Is my calamondin orange tree dying?

I have a calamondin orange tree (Fred) that's been in our family so long that my 38-year-old daughter calls him "my older brother," so I'll refer to "it" as "he" here. :-)

Fred has been a treasure ever since I bought him in Florida as a little take-home almost 50 years ago. My understanding is that calamondins don't live this long, but I'm unwilling to give up on him. Here's what's going on (and I can send photos):

This past summer Fred was on sabbatical on our sunny porch, like every summer, and he was doing great. We moved him in for winter (we're near the Smoky Mountains in EastTennessee, so he can't stay out). Last summer we had our large windows coated with the plastic that keeps the rays out that fade furniture, etc. About December he wasn't looking as "perky" leaf-wise as usual and also wasn't blooming. He began dropping leaves and had been for weeks. I finally realized there might be lack of what he needed, so I moved him by a non-coated sunny window a month ago, so far to no avail.

Last week I changed his soil, using the proper mix (1 part each all purpose sand, peat moss, good potting soil) and watering thoroughly once a week, as always. Some leaves look healthy right now but others are curling and drying up daily. When the weather's 50 degrees or above, I've been putting him on the sunny porch and moving him in at night. So far I can't see any new growth. Though he's probably about 5 ft tall, he only has about 240 leaves when he usually has 3 or 4 times that. Should I cut away the bare stems? Anything else????

I surely hope he isn't dying of old age. Help! (I do have some photos.)

Thank you for any advice!
Brenda Rollins

 

Your potting mix is not the best for citrus--they like a much chunkier soil with lots of air space (I use 4:1 pine bark to potting soil).

The leaf drop may have been due to the cold root--direct sun scenario talked about often here--especially during winter. Citrus roots are completely inactive at temps below 55F. If the leaves are exposed to direct sun while the roots are cold and cannot supply cooling water the leaves get cooked and drop--sometimes weeks later.

You have 2 choices-- keep it out of the sun when the roots are cold or heat the roots (ideally to at least 65F).

 

It might benefit from a good pruning when you put it back outside along with what skeeterbug mentioned. At one point mine was looking thinned out and now it's bushy again from the pruning.
I have had mine for over ten years or so. I can't ever bring it into the house because it would drop most if not all of it's leaves (too warm/low humidity) It lost so many leaves, not to mention any small green fruit it had.

It always spends it's winter now in a heated 50-55 degree garage in front of a northern window.
It has two ripe oranges and a lot of tiny green ones from last summer's flowers. By rights it should have more ripe fruit, but because of those nasty spidermites last year, it was cut again way back for the second time in two years to help get rid of them along with daily soaping and water sprays from the hose!
All the leaves and all the fruit stay on the tree when it's in a cool environment, so that's where it stays, then back outdoors in the spring/summer. It gets a good drink when the leaves "slightly" bend down a little.

 

Most people do not realize that citrus trees do not really need much light--they actually hit their maximum photosynthetic level at about 1/3 full sunlight (about 650 PAR). When they are dormant during winter they really don't need much at all.

In the mild winter we have here in N Florida, I have come up with a novel way to avoid winter leaf drop--I leave my container citrus outside under a shade cloth. I only put the containers inside when the temp is going to be below freezing (except for my key limes--which I was bringing in at temps below 40). However, even mid 30s has not caused a leaf to drop on any of my container citrus even the key limes as long as they are under the shade cloth when the sun hits them in the morning.

I actually started putting them under the shade cloth to protect them from the summer heat, but as winter approached I was not seeing the droopy leaves I saw when they were outside last year on cold mornings. I actually got at least 2 flushes from most of them between Nov and Feb while my inground citrus were completely dormant--probably due to the sun warming the black plastic pots.

Skeet

 

My hunch is the leaf drop is the result of insufficient light because of the new window coating. If you've had success in growing this tree for 50 years and this is the only thing that's changed then the window treatment is the likely suspect. We don't know the nature of the coating, how dark it is and to what degree it filters out ultraviolet light. So while it is true about citrus not requiring full intensity light, as skeet noted, the effects of the coating must be taken into account.

You should reduce watering as less moisture will be transpired due to the loss of leaves. Also, do not water on a schedule but only when the soil is dry. Dryness can be determined by checking the top few inches of soil or by the weight of the container.

The time spent outside in 50F temperature would not have helped. As explained by skeet, the imbalance would result in further leaf loss.

Do not remove the bare stems if they are still green. Only do so for the ones that are brown, dried, and obviously dead.

I was reminded of a similar thread from last year while composing this response. The OP had a problem with a droopy calamondin and the discussion drifted onto the possibility of insufficient light beginning with this post by mr.shep in droopy calamondin | Page 2 | UBC Botanical Garden Forums. You may want to have a look.

I wish you luck with this very special tree.

 

Skeet is correct when he notes that the new growth medium you transplanted your tree into is not a good medium for citrus. What your growth medium actually is, is 1 part all purpose sand, and 2 parts peat moss, because common retail potting soil is almost 100 percent peat moss. Another problem is the current care that you are giving your tree, and that is your watering. A growth medium like the one that your tree is currently planted in, with such a high peat moss concentration, unfortunately holds an over abundance of water, and sacrifices much needed aeration. Further, because your tree no longer has a dense foliage canopy, the trees respiration rate has dropped dramatically, thus the tree DOES NOT require, NOR WANT, much water. Remember, over watering is THE NUMBER 1 KILLER of containerized citrus trees. I also use a 4:1 "potting soil" mix (1 part Coconut Husk Chip and 1 part peat moss), a blend very similar to Skeeters. Citrus trees are easily able to withstand hard pruning, but I don't know if I would prune the tree back. Pruning would further reduce the balance between what little foliage is remaining on the tree and the root system. I think your tree already has enough problems at the present time. If it was my tree, I would repot the tree into a medium that provides the root system with rapid drainage, and HIGH air porosity, then I would water tree sparingly. I'm sorry to tell you that it could already be too late for your tree's root system. What every you do you better do it rather quickly. Good luck to this tree. - Millet

 

Everyone,

I am very grateful to all of you who have been so kind to take time and try to help "my Fred" calamondin! I have copied and pasted every reply onto a document and I've been studying them carefully.

I have already done a repotting with the 4:1 pine bark to potting soil recommended, and I have moved the tree to another inside location (away from the film coated windows that keep "bleaching" rays from the furniture and the hardwood floor), a small breakfast room with windows. So from one side Fred has morning sunlight for the better part and hour and then later in the afternoon, some sun comes slanting in from a window on the other side for perhaps 30-45 minutes. Also, on a warm day recently, I sprayed for spidermites, as a precaution.

I am also going to be VERY CAREFUL about watering...among other things you've suggested.

There's some scarring on some of the leaves that may be caused because of some windiness from the day I put the tree on the porch for sun. In warm months and summer, we have always put Fred out on our open porch, where he flourishes. But I certainly won't put the tree out there again till consistently warm days are here !) If I can figure out how to submit several photos to you, I will do so in the next message.

Thanks thanks thanks!

Brenda