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Shasta Daisy-browning, die back

    Date Posted: Tue, Aug 17 - 8:52 pm

    Question

  • I have a large shasta daisy that I planted along my side yard years ago. About 3 years ago it started having "issues". It starts the spring with very green and abundant stems/leaves. And everything seems wonderful as the plant starts to bud....but then the flowers bloom already browning and die quickly. I am guessing it has some kind of wilt but not sure what to do. I also have dianthus in pots up my steps for the first time and it appeared that they also caught "the wilt" but they seem to be bouncing back. Not so for my Shasta daisies. Is there anything I can spray them with or can I transplant? It's such a gorgeous prolific plant.
  • Answer

  • Sorry to hear of your daisy troubles. I'm going to refer to a previous answer I gave about Rudbeckia 'Goldsturm'. The daisies are also one of the stalwarts of the garden but can run into various problems. Please see the rudbeckia answer below. I didn't spell it out in the answer below but good drainage and air circulation are essential for plant growth and prevention of fungal diseases. And again, if your plants continue to succumb, selection of a new plant for your particular environment may be a good solution. Good luck, let us know your progress! "Rudbeckias are usually pretty sturdy plants but they do succumb to some fungal issues. Sometimes the problem could be attributed to too much water, so that's a simple fix. Or, you may be dealing with septoria leaf spot or a similar fungus. Rain and humidity contribute to the problem. You can start with some cultural practices. Remove all affected leaves and put them in the trash. The fungus overwinters in infected plant debris so you want to clean up the area around the plants to make them less inviting to the fungus. You may also try moving the plants to a spot with new soil and seeing if the plants improve over time. Additionally, do not water from overhead. Try a soaker hose so that the foliage does not get wet. You could also try a baking soda solution spray but that's usually better at prevention. A neem oil solution may be effective. You may decide to simply remove them from the garden and substitute another perennial that's less susceptible. There are many choices. A lot of gardening is just adapting to your circumstances and trying new plants that may be better suited to your patch of ground. Best of luck with your garden! "

Rudbeckia-leaves blackened

    Date Posted: Tue, Aug 17 - 8:51 pm

    Question

  • I’m having a problem with my Rudbeckia Goldstrum. The leaves are blackening and the plants dry out and die. I took pictures but can’t figure out how to attach them to this message. So far the problem is only with the Rudbeckia.
  • Answer

  • Hello there, Rudbeckias are usually pretty sturdy plants but they do succumb to some fungal issues. Sometimes the problem could be attributed to too much water, so that's a simple fix. Or, you may be dealing with septoria leaf spot or a similar fungus. Rain and humidity contribute to the problem. You can start with some cultural practices. Remove all affected leaves and put them in the trash. The fungus overwinters in infected plant debris so you want to clean up the area around the plants to make them less inviting to the fungus. You may also try moving the plants to a spot with new soil and seeing if the plants improve over time. Additionally, do not water from overhead. Try a soaker hose so that the foliage does not get wet. You could also try a baking soda solution spray but that's usually better at prevention. A neem oil solution may be effective. You may decide to simply remove them from the garden and substitute another perennial that's less susceptible. There are many choices. A lot of gardening is just adapting to your circumstances and trying new plants that may be better suited to your patch of ground. Best of luck with your garden!

Mint-powdery mildew

    Date Posted: Tue, Aug 17 - 8:48 pm

    Question

  • I am growing organic mint in a pot. Noticed that there is powdery white stuff on the leaves. What is that and how can I treat it naturally? Is it safe to eat / use the mint leaves if it has this white powdery stuff on it? Thanks Vilma
  • Answer

  • The powdery white stuff you see sounds like the fungus powdery mildew. This is a very common problem with many plants but it is not difficult to correct in this type of situation. If you can, first, isolate the plant and remove affected leaves. There are many solutions. I'll list 3 here and you can see which one suits you and try another if the first choice doesn't do the trick. 1.Try using this combination-1 gallon water, 1/2 teaspoon non-detergent soap, 1 tablespoon baking soda. Pour this solution into a clean spray bottle and liberally apply this to the plant. The soap will help the diluted baking soap stick to the mint leaves and stems. It's best to water the plant well before using the solution and don't apply while the plant is in hot sun, early morning is best. You can repeat this every 7 days and after a rain. Some people feel this works best as a preventative rather than a control. So if you find that you're having the same issue with powdery mildew year after year, apply this solution at the beginning of the season. 2. Another solution is a mixture of 3 tbsp. of neem oil to one gallon of water, sprayed onto affected plants every 7-14 days. Again, don't spray while the plant is in hot sun to avoid burning. 3. And yet another possibility is using milk. I have never tried this but I understand you can get some good results. Try a mixture of 4 parts milk to six parts water and spray bi-weekly. Apply in early morning. In all cases, try any solution on a test leaf first to see how the plant responds. And no, I wouldn't eat the leaves that are covered in powdery mildew but once the plant shows no signs of the fungus, feel free to use the plant in whatever dish you like. Good luck and let us know which solution was successful for you.