This Washington Navel was repotted in CHC (Millet's mix, or as close as I can get to it) about 6 months ago. It did well initially, very full, no leaf drop over the winter. Beginning in February, it started dropping leaves. I thought (hoped) that it was just normal leaf drop, as the leaves weren't very yellowed and the petioles remained attached to the leaves. It broke bud about a month ago, and new growth began, but then it started dropping leaves like crazy, and there is some stem/branch dieback, too. Old leaves, apparently healthy, dropped without the petiole attached, and many of the new growth sprouts died and dropped off as well. You can see that the leaf drop spares this one pendulous branch. The leaves on this branch are huge, as big as my hand.





There was an orange the size of a softball which dropped today. There is no drooping or yellowing or significant discoloration of the leaves. I gave it a good soil flush today thinking maybe it was salt toxicity. I carefully checked the CHC medium, and the plant appears to have sent roots well out into the CHC mix. My Calamondin, Satsuma, Valencia, and Nagami kumquat are all in the same mix and all have anywhere from a tiny bit to substantial new growth and no leaf drop.

Any thoughts are appreciated. Robert

Growing citrus is such a challenge, isn't it? I don't know the reason SB but I did notice the heaters close by. Just a thought, & my 2 cents worth.

Thanks, Patty. That would be great, I suppose, if it were an environmental factor like that. That particular heater has come on only maybe twice in the past month, but I keep the fan on most of the time. And the Calamondin next to it shows no signs of injury.

I moved the tree after I flushed it, for other reasons. I hope you are right, because if so, maybe I already fixed the problem, and the tree may recover.

SB

You know, I just noticed that your leaves are falling from top & not bottom. Usually they drop from bottom branches & go up (at least mine).
Do you remember my limequat I posted last Feb (I think) & almost all leaves were gone? Well, it lost all leaves & I had to cut dead branches till there was only a 8 inch stub above the graft...looking dead. It now is leafing back out. Flushing soil always seems to help, so hopefully yours will branch out again. (Millet says to flush 3 times the amount of pot)

This is a follow up on the Washington Navel. Here is the tree today. It appears to have made a decent, but unspectacular recovery.

Why is the tree staked? SB, the container seems too small for the tree. The most important item inside of a container, from the surface of the soil to the bottom of the container in my opinion, is oxygen, oxygen, oxygen. If you slip the tree from the pot, are the roots circling around and around, the inner walls, and if so, do you see many white growing tips on the root ends, and if so how many? I wonder what the growth medium's temperatures were 1/2 inch in from the container's sides, on the sun side and on the shade side of the container, and in the middle when the leaf drop occurred? What are the temperatures at the present time in the mornings? The leaf drop had to be from either, a large temperature difference between the leaf surface on sunny days and a low temperature in the root zone, or high soluble salts (however I don't think this was the problem), low oxygen/high carbon dioxide in the small size container. That size tree now would do very well indeed growing inside a Root Builder (air pruning Container) up sizing using the 4-inch rule. It would stop any circling, and multiply many times the white root tips. I just transplanted a Fina Sodea Clementine into a Root Builder container yesterday, applying the 4 inch rule in my upsizing. I used a 18 inch high Root Builder container that contained 864 air root pruning projections around the sides. Your tree does look a LOT BETTER. BTW, you really have a nice looking greenhouse. What size is the greenhouse? - Millet

Millet, the tree was staked for support early. There are no ties holding the tree to the stake anymore, I just haven't bothered to pull it. Maybe I shall do that tomorrow, along with peeking at the roots.

Thanks, the GH is 20' x 23' mostly dedicated to tropicals, particularly tropical fruit.

PS: I monitored the tree soil temps pretty closely and I didn't note any problems. I had concluded that the heater was the problems, as suggested by Patty. Once I moved the tree from that position, the leaf drop ceased and the recovery began.

Could possibly be much the same thing as the leaves being warmed in the direct sun. I really don't know because you state that the heater was only on briefly on just two occasions. In this case the heater was probably heating the surface of the foliage, and also some leaf desiccation from the warm air stream coming from the heater vents across the leaves, while the soil in the container was setting in the shade of the side wall. Trees almost never lose leaves from WLD when the soil temperatures within the container are at or near 64F. Anyway, very nice looking greenhouse, that you can certainly be proud of. - Millet