I live in Canada, and I brought my lemon tree inside a few weeks ago for the winter. I keep it under a grow light for 8 hours a day and water deeply every one to two weeks. Ever since I brought in indoors, it's been struggling. The leaves (it starts in the veins) turn yellow and then they fall off. It's lost a lot of leaves already and I'm trying to prevent more loss. It has a few small lemons that grew over the summer. They're still quite small so I'm wondering if it's normal for them to grow so slowly? It had some fall flowers bloom, but they dried out pretty quickly and didn't become anything. What's going on with my tree? I don't think light or watering is an issue. I fertilize frequently but I'm not sure if I'm putting enough in each time. I alternate between the Miracle Gro Shake 'n Feed (10-5-15) and Miracle Gro all purpose plant food (24-8-16). What should I do?
Welcome to the Forums. I don't know what the problem is but I suggest considering 'yellow vein chlorosis' as a possibility even though I can't see it happening in such a short time. Is the (bare) tile floor cold? What is the temperature in the room? Does the container have drainage holes? I suggest you remove all the fruit, stop fertilizing the tree, and reduce watering to a minimum as the tree has lost most of its leaves. By the way, I suggest you use the 24-8-16 exclusively moving forward as its formulation is more suited to citrus. References: Citrus Problems in the Home Landscape A Guide to Citrus Nutritional Deficiency and Toxicity Identification
I don’t actually keep it on the floor. It’s usually on a stand near a southwest facing window. The temp is usually around 21-23. There’s one single drainage hole in the center. What if the tree loses the rest of the leaves? Is it just gonna be dormant now until next spring? I was hoping I could keep it actively growing all year but I guess that’s not the case.
Check the amount of moisture in the soil. Perhaps there's too much, but then leaves usually droop in case of root rot . Citrus trees are known to drop leaves when moved indoors for the winter but the leaves that are shed remain green. Do you have a cool, dark location in which the tree can be overwintered, with temperatures below 13C?
Last year when I moved it inside, it lost leaves but the leaves were green. Once I bought the grow light for it, new leaves started growing quickly. It’s not responding to the grow light right now. I have a cold cellar in the basement that’s dark and cool
Then it's an option to overwinter the tree there. Citrus roots cease to function in temperatures below 13C; therefore it's important that the tree be kept in the dark while there to inhibit photosynthetic activity. Under these conditions there'll be little need to water the medium. The tree can be taken outside again come spring where it will hopefully recover. Still, it's somewhat risky since the cause of the problem is unknown and the tree may continue to decline even in dormancy. Remember to not fertilize until new growth develops and then only at half-strength to start.
My only occasion, when my citruses started to change their leaves to yellow, was caused by root bound situation in containers. After up potting my citruses improved soon.
