Answer:rhododendrons, but it is an evergreen meaning the leaves should stay on all winter. In shadier situations, the plant may eventually lose some lower leaves simply due to lack of light, this would be a normal occurrence during the adjustment process. If the plant was very dense and grown in full sun when purchased and is now in a shady spot, this could be a possible explanation. They may also naturally lose some leaves at the base as they grow. Another common explanation would be overwatering, in that the soil should be kept evenly moist but never soggy. To tell if and when you need to water, dig down a bit and check the soil with your finger. Make sure it is not planted in a low spot or extra wet location in rainy times as well. A layer of several inches of organic mulch such as shredded bark is also a good idea to help keep the soil more evenly moist. Too deep a layer however can cause the roots to suffer a lack of air and consequently grow up into the mulch making the plant more susceptible to drought and cold. Finally, it is always a good idea to pick up and remove any fallen leaves, just in case there is an insect or disease problem at work. If the defoliation is extensive, I would suggest taking a sample as well as some photos of the overall plant for consultation with professionally trained nursery staff, preferable someone with a depth of experience in growing this type of plant. Good luck with your PJM!
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