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Yellow Spots on Rhododendron Leaves
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Date Posted: Wed, Aug 18 - 2:01 pm
- My large rhododendrons have some yellow specked leaves. Been watering every other day. What are you suggestions
- Hello! Thanks for your question. Given our recent warm and humid weather conditions, the problem you are having with your rhododendron is certainly not uncommon. I suspect your plant has a fungal condition called leaf septoria (yellow leaf spot). It sounds as though the condition on your plants is not widespread at this point and there are a few steps you should take to rid your plants of this fungus. First, remove the affected leaves to get rid of as many fungal spores as possible. Secondly, take away any fallen leaves from under the plant and keep the area clean. Discard all removed leaves in the trash (not compost). Mulch the area under your rhododendrons; this helps prevent spores from spreading. It will also help retain/absorb the water when you are watering the plants, and reduce splash upwards. And when you water, it’s best to use a soaker hose at the base of your plants, versus overhead watering. Watering overhead and watering in the evening can increase fungal disease development on these plants. You can also apply a simple, all natural spray solution consisting of the following: one quart of water in spray bottle with 1 teaspoon of baking soda; add 1/2 teaspoon of canola oil and a few drops of dish soap; shake the solution well and spray on the plants. Good luck with this - improved weather conditions in the coming weeks hopefully will help as well! Let us know if you have further questions. Thanks! And of course keep a close eye on your other grow bags with your other vegetables for any similar signs. Good luck with your garden, and wishing you a strong yield!
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Watering roses
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Date Posted: Wed, Aug 18 - 1:48 pm
- Hi i have a row of drift roses on the front on my yard, they are in full sun. I had been watering them every other day with the lawn but noticed that a few bushes had yellowing leaves which then turned brown and crispy. I am assuming that is a sign of being overwatered? Any suggestions on how to make the flowers last so they don’t turn brown so quickly in the heat? Thanks!
- Hello there, My first instinct is that you are, in fact, over watering your roses. How long have the roses been planted? If it's been a few years then watering once or twice a week should be sufficient. Is the soil well draining? Roses don't want to sit in consistently wet soil. Are you able to gauge how much water, in inches, your roses are receiving. one to 2 inches of water (rain+water combined) should keep them healthy. I believe that's about 4-5 gallons of water a week. Also, I don't think the heat is causing the roses to brown but the effects of over watering are. Back off on the watering a bit. Try to avoid the foliage and water the soil around the plants and see that they get soaked rather than sprinkled. I suspect that less water weekly (avoiding the foliage whenever possible) and a couple of good soaks a week will make you and your roses happier. Good luck!
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Yellowing Aster
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Date Posted: Wed, Aug 18 - 1:46 pm
- Hi we have a row of fall aster and notice that this year and last as the rest of the plant grows large and bushy the base starts to get yellow and then dries. the plant seems to be getting enough water. Is this normal?
- Good morning, and thank you for your question! My first thought is that you may have a watering issue. I’m assuming your aster plants otherwise have normal growth, are not stunted, and bloom well. Asters do prefer well-draining soil and like to keep well watered. However, they do not like overhead watering or sprinkling. Doing so can result in development of a fungal disease. Watering should be done at the base of the plant where fungus would first develop. It also helps to use a good organic mulch around your aster plants to help retain moisture and prevent splash to the lower leaves which can cause the yellowing. As a side note, be on the lookout for leafhoppers on your aster. They can spread bacterial disease (phytoplasma), which is a more serious problem to deal with, but with this you would likely notice other symptoms such as stunted growth and deformed flowers as well. If those symptoms develop, the plants would need to be removed as there is no cure. It does not sound like you are experiencing these specific problems with your aster, and proper watering and mulching would be the best first steps to implement. Good luck with this, and let us know if further symptoms develop.
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Raised beds - yellowing leaves
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Date Posted: Tue, Aug 17 - 8:41 pm
- I created new raised beds and filled them with Miracle Grow Raised Bed soil combined with mushroom compost. All of my plants have yellow leaves. The soil should be provided the necessary nutrients, and I was wondering if the weather might be part of it? Can you give me an idea of what I should do? Thank you
- Hello - interesting question. The first thing that comes to mind is your soil. It sounds like you have created a very rich soil for your new plants. Typically, yellowing leaves can indicate a nutrient deficiency, and/or the soil is too wet. As you know, mushroom compost does a good job of soaking up a lot of water and helps keep soil moist. It is also nutrient-rich, and contains a high degree of soluble salts. I’m wondering if your ratio of mushroom compost to soil is too high. The mushroom compost should make up about 1/4 of the total volume of the soil. If your soil is too concentrated and the plants are seedlings or are very young, this may result in your plants dying. The soil may actually be too rich for them. Also make sure your soil is not staying too wet. It should be allowed to dry before adding water. Good luck, and let us know if we can help further!