Any article that promotes “foliage feeding” is immediately suspect. I would think the horticultural oil is likely the component that does the heavy lifting in that scenario. Also, growers should be careful spraying anything that affects pH, as the material will inevitably end up in the soil and has the potential to change your soil pH, possibly in an undesirable direction.

Did he say he sprayed every two months? That doesn't seem often enough to protect new growth, or did I hear wrong?

Thanks for posting this nice garden tour with beautiful roses ...

Paul, I guess that in my case decreasing my soil PH would not help since I have a crappy caliche soil.

Ragna, you’re welcome. I thought some of you would enjoy those videos. I think a lot of the information they share is “applicable” to many Texan “conditions “. They said they spray every 10 days.

Omar

Here is your answer Omar,

https://www.woolworths.com.au/shop/productdetails/75201/mckenzies-bi-carb-soda?googleshop=true&googleshop=true&cmpid=smaf014&cvosrc=ppc.google-lia.75201&cvo_campaign=&cvo_crid=248938554885&ds_rl=1260749&gclid=EAIaIQobChMIjbrSi9Dy3QIVVwwrCh3iPQpREAQYAiABEgLOt_D_BwE&gclsrc=aw.ds

Also, see:

http://www.abc.net.au/life/gardening-australia-recap-bouquet-loads-of-roses-talk/10337876

David, thanks but that it's just Sodium bicarbonate. The guy from the video said potassium bicarbonate. I don't think it's the same thing.

Omar

AH -- No. And if he confuses the two, I would take his advice with a large grain of salt ...

As they say, the proof of the pudding is in the eating. I don't know if some of you didn't watch the video, but they have been growing roses commercially on their property for decades, and they certainly look healthy, which is no mean feat in Queensland.

As for potassium bicarbonate, this is what I read 'Potassium bicarbonate is a chemical analog of baking soda. It is used in wine, club soda, and pharmaceutical products, so one can feel pretty safe about using it in the garden.' He fertilises separately with a low nitrogen fertiliser.

As Paul Barden said earlier, it does change the pH - the chap says that's why it works - the pathogens don't like it. But they spray every 10 days, I think he said, during the growing season (except when they 'force' dormancy presumably), and all is looking remarkably good.

Back when I used to spray my roses, I used a product called 'Remedy' made by Bonide. It was labeled for several rose fungal diseases and was based on potassium bicarbonate. The potassium bicarb is supposed to be gentler on plant tissue than sodium bicarb. I believe it is still available by mail order.

Eventually I decided instead to grow roses that were reasonably healthy without spraying. I live in a semi-arid climate where this is a realistic approach, provided one is willing to remove any roses that don't live up to your standards.

Went looking online for it just now and came across a product from Dow also called 'Remedy' that is apparently an herbicide. You certainly would not want to confuse the two.

Vesfl, one can grow Lamarque in zones 5b/6a? How wonderful! It is a gorgeous rose. I spent my early gardening years in zone 6 western Pennsylvania, and carefully avoided the teas and noisettes. I have seen tender roses such as Lady Hillingdon Cl grown on stone walls in England. If I ever live in a cold winter climate again, I will do my best to have a stone wall (or brick) around my garden. Who knows? Maybe I could even plant a pomegranate tree.

Rosefolly, sorry that I wasn't clear enough - I wasn't sure if the OP is from Australia or the states, so when I said "here" I meant in the warmer zones in the US. I've seen it in Louisiana and Texas, absolutely gorgeous. I'm with you about tenderness, but I'll still try 'Gloire de Dijon' in my area, will plant it in the warmest and sunniest spot, right next to the south-facing wall. I know it's likely to fail, but... oh, well. We all have our zone-pushing 'sins' once or twice (or thrice :-)).

You can get potassium bicarbonate here:

https://www.amazon.com/Potassium-Bicarbonate-Powder-BulkSupplements-Supplement/dp/B075GVLR27/ref=sr_1_4_s_it?s=hpc&ie=UTF8&qid=1538930965&sr=1-4&keywords=potassium+bicarbonate+bulk+supplements&dpID=41DXUThA78L&preST=SX300_QL70&dpSrc=srch

Now that makes more sense to me. You had me wondering just how much climate change is taking place back east.

I did not think that even the hardiest of Teas would grow in a climate colder than 7, and most are happier with 8.

In my yard, the hardiest teas can SURVIVE in zone 5 with a lot of protection and pampering (Maman Cochet being the best of these) but they certainly don't thrive and I wouldn't recommend them outside of the warmer zones. I haven't tried Lamarque but I rather think it's not among the toughest of the teas.

Cynthia

Cynthia, that sounds like an awful lot of work.