My lemon tree is about 7 years old and was growing beautifully, bearing many lemons and suddenly all the leaves started falling off, not dead yet but looks awful.
This article will help you pinpoint the cause of leaf drop in your Lemon Tree.
https://www.gardeningknowhow.com/edible/fruits/lemons/lemon-tree-leaf-drop.htm
Why are my lemons falling to the ground before they are ready? Many are still small and green/yellow. The leaves appear healthy.
This article will help you:
https://www.gardeningknowhow.com/edible/fruits/lemons/lemon-tree-fruit-drop.htm
How can I ripen the lemons on my dwarf tree that I have to move inside because of fall weather? I need to know what supplemental light would be good for this.
CFL lightbulbs along with a reflector light fixture are great supplemental lights for indoor fruiting or flowering plants. You can also surround them with mylar reflectors to maximize light reaching the plant. And keeping the plant near a window helps too.
Recently, I bought 2 lemon trees from Walmart. One is now blooming but the other has spotted leaves. They both have the same soil composition. It is Nov. 11, should the tree be blooming? What is wrong with the other one? It is listed as a patio tree. I live in Cantonment, Fl and the weather has been unseasonably warm (high 70's and low 80's). Could this cause the tree to bloom? Mickey
Some Citrus can bloom up to 4 times a year. Blooming can be triggered by temperatures and watering.
Spotted leaves can be do to insects or fungus problems.
You can treat the plants with Neem Oil. Neem Oil works as both an insecticide and fungicide and is safe for people and pets.
You could also return the plant that is showing leaf damage.
Here are several links for you with more information.
https://www.gardeningknowhow.com/edible/fruits/citrus/citrus-blooming-season.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/growing-lemon-trees-containers.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/how-to-grow-a-lemon-tree.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
Our 20 year old lemon tree appears to be dying. The leaves are dropping off and are yellowish, and some of the branches are dead. The fruit still seems ok. We have never had any problems with this tree before and we have not done anything different. Our ornamental grapevine is also looking not good, leaves yellowish and no healthy growth, which is unusual for this time of year. There is a little splitting of the lemon tree's bark near ground level, and one branch in particular. Its bark is cracking. Noticed some mealy bugs for the first time ever on lemon tree. Our concern is that our neighbour has several trees that appear dead or dying!!
Since both your lemon tree and grapevine may be affected, this could be a soil nutrient deficiency. Nitrogen, iron, potassium, or magnesium deficiency can cause yellow leaves and poor growth. You may want to have a soil test done.
http://www.aces.uiuc.edu/vista/html_pubs/hydro/symptoms.html
https://www.gardeningknowhow.com/plant-problems/environmental/leaf-chlorosis-and-iron.htm
Or, there could be a disease present. This article is about oranges, but most of the advice applies to lemons as well:
https://www.gardeningknowhow.com/edible/fruits/oranges/yellowing-orange-tree-leaves.htm
I have two lemon trees, both about the same, about 18" tall in containers. One is blooming and has very small lemons forming on it. The other is not doing anything. Could it be possible that I have a male and female tree, if there is such a thing? The one that is not blooming had bird poop caterpillars this summer and the other did not, even though they sat next to each other on my patio. They are supposed to be Meyer lemon trees, according to the nursery. Please let me know. Thank you, S Buckler bucklers1984@gmail.com
Each Meyer lemon tree is both male and female and is able to pollinate itself. The caterpillars are a more likely cause of the problem- perhaps they weakened the tree last summer. Hand removal can be very effective if they are only on one or two trees.
The tree might also be too young to flower. See this article:
https://www.gardeningknowhow.com/plant-problems/environmental/plant-not-blooming.htm
My lemon tree is getting attacked by some insect. Some kind of glossy film and also beginnings of black specks on the leaves. What can I do? Is there something I can purchase or a home remedy?
The symptoms you see are probably caused by sooty mold and by aphids or scale insects that promote sooty mold growth. See these articles for control options:
https://www.gardeningknowhow.com/plant-problems/disease/how-to-get-rid-of-sooty-mold.htm
https://www.gardeningknowhow.com/plant-problems/pests/insects/homemade-aphid-control.htm
https://www.gardeningknowhow.com/plant-problems/pests/insects/control-plant-scale.htm
http://ipm.ucanr.edu/PMG/PESTNOTES/pn74108.html