Meyer lemon tree dropping leaves - Ask Extension
My (indoor) Meyer lemon tree has been rapidly dropping leaves. At first I thought it was because I was overwatering it (the leaves would pale and shri...
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Meyer lemon tree dropping leaves #854908
Asked November 07, 2023, 7:42 PM EST
My (indoor) Meyer lemon tree has been rapidly dropping leaves. At first I thought it was because I was overwatering it (the leaves would pale and shrivel up) and so I stopped watering it for a couple months and then I think it dropped less, but now it is losing leaves rapidly again, (now they will have spots occasionally before they drop)and so I watered it because the soil was very dry. But it is still dropping leaves, and I’m afraid it won’t have any left. Now its losing about ten a day, maybe a little less. A little before this problem started, I treated the tree with neem oil for spider mites. Another thing I noticed was that the leaves that were falling were all on the side of the tree with less sun.
Montgomery County Maryland
Expert Response
Citrus are sensitive to having their roots stay too damp, so over-watering is a fair guess as to what was stressing it earlier. Not watering at all for weeks at a time is drastic, though, and likely contributed more stress on the roots, which can lead to more leaf drop, even if delayed by a few days/weeks after watering resumed. Citrus want to dry a bit between waterings, but not get completely dry, nor stay consistently wet. They do best in very bright light while indoors, with cool temperatures and moderate to high humidity. Our Growing Dwarf Citrus page provides a bit more info.
Neem oil (which is one type of horticultural oil) can help treat spider mites, but repeat applications are needed for several rounds of treatment until the mites are gone or no longer causing damage. Depending on how it was applied (say, if it was not diluted properly), its application might have caused leaf damage and then shedding. Damage from the mites could also be contributing to general plant stress that leads to leaf shedding. As you can see, there are lots of overlapping potential causes for plant stress, which in turn can result in leaf drop or discoloration.
For now, just feel the soil when determining if watering is needed, waiting for it to get somewhat dry to the touch at least a couple inches deep before watering. The pot should have at least one unobstructed drainage hole in the bottom, and if the pot sits on a saucer to drain, empty that saucer promptly after watering so the pot doesn't sit in water, which can keep the bottom roots too wet. Don't fertilize until spring at this point, and if it's been a year or more since the plant was last repotted, consider repotting either this winter or in spring so you can refresh the soil for the benefit of root health. Repotting doesn't necessarily mean the plant needs a larger pot unless the roots have really crowded the pot, but it does at least involve that fresh potting mix replacing the old mix, which helps to keep the soil free-draining.
Given the relatively low light levels indoors from windows in fall and winter, it's unlikely the citrus will put out much new growth between now and spring. If it stabilizes and isn't too stressed, it might replace a few of the fallen leaves with new growth, but we would not expect it to fully leaf-out again so soon. If the tree can spend next summer outside (in shade at first, gradually moving into more sun), that will greatly help it recover plus store enough energy to use during winter when its resources are limited. The fact that most of the falling leaves shed from the side of the tree away from the light source could just be coincidence, or perhaps they are getting too little light for the plant to bother keeping.
If this tree spent some time outside this summer before being moved in for the fall, that transition can also result in some leaf drop, and in that case shedding is perfectly normal. This shedding phase can also happen with plants recently purchased that were being grown outside or in a greenhouse, since in-home conditions are quite different and the plant needs time to adjust.
Miri
Neem oil (which is one type of horticultural oil) can help treat spider mites, but repeat applications are needed for several rounds of treatment until the mites are gone or no longer causing damage. Depending on how it was applied (say, if it was not diluted properly), its application might have caused leaf damage and then shedding. Damage from the mites could also be contributing to general plant stress that leads to leaf shedding. As you can see, there are lots of overlapping potential causes for plant stress, which in turn can result in leaf drop or discoloration.
For now, just feel the soil when determining if watering is needed, waiting for it to get somewhat dry to the touch at least a couple inches deep before watering. The pot should have at least one unobstructed drainage hole in the bottom, and if the pot sits on a saucer to drain, empty that saucer promptly after watering so the pot doesn't sit in water, which can keep the bottom roots too wet. Don't fertilize until spring at this point, and if it's been a year or more since the plant was last repotted, consider repotting either this winter or in spring so you can refresh the soil for the benefit of root health. Repotting doesn't necessarily mean the plant needs a larger pot unless the roots have really crowded the pot, but it does at least involve that fresh potting mix replacing the old mix, which helps to keep the soil free-draining.
Given the relatively low light levels indoors from windows in fall and winter, it's unlikely the citrus will put out much new growth between now and spring. If it stabilizes and isn't too stressed, it might replace a few of the fallen leaves with new growth, but we would not expect it to fully leaf-out again so soon. If the tree can spend next summer outside (in shade at first, gradually moving into more sun), that will greatly help it recover plus store enough energy to use during winter when its resources are limited. The fact that most of the falling leaves shed from the side of the tree away from the light source could just be coincidence, or perhaps they are getting too little light for the plant to bother keeping.
If this tree spent some time outside this summer before being moved in for the fall, that transition can also result in some leaf drop, and in that case shedding is perfectly normal. This shedding phase can also happen with plants recently purchased that were being grown outside or in a greenhouse, since in-home conditions are quite different and the plant needs time to adjust.
Miri
