I’ve planted a number of the big-name plums over the years. (Shiro, Green Gage, Santa Rosa and many others.) Over 12 years all my plums got black knot and had to be cut down. But…I’ve never tried the Au Rosa.
I had heard Au Rosa is very resistant to black knot. Do you think it would do OK here in black knot hell?
Thanks!
That’s certainly one way to cure Black Knot. I’m going to let my Methley go to the bitter end rather than cut it down though. How bad did your trees get before you cut them down?
Don’t know anything about Au Rosa but I will be watching this thread. My thinking is that all Japanese plums are at least somewhat prone to BK.
Suppose to get down to 32 here tonight. Usually gets colder than the forecast.
I’ve had AU Rosa for about five years. As of now I haven’t seen any Black Knot on it.
I have AU Rosa and Shiro trees here in southern middle TN.
I have added grafts of 7 other varieties to them.
Going to add a couple grafts of AU cherry plum to them soon… that will be 10 varieties.
These jplums have not had black knot at all and are starting on year 3 now.
I had other varieries of jplums started in 2002 that lived 13-14 years then died… no sign of black knot… one died one fall… the other the next fall.
I started 2 eu plums in 2018… rosy guage and mount royal.
My RG got black knot twice on a single limb on different years… I removed the limb. Then the next spring after… while it was leafing out it got some type of wilt and died.
My mount royal was planted right next to it and has never had BK and is still thriving.
My worst problem with plums is their early bloom… almost always lose entire crop to late frost.
I have fruit set now on my jplums… we are at 34F this morning so far. It often drops 1 more degree about sunrise.
The rest of my 10 day forecast has lows in the 40s and 50s.
This could be the year for plums here. Hope so.
TNHunter
All my plums were covered with knot. I used to get plums almost every year, although Green Gage took 9 years to produce its first crop.
The trees were covered with it. Maybe if I had caught it early and knew what to look for, I could have cut the section down. But I didn’t know what it was until it was widespread.
I can’t say when they got the knot. I was not on the ball. I would just let trees go and pick the fruit. Maybe I thought it was damage from cicadas first. We had gone though one of those big cicada cycles. Then I looked it up and by that time all the trees were covered with it. I had to cut them all down after 12-13 years.
I could have let them go. They kept producing fruit. But was worried about my other trees. I will see if I have any photos.
Can’t believe you’re warmer than me. I’m 45 minutes south of Birmingham and it was 29 this morning
@sgld … our temp did move on down to 32-33 just as the sun came up… we got some light frost on the grass and had light frost on my truck windshield.
Hoping it was not cold enough to harm plum fruit already set… or pear blossoms open now.
The sun is out 51F now.
My next 10 days the lows are in the 40s and 50s. Looking good.
I took most of the protection off my CH Fig… easing it out… getting some sun on those buds for wake up.
This last pic is not buds flowers fruit…
But what gardner does not enjoy the looks and smells of a freshly turned compost pile.
TNHunter
The growths seem to adhere on the outside surface of the bark.Are they firmly attached?
27 degrees here this morning with some patches of snow on the ground from overnight flurries. My Methley and AU Rosa are toast again for another year. In the new Zone 7B but have yet to see them produce 4 years in a row.
I planted an AU Rosa two years ago. It is about 50 feet from a huge black cherry in our neighbor’s yard that is covered with black knot. So far, so good - no sign of it on the plum tree.
27 is not that bad with the wind we had. Maybe 25 percent kill.
I would be happy with 25% - it would be nice to actually eat a couple this year.
I know wind can prevent temps from dropping as much. Would windy conditions (and the lack of frost formation) be less harmful in your experience?
I see lows 5 to 10 degrees lower than forecast when everything is still. When windy, the forecast is pretty accurate. Being quite dry helps with the frost damage too IMO.
I feel your pain on the temps being typically colder on still nights than forecast by the NWS. My theory is that the NWS forecasts for the mountains of WNC are one size fits all made with Asheville in mind. Most of our county is situated in a basin ringed with 5000ft mountains on all sides - we get tons of cold air drainage off of those slopes which results in big drops in temp on clear and calm nights.
Anyway, just checked the plums and the blossoms along with the nascent fruit all brush off with ease. Another year with no J-Plums. Thank goodness my apple, persimmon, and cherry trees all know to stay dormant until later in the spring!
When does Au Rosa bloom compared to your other Jap varieties?
