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Staten Island, New York Leeann79 Aug 13, 2019 5:55 AM CST |
Right after spring bloom my roses all together started showing black spot, I cleaned up and treated plants. But now there are so many different symptoms of fungal and bug infestation that I've been treating them for both, here is some of the list of symptoms. There are unopened blooms that turn brown or stunted and deformed. Some leaves turn bright yellow with larger green spots, some are curled, some are pale with teenie brownish on the underside of leaves, and some are heavily chewed. I also noticed a weird big growth at the base, slightly below the dirt of my New Dawn climbing rose. There are just too much to list. I'm just too annoyed with constantly cleaning. and treating. Please help Pic#2 is my Amethyst Fall Wisteria, which never bloomed and leaves are a mess too. Pic #12 is the growth at the base of the plant ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
gardenfish Aug 13, 2019 8:37 AM CST |
Hello, I will try to help. What I see in nearly all your rose pics is the dreaded "B" word, black spot. I deal with it every year; it is chronic in my area; eventually nearly all roses here get it. It is not totally curable, but it can be managed by certain routines. They are: totally remove and replace mulch every year, spray weekly from early leaf break (Jan or Feb here) to first hard frost, daily remove infected leaves( some people disagree with this but it works for me), switch fungicides every two years or so, and grow varieties that have some proven resistance to it. The semi- circular holes on the leaf margins are made by leaf-cutter bees, they are harmless, this is a cosmetic problem . Japanese beetles will eat the buds and skeletonize leaves; I have them for the first time ever this year. I'm sorry I can't help you with the wisteria, no clue. ![]() ![]() “ Be kind whenever possible” 14th Dalai Lama |
Name: Jim Central Pa. (Zone 6a) jim1961 Aug 14, 2019 9:59 AM CST |
I see Blackspot and other fungal diseases..And maybe insect damage on that 2nd pic...(white areas) |
MargieNY Aug 14, 2019 12:39 PM CST |
I am on Long Island and experiencing similar symptoms on my roses too. If you haven't applied a fungicide recently, try and do it today as we are suppose to begin getting more humid weather for several days starting tomorrow. I know I can help you and I will write to you later tonight - I am busy right now spraying (organic) - just taking a break. Keep the faith... Observe, observe, observe We are fortunate to "see" & appreciate nature in ways others are blind. |
Coastal Southern California (Zone 13a) jerijen Aug 14, 2019 1:54 PM CST |
I suspect there may be some spider mites, though the photos aren't crisp enough to show the leaf undersides that clearly. You might check this out: https://rosemaniablog.wordpres... Insecticides will not kill spider mites, as they are not insects -- they're arachnids . . . like spiders. So you would need a miticide ... but personally, miticides are just a step too far for me. I prefer a !!!BLAST!!! of water, UPWARD, from below the foliage. That will wash the little creeps to the ground, where they die. And, yes, you do have some blackspot. As you add roses, or replace them in your garden, look for cultivars that are blackspot resistant -- spare yourself a lot of work and angst. |
MargieNY Aug 14, 2019 8:37 PM CST |
I was told many years ago by a gentleman who has a garden here on LI with over a 1000 roses, "If you want to grow roses on LI you have to spray". At that time, I was bound and determined to prove him wrong and so I initially purchased many Kordes roses that were specifically touted to be disease resistant. It has been my experience after acquiring over 138 different roses, not counting duplicates, that the gentleman was right. I believe the the fungus is everywhere - it's in the air. I did notice that some roses as they matured (3 yrs.old) they did get the black spot to a lesser degree. Almost all of my roses recover quickly. When you have high temps AND high humidity as humans, we have to watch for heat exhaustion which may lead to heat stroke basically because we can't perspire due to the fact that our body temps reach > 105 F. This can effect all your organs. The combination of high heat and humidity effects plants transpiration process = basically it can't take up nutrients through it's roots and can't sweat or perspire like it normally does through it's leaves. The plant becomes stressed out and is susceptible to blackspot, yellowing/brown leaves which eventually defoliate. Mature leaves will also drop. I know this isn't a very scientific way of describing transpiration but I think you get the idea. Once you have black spot all you can do is try and control it. Ideally, it is best to apply a fungicide to act as a preventative so it doesn't start in the first place. It rained for days and days here and there was no opportunity to apply a fungicide without it being washed off followed by more rainfall. When it finally did stop raining, we had high temps in the 90's along with 90% humidity - and this weather pattern continued. The first Spring flush was marvelous. The second flush was almost nonexistent - blackspot, powdery mildew, spider mites, plants defoliated, fewer & smaller flowers, little new growth, normally orange colored flowers appeared red. This past Sat. Sun. & Monday, we had 3 days of relief with dry low humidity & temps. Tomorrow we will be back to high humidity with no end in site for at least the next week. Praying the temps don't go into the 90's. It is my understanding that there are 5 different strains of fungus in the US. The fungicide I am using is effective here. I apply OxiDate every 2 weeks as a spray. If there is a breakout of black spot and/or powdery mildew, it is applied every 5 - 7 days. http://www.biosafesystems.com/... I apply this to the leaves, the stems and to the soil under the rose canopy and adjacent plants. When pruning, the pruners are dipped into a solution of 10% bleach to water or alcohol to water mixture with each cut. After pruning OxiDate is applied. I prune in the Spring when the forsythia begins to bloom. I would use the OxiDate on the wisteria. Water - about 7 gals. per rose per week using slow drip method. Mulch under the roses but not touching canes. Spider Mites - blast with water as described by jerijen in previous post - thank you Thrips - Blue sticky Traps - https://www.planetnatural.com/... I hang these about 15 feet away from my roses. The idea is to lure the thrips away from the roses and towards the traps. I place them in the early Spring before the irises bloom. For Japanese Beetles you might want to consider applying Milky Spore or nematodes "specifically" for Japanese Beetles. Slugs - lids from jars filled with beer. They don't seem to show a preference for the type of ale. Presently, I am trying out Actinovate SP - https://www.amleo.com/actinova... Read the reviews. I think it's a good idea to alternate products from one year to the next. Please feel free to contact me. Observe, observe, observe We are fortunate to "see" & appreciate nature in ways others are blind. |
MargieNY Aug 15, 2019 9:22 AM CST |
Part 2: Spraying gives me the opportunity to observe/reevaluate each individual rose. I look for problems like brown or yellowing canes, canker, insects that bore holes into canes, RRD, etc. If you notice canker which is apparently caused by bacteria/ fungus, prune the cane down till the pith (center part of cane) is white in color and no longer a tannish color even if it means cutting to ground level. I follow it up with OxiDate. When I see a plant stressed out due to weather conditions or disease, I usually remove any blooms it is attempting to produce in an effort to redirect it's energy. Every few years, I remove one old, aging cane from rose bushes to help rejuvenate the bush. This stimulates the rose bush to produce nice new green canes to emerge. One advantage of roses grown in pots is you can move them into shady locations if necessary. When sited in the ground, something like a lawn chair can provide shade. Growing hybrid teas here is a challenge. I have found by siting them in a location where they receive morning sun allows them to dry up the morning dew, partial shade in the afternoon to avoid the hottest part of the day and than more full sun in the later afternoon has shown to be successful. Although I have gathered much of this information that I am sharing with you through trials and era, I would like to thank all members both past and present for your most helpful advice over the years. I found it valuable to map out my garden every couple of years to show which areas receive full sun, partial shade or full shade. Observe, observe, observe We are fortunate to "see" & appreciate nature in ways others are blind. |
hampartsum Aug 15, 2019 9:31 AM CST |
My congrats Margie for the above posts! ![]() ![]() ![]() ![]() Arturo |
SW Ohio River Valley (Zone 6b) vaporvac Aug 15, 2019 10:18 AM CST |
I wish I knew what the growth is beneath the soil. Great advice here. I would say if you're trying to grow New Dawn in a pot for any length of time, you might have issues. This is a large rose that requires a lot of space and deep soil. I notice my roses succomb to issues when I slack on something.... usually watering. We generally have so much rain I rely on it and forget to help them out. Once my pots dry it's difficult to really soak them without plunging them in a large bucket and letting them sit for a while. This is because my mix uses some peat. |
Staten Island, New York Leeann79 Sep 8, 2019 8:06 AM CST |
Thank you for a lot of advice, I believe I have all of the insects and fungus that exists in NYC! I chucked the Quicksilver (Lavender rose) because something was living inside the canes, so I left my New Dawn even though the leaves are unsightly it's still blooming a lot and the blooms are finally looking healthy, but some do appear to be much lighter in color, almost white. What would cause the change in color? Someone mentioned about me having the new dawn in a container? The container is bottomless, it's half in ground half out. I did that to have better control and it worked great for 4 seasons. Do you think this is becoming a problem now? Also I'm not sure what steps to take for winter preparation? Do I keep trimming and spraying? |
hampartsum Sep 8, 2019 3:36 PM CST |
@Leeann79.My New Dawn blooms differently according to the seasons. I also experience much lighter colours in midsummer while it does get darker as fall sets in. My ND will keep blooming all the way into late fall even after first frosts. The container is bottomless, it's half in ground half out. I did that to have better control and it worked great for 4 seasons.. I'm not sure about the advantages of doing so, but at one point imho, you either put it fully in the ground levelled with the rest or pile up soil as a raised plant. The second option may be of use if your soil is heavy clay. By having it raised you improve the drainage and aereation. Four years is enough time to have built a good root ball. Since ND is a climber, thus a fairly large bush, the container rim might eventually reduce spread of the upper feeder roots. In that case it would be better to get rid of the rim, pile soil around the bush mixed with manure/compost and place stones , or any other retaining materials so that the soil is kept in place., specially since you are prone to very heavy rainfall and snow that could easily wash it away. Arturo |
MargieNY Sep 8, 2019 5:52 PM CST |
I agree with Arturo - either plant it in the ground or you have to pile lots of soil high around the planter/canes followed by mulch. Here is a video that you can watch to get a better idea on how to perform this procedure. https://palatineroses.com/wint... I don't know if your New Dawn is an own root or if it is grafted but you do want to protect the grafted area in particular. The other thing you might want to consider doing is to wrap it with burlap. I did this with a rose by inserting 3 bamboo stakes into the ground around the rose to form a tee pee frame. I tied the 3 stakes at the very top with a twisty and than wrapped the burlap around the rose and stapled the raw edges closed. So, if you first piled the dirt up high, add the mulch, encased the rose with the burlap and added the rocks to the outside perimeter, I think that would work. Keep in mind you don't want to "Winterize Roses" until we are very close to our First Fall Frost. Observe, observe, observe We are fortunate to "see" & appreciate nature in ways others are blind. |
Staten Island, New York Leeann79 Sep 14, 2019 7:47 AM CST |
Thank you for more great info, and MargieNY I will watch the video. All my plants are either in pots or raised beds because I have very compact clay soil mixed with gravel that the previous owners just kept piling on the dirt. I also figured with roses to help with back spot and fungus problems clean up is easier. For winter I will pile dirt and mulch to protect the root ball from the frost. Maybe next season I will remove the rim and put a wider one to give it more room, I'm afraid of this years fungus and insect issues finding a comfy home for the winter now. I've been treating it at intervals weekly with a fungicide and before I pile on the dirt. I'm not sure if my original plant is grafted or not, I purchased it at Lowe's years ago, but this season I planted another one that I propagated last year from my original one, in replace for my Quicksilver that I removed. I want it to thrive but I don't have experience in growing and training a new dawn this young. Any advice for me? I don't want to lose control of training it but I know you're not supposed to prune it to young. So far it has lots of small delicate limbs everywhere with sporadic blooms, should I leave them or cut them back for the winter? Also wondering what kind of soil should I pile on the bases for both plants? |
hampartsum Sep 14, 2019 8:28 AM CST |
Also wondering what kind of soil should I pile on the bases for both plants? If your garden soil is mainly clayey, then for each plant, I would fill a bucket of that, plus one other of riversand and a third of manure(horse,cow dung) plus leaf compost, leaf mould,or any other organic substrate. Mix it well and pile it up around your bushes making sure that your graft union is kept below the surface. Then add a generous ammount of dry leaves as a mulch and place pieces of bark, sprinkle soil or stones to keep the leaves from blowing off with the wind. In spring, as you say remove, the rim of the container. Then all the winter mulch leaves can be forked under as well. Arturo |
MargieNY Sep 14, 2019 9:44 AM CST |
Leeann79 said: I'm not sure if my original plant is grafted or not, I purchased it at Lowe's years ago, but this season I planted another one that I propagated last year from my original one, in replace for my Quicksilver that I removed. I want it to thrive but I don't have experience in growing and training a new dawn this young. In most cases you don't want to prune newly planted climbers for the first 2-3 years - you want nice long canes to eventually position in a horizontal position. The reason as to why you want to bend the canes horizontally: Because there is a hormone that flows from the tip of the shoot that signals the buds below it to remain dormant. When that flow is interrupted by tying the canes into a horizontal position, the lateral buds do not receive the signal, and they break into growth and bloom! If you allow a climber to grow straight up, you will only produce blooms at the top. So, you have to bend them into a horizontal position - arch them or wrap them around an obelisk. You can only bend the canes in the Spring and summer, when the canes are green and pliable. In the Fall, the canes are too stiff. In the Fall, you want to tie the canes securely so they don't whip around in windy conditions. Velcro tape is great to use. Pruning is usually done when the roses are dormant. Observe, observe, observe We are fortunate to "see" & appreciate nature in ways others are blind. |
SW Ohio River Valley (Zone 6b) vaporvac Sep 14, 2019 11:06 AM CST |
I have many New Dawn and the canes you are seeing now are baby canes. When the rose has a comfortable root mass it will send out large and long canes that will further send out long laterals. This is a huge vigorous rose that can grow a massive root system. I've moved mine around multiple times and can attest to their deep tap roots and feeders. However, it's a very adaptable rose. A couple I have in gravelly soil do just as well as those in perfect loam if given enough water. It will bloomsome with almost total neglect, but will reward you with near constant bloom and growth with just a little care such as amendments and dead-heading. let us know what you do. ![]() |
Staten Island, New York Leeann79 Sep 15, 2019 6:05 AM CST |
Thanks for your help, so I will let my baby New Dawn grow freely until it's time to close up the yard and then secure the canes for the winter. Hopefully next summer things go better :thank you everyone |
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