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Rhododendron Questions
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Date Posted: Thu, May 08 - 11:14 pm
- I have an established rhododendron and a couple of questions 1. Some leaves tern yellow and die and fall off 2. Others show yellowing but remain 3. New shoots form at the base but die never to mature 4 is there any way to encourage new growth on the old branches
- Thanks for reaching out with your rhododendron questions! You’ve made some great observations, and your plant is definitely trying to tell you something. Here are a few possible explanations and tips based on what you described: Yellowing and Leaf Drop: Some yellowing and leaf drop is normal, especially for older inner leaves. However, widespread or early-season yellowing in Richmond can also point to stress from heat or underlying root issues, particularly since rhododendrons are naturally cool-climate, understory plants. Our warm springs and hot summers can make them more susceptible to systemic diseases or environmental stress. Persistent Yellow Leaves: This could be a sign of sun stress—rhododendrons prefer morning sun with dappled afternoon shade. Too much direct, hot afternoon sun can cause the kind of yellowing you're seeing. Poor drainage or soil that’s too alkaline can also cause nutrient uptake issues, leading to chlorosis (leaf yellowing). New Shoots Dying Back: When new shoots at the base fail to mature, it often points to root zone stress, such as poor drainage, fungal root diseases, or heat stress. Check that mulch isn't piled too high against the base and that the soil is staying moist but not soggy. Encouraging New Growth on Old Branches: Yes! Light pruning in early spring, just after flowering, can stimulate new growth. Avoid heavy pruning all at once; instead, gradually thin out leggy or unproductive branches over time. Make cuts just above a healthy bud or leaf whorl to encourage branching. Good luck with your rhododendron!
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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!