I have purchased a nice strong kaffir lime tree in the summer, it was growing quite well, flowered and wanted to bear fruit. When autumn came, I moved it inside in a insulated shed where the room temperatue is between 15 and 19 °C. However it lost an alarming amount of leafs so despite the fact I knew it's because of the adaptions, I was afraid the place was too cold so I moved it in my living room near the biggest window for best light conditions. There temperatures are a few degrees higher, the back door is not far so sometimes a cold breeze can come through when you open it, but the plant kept losing leafs on a steady pace. In the beginning of January it lost its last one, and the branches began to color brown. I also have a normal lime tree next to it with the same conditions. A few weeks ago the first proper sunlight came up again after weeks of cloudy and rainy weather and I noticed odd bumps on the trunk and stems of both trees, turned out those were scale insects, which I removed on both trees. How they got there I do not know since I sprayed both plants thoroughly with water before putting them inside. Even after removing them, the browning branches became more brown and neither plants are drinking much because they're in winter mode, despite all directions not to prune I had no choice, the brown was reaching the main trunk so I had no choice but to cut off all dead parts. Both trees are now down to 2 branches each which are healthy but I fear they won't survive till spring. In an effort to try again I am germinating kaffir lime seeds so I can try again and do better next time, but first I need to know exactly what i am doing wrong. Much googling resulted in conflicting information, so I am not happy of the misinformation floating around. Some say to keep lime trees warm and moist, others to keep it a bit colder and dry (during winter I mean) The lime trees I kept warm and moist (not wet, I watered once every week and just a bit, the lop layer of the soil was very dry and I use a moisture meter , however the deeper levels of the soil was moist enough ) I also have a smaller kaffir lime (I think its a dwarf varient ) which I kept in that colder shed, and watered only once a month, and that one too lost the older leafs but still has his newer ones and has no brown branches at all. So i am wondering, which of all the information is the correct one, how can I safely hibernate those kaffir lime trees without losing all its leafs Do I have to keep spraying water over the foilage during the entire winter period or not?
Welcome to the forum. It's useful to know that citrus roots become dormant at 13C and slows significantly as the temperature drops to that level. Your problem may be related to that. As temperatures approach the lower end of the range in the shed the roots will not be able to transport the moisture necessary to cool the leaves in their photosynthetic activity and the tree drops its leaves as a result. Trees can be kept dormant and over-wintered in a cool environment in which there is no light. They will also require very little moisture because of reduced activity. Alternatively, the trees can be kept in light as long as the roots are kept warm. This can be done by wrapping a few turns of a strand of small incandescent lights around the container. The spritzing of water will do little to raise the overall humidity level as its effect is transient. I wouldn't bother. Take advantage of the current lack of foliage to deal with the scale. Treat with insecticidal soap as indicated on the product label. All adult scale must be removed physically by hand prior to its application as the soap is ineffective against them. The spray must be repeated a number of times with 7-10 days in between.
My guess is that the combination of changing conditions and scale caused the leaf loss. Citrus tend to do this readily when certain imbalances occur. To encourage new growth I would suggest keeping them warm, the air humid, ensure plenty of light, and giving them a liquid fertilizer that is high in nitrogen and micronutrients. Something like miracle grow should be ok. Note that spraying with water only moistens things very briefly. You may want to consider a humidifier. Notice that warm and moist or cool and dry are not contradictory. Citrus are all about balance. When they sense an imbalance they will readily drop their leaves. Warmth tends to cause an increase in evaporation, so they need more moisture. When things are cool they need less. Citrus can do well under both conditions. However, warm and dry causes an imbalance. Also notice that "dry" can also refer to dry air. If the citrus are in a warm location and the air is very dry, even if the soil is wet, they will be out of balance.
Thank you for the clarification and feedback. So from what I can conclude the one in my living room requires the air to be more moist, which I was afraid of but didn't think it'd give this much impact, unfortunately I was wrong. How can I increase the humidity of the air without purchasing yet another device ? I would think putting a container of water on the heating would not make much difference because it is not nearby plus the room is too big for that. Would putting a container of water next to the pot help ? Or is there something else? Thanks in advance!
