Leaf spot: the leaf spot fungus produces water-dispersed spores from fruiting bodies on the infections. By Teo Spengler Updated September 10, 2019 . The Royal Horticultural Society is the UK’s leading gardening charity. It is a list of products currently available to the home gardener. Too much shade can also cause fewer (or no) blooms. To fix it, I usually clean up around the plant and try to cut back a few branches to reduce overcrowding and improve the air circulation. I have used rhoddie fertilizer, iron supplements, and water. Hopefully it will come back. my rhodo is some years old and I live in N.ireland .I have noticed a lot of the leaves and some of the branches have turned black and buds are not prospering. I’m worried the plant is feeding too much energy into the new shoots. I would cut back the dead branches, make sure it is mulched well and that it is getting enough water. A second type of Rhododendron issue is brown spots on the leaves. If that’s the case, you can try to improve the drainage in the area. 1. Required fields are marked *. While this will provide quick relief to the plant, you will probably want to look into making your soil more acidic long term. I haven’t personally experienced that problem, but from your description it sounds like it could be Azalea Bark Scale. One potential Rhododendron problem is that the leaves are turning yellow. (You can find more about caring for your Rhododendrons HERE). They are spread by water and potentially infect buds through wounds made by the rhododendron leafhopper when it punctures the bud to lay its eggs (although some recent research has cast a doubt on this link between the pest and disease). The most common cause of not having any blooms is that the plant was pruned after flowering the previous year, or too much of the flower head was removed when deadheading. Unless you are trying to grow Rhododendrons that aren’t zoned for your area…then you might want to look for some other varieties that won’t be affected so much by the cold. Spores produced on spruce then reinfect rhododendrons. Should I prune it all back or is there a fertilizer to help it come back? It must be beautiful in the spring with all of the flowers! The bacteria causes an infectious disease in pants including rhododendron, mountain laurel, lilac, viburnum, and pieris. What is that? April 26, 2019 at 9:26 am . My rhoddie is about 15 years old. Chemicals: storing and disposing safely. A three-foot-tall rhododendron can cost more than $150 and take close to a decade to grow. In the autumn the leaves started to get brown, drying, but not on the hole branch. Again, there are a number of reasons why you don’t have any buds on your Rhododendrons. The MDA is asking anyone who bought a rhododendron plant in 2019 to carefully inspect the plant for any symptoms of infection and to report any concerns. In this case, they usually turn a light brown color and get a little mushy (for lack of a better term). It looks like it’s dying but it didn’t happen till after blossoming. Petal blight: the fungus causing petal blight produces wind-dispersed spores on old infected flowers which remain hanging on the plant from the previous season. Hi Terry…That’s a lot of Rhododendrons. Good luck with them! Are there other plants that have gotten bigger and may be interfering with the Rhododendron’s roots or causing it to get too much shade? Hi, I have a rhode whose leaves are yellow, droopy, and the bush basically looks like it is dying. They wont tolerate deep and dry shade and poor drainage/heavy clay soil. If the bark itself has actually turned black, that is probably not a good sign. This season it did produce leaves and the ones that are left are turning brown and falling off. They are small, the leaves look kind of wilted and yellowish. The … While most Rhododendrons will do fine in the shade, there are some varieties that like more sun. Perennial Ground Cover (21 Low-Growing Plants That Thrive in the Shade), Shade Container Plants: 10 of the Best Blue Annuals For Planters In The Shade, Daphne Plant: How To Grow A Daphne Shrub That Will Fill Your Garden With Fragrance, Mountain Laurel Care: How To Grow Beautiful Shade Loving Kalmia latifolia, Japanese Maples: 10 Things You May Be Surprised To Know About Growing Japanese Maples, Japanese Pieris (How To Grow and Care For Japanese Pieris Shrubs). A fertilizer to see if that ’ s were much colder, more snow, the blooms just! Spores that are stressed due to environmental conditions or injury a relaxing retreat! Causes the buds on the hole branch by another kind of fungus can! 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