Organic rose black spot remedy

Jason-3

Hi all a couple of my DA roses have devolp d early BS. I'e historicaly used chemicals to treat with tge results been fairly poor. Ive seen lots of natural remedies neem oil, baking powder, milk!! Just wondering if anyone has a remedy that is tried and tested and works as I realy don't want to start removing canes that are full of buds

Nollie

I’m in a similar situation with my DA’s Jason - most suffering really bad blackspot - possibly due to very changeable weather here over the winter, but they were recovering a bit after some good dry weather and the whole hygiene shebang.

I can’t recommend a tried and tested solution as I am both fairly new to rose growing and experimenting, with milk solution at the moment, but I can caution against neem oil...

I did a first application of neem solution and it burnt all the leaves as it suddenly got sunny and warm. It left a nasty film on the leaves which won’t wash off and a few weeks later, are all withering and dying to add to the BS nightmare. Others might have more positive experiences with neem.

Just returned from holiday to hear we had storms and torrential nonstop rain for over a week (poor housesitters!) and so to add insult to injury my roses are looking extremely battered and bruised with all initial BS recovery now lost  

I suspect there isn’t a tried and tested solution that is guaranteed to work, interesting you say the chemicals didn’t work as that was my fallback if the milk didn’t do anything...

 

Lizzie27

I was going to experiment with Sulphur powder which I believe you can get online on the grounds that roses didn't get as much black spot where coal fires were burning, but unfortunately just didn't get round to getting it. Has anybody else tried yet?

Jason-3

I'e read a lot more re this matter and their dosent seem to be any hard evidence that anything realy works, except a hard prune and disposal of all the material. So I might try a few methods and report back. Going to try and the milk method over the next few weeks
I'e also noticed that as the plant has grown realy tall it has some rocking,which naturally won' help with blight! ! So rather than dig up I'll mulch as much as I can and then dig up the rose when it' dormant

Grub2

It's certainly true that since the burning of fossil fuels declined, the deposition of sulphur reduced.
This has had an effect on agricultural crops, particularly brassicas for more than 20-30yrs now, with not only a deficiency of this very important nutrient affecting productivity, but also a loss of the benefits of sulphur as a fungicide assisting in the control of a range of crop diseases.
The deficiency has been remedied in farming largely by not only adding sulphur to fertiliser, but also by using farm manures (dung) which contain significant levels of sulphur.

Now on to roses.
I probably have around 100 roses in the garden, almost half DA.
When I plant a new one i incorporate a mixture of soil with large quantities of well rotted farm manure. Every year after that I mulch with more manure. I also spray once early with roseclear.
At the moment they all look vibrant and healthy with only the odd leaf showing any sign of BS, including a cheap job lot of roses purchased earlier in the year from the almost dead discount section in the local garden centre.

Sorry to be so long winded, but I really just wanted to advocate the use of manures not only as a source of nutrients, but also as a source of sulphur to assist, in this case as part of a regime to keep BS at bay.

Jason-3

Good posts and ideas folks. I always mulch my roses with 50/50 mix of garden compost and rotted manure. Id love to use fish blood on my roses as they seem to thrive, but can'  due to ongoing fox and rat problem