Fungus in Garden? - Ask Extension
Hello,
I recently renovated my front flowerbeds, starting with digging up some spiderwort in March/April and transplanting it to another flowerbed ...
Knowledgebase
Fungus in Garden? #832836
Asked May 30, 2023, 8:49 PM EDT
Hello,
I recently renovated my front flowerbeds, starting with digging up some spiderwort in March/April and transplanting it to another flowerbed with more shade as they always got crispy and died in the spot they had been placed. I also moved a few catmint by a few inches to get them off of the wall of the house. I also moved around some coneflowers and stella d'oros for slightly better placement in the garden. Then, I purchased a lot of new bushes and plants, a little at a time, starting with an azalea, some fire and ice plants and one other spring bloomer. They all have been fine so far, although I may now be starting to see signs of potential issues. Then, I purchased three candy corn spirea and two clematis at the end of April/early May. Within a week of planting the spirea, I noticed spots on the leaves with many eventually turning completely brown and crispy and falling off. I also only planted one of the clematis and one vine had gone completely black and dead with the other vine looking rough and some dead at the top. I cut off the dead of the clematis and it seems to be doing better now. The spots are kind of rust/reddish colored on the spirea and the spots on the clematis were black. One of the three spirea plants has been hit the hardest, with it being the one from the nursery that I remember thinking didn't look as good. Even after seeing that happening, I still continued to purchase and plant new plants (little lime hydrangeas--purchased online prior to realizing the spots on the spirea), midnight sun weigela, and ... . I planted the hydrangeas in a separate bed from the spirea probably a week after planting the spirea, but in the same bed as the transplanted spiderwort, which all now are having leaves turning yellow and falling off. The spiderwort has very clear black spots and the hydrangea also seems to have some black spots too, although not as prominent as the spiderwort. This also seems to be the case with the coneflowers and stella d'oros. The weigela are harder to tell spots as the leaves are red in color, but many are turning brown and dying and ... are getting kind of white in color on the leaves and then the leaves falling off. Several rose bushes also seem to have a more white-colored spotting and the leaves getting a lot of holes in them. Several pre-established salvia also have had holes in the leaves too.
I've tried buying a bottle of daconil fungicide and spraying the plants, but the spray came out in a stream so didn't cover the plants too well. Then I purchased some neem oil but wasn't sure if it was as effective as less-natural products. I then purchased a daconil funguicide concentrate and sprayed everything once (waiting about a week to apply after spraying the neem oil). After that application, the spirea leaves looked worse than when I started. I waited six days before doing another neem oil treatment (which was today 5/30) and again, the spirea leaves looked worse than when I started. I have also tried removing as many really bad leaves as possible on the weigelas, hydrangeas, and, with one of the spireas almost having no leaves now, which can't be good. I've also been trying to water the plants as close to the ground as possible so as not to splash the leaves and I've tried cleaning up all of the dead leaves from around the plants. Maybe the spirea is too close to the catmint and not getting enough air, which I'm trying to trim back the catmint around the spirea. I'm at a loss of what to do and I have spent so much time and energy and money on everything and I feel like all of the plants are going to die. Do you have any advice?
Thanks a bunch!
Warren County Ohio
Expert Response
Wow. Your description of all the work you have done in your garden sounds exhausting! With all of those different plants, you probably have quite a variety of "ideal conditions"--pH, drainage, sun/shade, watering requirements, etc. Chances are, many of them are a bit stressed from moving (even into better positions), shipping to the nurseries they came from, and the weather fluctuations in general.
Stress will, of course, make plants susceptible to almost any disease present. Since it sounds as if they came from different sources, any one of them may have brought in a pest or fungus. Add that issue to soil nutrient deficiencies or excesses (every plant has different "ideal" conditions), and you have a perfect storm.
One nice thing with the variety that you have is that what one plant may suffer from may not affect a different plant. Even fungi of various types will not necessarily grow on the neighboring plant. So, even if some plants are diseased, chances are good you will not lose everything unless it is an overwhelming habitat issue.
Neem oil is a pesticide, but the degree of efficacy depends a lot on the life stage of the insect you are trying to control and the weather conditions. If you don't know specifically what you are trying to kill, it is hard to say that it is or isn't working. It is important to mix it strictly according to label directions to avoid plant damage--some products have surfactants and detergents in them that could cause plant damage. Many things can cause holes in plant leaves and many are past the controllable stage when the damage is noticed. (See third link below about rose leaf damage).
The daconil fungicide may have similar issues. While it is effective against a variety of fungi, according to the label different plants are ideally treated at different times (eg "spring bud break, early propagation, or warm moist conditions"). It also cautions against use in hot sunny weather (which we have had a lot of).
So, I guess a summary of the above information is that you have quite a variety of different plants, likely with different specific issues, and your broad spectrum products may not be as effective as you would hope. One approach might be to stop using the chemicals (even organic ones can have side effects on plants), provide good husbandry as far as watering and fertilizing (which it sounds as if you are trying to do), and wait and see if the plants throw off their stress and survive. Likely not all of them will, no matter what you do. It is always a good idea to remove diseased or dying leaves and remove them. If you have a source of biologically active compost, work some of it in around the base of the plants. It can't hurt.
If you want to approach it more scientifically, read through the post below about diagnosing plant diseases. You may find that there is something else (drainage? pH?) affecting the plants. Have you had a soil test done? Your county extension office can help you with that. The C. Wayne Ellett Diagnostic lab will take samples and provide you with specific recommendations based on analysis of the plant tissue. Are you actually seeing insects? If so, you can send me a picture and I can try to ID them and see if they may be damaging your plants.
Questions about diagnosing plant disease to help you formulate a tentative diagnosis:
20 Questions on Plant Diagnosis | Ohioline (osu.edu)
C. Wayne Ellett Plant Diagnostic lab (takes sample from residential gardeners):
Home | PPDC (osu.edu)
https://marylandgrows.umd.edu/2019/05/29/whats-eating-my-rose-leaves/
If nothing else, you can get good information on how to make specific plants the happiest by doing an internet search for the plant name and adding a ".edu" after it. This will give you research-based information that can be relied on. You may find that some of the plants you would like to see next to each other for purposes of your color scheme or other decorating criteria (height, time of blood, etc) do not play well together or like the same soil. Some examples on fact sheets on hydrangeas and weigela are below.
Hydrangea | Home & Garden Information Center (clemson.edu)
Weigela florida (Old Fashioned Weiglea, Weigela) | North Carolina Extension Gardener Plant Toolbox (ncsu.edu)
Good luck; I hope I have helped a little. Wish there was an easier, straight forward answer!
Stress will, of course, make plants susceptible to almost any disease present. Since it sounds as if they came from different sources, any one of them may have brought in a pest or fungus. Add that issue to soil nutrient deficiencies or excesses (every plant has different "ideal" conditions), and you have a perfect storm.
One nice thing with the variety that you have is that what one plant may suffer from may not affect a different plant. Even fungi of various types will not necessarily grow on the neighboring plant. So, even if some plants are diseased, chances are good you will not lose everything unless it is an overwhelming habitat issue.
Neem oil is a pesticide, but the degree of efficacy depends a lot on the life stage of the insect you are trying to control and the weather conditions. If you don't know specifically what you are trying to kill, it is hard to say that it is or isn't working. It is important to mix it strictly according to label directions to avoid plant damage--some products have surfactants and detergents in them that could cause plant damage. Many things can cause holes in plant leaves and many are past the controllable stage when the damage is noticed. (See third link below about rose leaf damage).
The daconil fungicide may have similar issues. While it is effective against a variety of fungi, according to the label different plants are ideally treated at different times (eg "spring bud break, early propagation, or warm moist conditions"). It also cautions against use in hot sunny weather (which we have had a lot of).
So, I guess a summary of the above information is that you have quite a variety of different plants, likely with different specific issues, and your broad spectrum products may not be as effective as you would hope. One approach might be to stop using the chemicals (even organic ones can have side effects on plants), provide good husbandry as far as watering and fertilizing (which it sounds as if you are trying to do), and wait and see if the plants throw off their stress and survive. Likely not all of them will, no matter what you do. It is always a good idea to remove diseased or dying leaves and remove them. If you have a source of biologically active compost, work some of it in around the base of the plants. It can't hurt.
If you want to approach it more scientifically, read through the post below about diagnosing plant diseases. You may find that there is something else (drainage? pH?) affecting the plants. Have you had a soil test done? Your county extension office can help you with that. The C. Wayne Ellett Diagnostic lab will take samples and provide you with specific recommendations based on analysis of the plant tissue. Are you actually seeing insects? If so, you can send me a picture and I can try to ID them and see if they may be damaging your plants.
Questions about diagnosing plant disease to help you formulate a tentative diagnosis:
20 Questions on Plant Diagnosis | Ohioline (osu.edu)
C. Wayne Ellett Plant Diagnostic lab (takes sample from residential gardeners):
Home | PPDC (osu.edu)
https://marylandgrows.umd.edu/2019/05/29/whats-eating-my-rose-leaves/
If nothing else, you can get good information on how to make specific plants the happiest by doing an internet search for the plant name and adding a ".edu" after it. This will give you research-based information that can be relied on. You may find that some of the plants you would like to see next to each other for purposes of your color scheme or other decorating criteria (height, time of blood, etc) do not play well together or like the same soil. Some examples on fact sheets on hydrangeas and weigela are below.
Hydrangea | Home & Garden Information Center (clemson.edu)
Weigela florida (Old Fashioned Weiglea, Weigela) | North Carolina Extension Gardener Plant Toolbox (ncsu.edu)
Good luck; I hope I have helped a little. Wish there was an easier, straight forward answer!
I want to thank Lynn for all of the advice and information! I look forward to reading through it more thoroughly and trying some suggestions out. I’ve never struggled so much with outdoor plants and so this has been a bit stressful when I’m not quite sure what to do. I will look into the soil testing too as I was wondering if that might be an issue as well. I appreciate the guidance, quick reply, and willingness to help further if I see any bugs on plants in helping to identify them!
Gina
Sent from my iPhone
Gina
Sent from my iPhone
On Jun 2, 2023, at 12:43 PM, Ask Extension <<personal data hidden>> wrote:
You're quite welcome. We are all learning something new every day...just when you think you have a plant figured out, Mother Nature changes the rules on you.
Good luck! It sounds like you have a good start on something special
Good luck! It sounds like you have a good start on something special
