Hi All, I have an indoor Calamondin tree in the Vancouver area. It is over 4 ft high and potted in a 2 foot circumference, 2 foot deep pot. I have it near a south facing window where it gets very little sunlight (maybe only 2 hours per day when it's clear in the winter) and I have a florescent (cheapo; fits in the 60w socket) grow light above it that is on 12-16 hours per day. I was living in a taller apartment building which got a lot more sun and was a lot warmer last winter. He thrived there. My current apartment doesn't seem to have it's own temperature control. It's never chilly in here, but I'd estimate it's usually in the mid-to-high teens. I think I water it properly (only when it's dry, less in the winter) and fertilize it every couple of months. When winter started, it began to lose it's lower leaves. For the most part, they would just fall off green, but recently I've noticed three or four with shriveled edges. I've placed my snake's old reptile heating pad under the pot, but that barely produces any heat; I doubt it would have a measurable effect on the average soil temperature. His name is Sir Herbert Claudius Balzac the Third, and I'd like to keep him alive through the winter. What is the best way I can improve his condition? Thanks, Trevor
Temperatures in the mid-teens is getting into the cooler side for citrus as their roots become inactive at 13C. This may partly explain the loss of leaves. The low-powered heat pad is insufficient for warming a large container. A better alternative is a string of incandescent Christmas lights wrapped around the container. The number of wraps can be adjusted according to the temperature desired. A soil thermometer would be useful in monitoring the temperature. A single fluorescent tube may not provide enough light for a tree this size. This may explain the loss of leaves in the lower portion of the tree where there will be little light. Also, light from such a distant source will have little if any benefit. Other than adding more bulbs you might try using reflective material to increase light levels - something like that seen in this post in illness on lemon? | UBC Botanical Garden Forums.
I have two about the same size one got really lanky when i put it outside and the other shrubbed up to very different personality plants. I do get more light than you but probably not enough, recently I changed all my bulbs in my house to full spectrum lights from Gardenworks a pack of 4 for about 20 bucks. They seem to be liking it one of the ones is putting out a bit of green growth and some new blooms. But for calamondins they are quite cold hearty only the trifoliata orange and the kumquat are heartier, I left mine outside till the middle of sept where it was about 15 degrees at night and they had no issues. Also check for spider mites, they run wild in Vancouver I was suffering leaf drop and it was actually spider mights so I treat them with neem oil every once in awhile.
There is another alternative for the OP if increasing the light is not practical. The tree could be over-wintered by keeping the temperature below 13C and keeping it completely in the dark. It will be dormant as long as these conditions are maintained.
Appreciate the advice guys. I ended up doing the following: 1) I bought a space heater. I spend a lot of my time near where the tree is and tend to turn it to the low- to mid- 20s when I'm home, and set it to turn on at 16 degrees at night. It rarely turns on since the cold snap ended. I think I've got temperature under control. 2) I upgraded the grow-light above to a 1700 lumen 26 watt one. I'm hoping that helps. 3) I also bought a tube style grow light to put on the wall slightly above, but to the side of him. 4) I re-potted him (I haven't done so in about three years) and pruned the roots a little. 5) A little light pruning throughout. 6) I remembered that I had a 24-8-16 fertilizer around that indicated it was for flowering plants. I had been using a 20-20-20 (rarely) before. I read that citruses prefer the higher nitrogen. True? a) I haven't actually used the fertilizer since the re-pot, but was planning on testing it in a week or two. I've attached a picture of his setup. Does anyone have any comments on these actions? Questions: 1) Several of his leaves had begun to turn brown and curl on the edges. I can't tell if they've gotten any worse, but I've attached two pictures. What is the likely cause? 2) How do I detect if he has spider mites? I inspected him closely during the re-potting and didn't see anything that looked alive. Are they big enough to see? 3) I've read that alkaline water is bad for citruses and that a solution is to put a very small amount of vinegar (spoonful per gallon) into the water with every watering. I don't know if my water is hard, but I live in an old building in East Vancouver. Would adding a touch of vinegar as a preventative measure be a good idea? In general, I think I've set him up pretty well and hope to watch him getting better over the next several weeks and months. But if anyone has any other comments, I'd appreciate it. I have a very novice level of knowledge on caring for plants.
how were the roots fresh or soggy?? good color or pretty boring? could be a drainage issue, how long does it take for water to filter through the soil? it kind of looks like a fertilizer burn to me but ya that or watering... I have found my calamondins need very little water in the winter. I have a very fast draining soil, sand and bark and bit of coconut husk.
I'm not sure how the roots are supposed to look. They seemed like they might have been packed too tightly, maybe in a bit of a rounded ball. I last watered it after re-potting 4 days ago. I ended up putting about twice the amount of water in to get the usual amount of drainage I get through the bottom of the pot. I assume that was because of the recent re-planting. The soil is still visibly wet all the way to the top four days later. Should I more aggressively prune the roots, do you think? How do I proceed if it's a drainage issue? I have only fertilized twice since the winter started with 20-20-20.
The 24-8-16 fertilizer would be better if it contains micronutrients. I don't think the leaf damage is due to fertilizer burn. Is that the space heater at the bottom right of the first photo? Perhaps the damage is from the drying effects of the rising heat. Spider mites are difficult to detect during the early stages of an infestation. They can be seen as tiny specks of red with the naked eye, if you look closely. The glint from light hitting single strands of webbing usually gives them away during this time. You could place a sheet of white paper underneath some foliage then tap lightly on the stem. If there are any, they'll fall onto the paper and be easier to spot. Vancouver has soft water so don't bother with the vinegar.
Thanks for the tips guys. I think the tide has finally been stemmed (pun intended) with respect to the lost leaves. For anyone troubleshooting this problem in the future, here's my theory: When I recently moved into a colder, dryer apartment with less sunlight, the overall function of the tree decreased. I continued watering him as I had been: Every time the top bit of soil was dry. Watering this frequently was find in my old, sunny, warm apartment meant that he was still sucking up the water beneath the top inch and his roots were getting relatively dry every so often. In his new situation, however, I think water was building up in the roots - which never dried out - and he suffered root rot and lack of oxygen. When I last re-potted, I didn't water him until the soil had completely dried out. It took 15 days! As his roots dried out, the rate of leaf drop went down amongst the sturdy lower leaves, and the "drying out", slow yellow-y death stopped amongst the newer, higher, larger leaves. When I finally watered him (with a little 24-8-16), he actually started some new growth in about 4 places up top. All of the new growth is looking good about 5 days later. So the lessons for a Calamondin must be: 1) Wait until the entire root system is relatively dry before watering, not just the top couple of inches. Stick a chopstick in to determine how deep the moisture is. 2) It will take a lot longer for the root system to get dry when the tree is relaxing in winter mode. 3) At least once per year, let the entire pot get almost bone dry, then water with fertilizer to promote a major growth period. Maybe these are obvious to some of you. My last question: Most of the leaves that have dropped have been in the bottom 2/3rds of the tree. It's left him looking like the attached picture. I have a bar-style light so there is plenty of (artificial) light getting down tho the lower branches. I've cut off all of the dead wood. Now that he's happy, is there anything I can do to encourage growth down in these lower, twiggy areas? I'd like him to get to being thick and bushy within a year or so if possible. Thanks in advance.
It appears that all of the lights are located above the plant, and heavy top growth is shading out the lower levels. You won't get more leaves down there without thinning out the top or adding supplementary lighting underneath.
This may not be advisable. The instructions on the label of the fertilizer I use warns against fertilizing when the soil is dry.
Just a thought. when you got the 26 watt compact flourescent bulb, did you check for the colour temperature number. It is most often found in tiny print on the base of the bulb above the metal threads. You can get them now with a colour temperature of 6500 K, [ stands for Kelvin but don't worry about that].. these are about the closest you can get to bright daylight, and will fit in inexpensive clamp type lamp fixtures which you could place to get some light lower down and close to the tree. You might want to consider plugging all the lights into a power bar and plugging that into a timer, and then you could program it to turn on and off regularly, which would be easier for you and better for Sir Balzac :-). Just a suggestion.. I have my light garden fixtures set up this way and now I don't have to worry about forgetting to turn them on and off and the plants get a regular dose of light every day, about 14 hours or so.
