungus that causes this to happen. You may have been over feeding and caused it's soil may have been to mushy.

 

[TNichols]

I have a similar issue. It is early in the year but I do not think water is the problem. Fungal issue sounds likely. Will update if find more.

 

[Sheal]

Welcome TNichols.

Pictures of your plants would be helpful please.

 

[Flatlander]

There are several reasons that rose stems can turn black.

In a few areas, it can be caused by a kind of bee. Relatively uncommon, so that can probably be discounted.

There is a virus. Rose Canker. This is easily recognised by cankers forming on the stems. It enters mostly from pruned surfaces and travels downwards. To prevent the virus entering, some seal the surface with either PEG, or a 50/50 mix of white glue and water. Having said that, some cases of it travelling upwards from the root have been recorded.

The basic cause though is probably as @Sheal said. Over watering. Although roses do like plenty water, they dont like having "wet feet." This, combined with over pruning, as these seem to have been, provides all the conditions for unhealthy roses. That includes the virus I mentioned above.

Of course, black stems do sometimes happen when the roses are subjected to freezing.