I'm growing an improved (grafted) Meyer lemon in a pot. Purchased back in the spring. It's been outdoors all summer and even bloomed enough to produce a still-small lemon. I've brought it in for the winter and it's currently residing in my little heated hobby greenhouse where it would get the most sunlight. I've noticed that the veins on some of the leaves are yellowing and then the whole leaf yellows and drops off. Is this a result of the changing seasons, nutrient deficiency or too much water? I have fed it twice with Epsoma Citrus-Tone - once when planted in the pot and again 2 months ago. Any help is greatly appreciated.
What type of soil you have in it? Does it stand all the time wet, or do you let the roots dry a bit within waterings? Sometimes is best to take out the first fruits so that the energy of the tree is wasted on better rooting system and the leaves. How big is the tree compared to the pot? what pot you're using? I've noticed that depending on the pot the substrate should be changed a bit. I personally use compost and 1/3 of river sand and it helps me with my citrus trees on pots. When they get to a big pot (5 to 10 gals) I would add more porous stuff on bottom, believe it or not styrofoam.
The leaf-yellowing has slowed down and I've moved my plant into the house. I had heard that they don't like hot or cold drafts so it's easier to protect it indoors even though the direct sunlight will be reduced. I also amended the soil in the pot - basically repotting it - and adding more compost. It was originally planted with Dr. Earth potting mix along with worm castings and fertilizer in the spring but probably needed some additional nutrients as well by now. The roots are not pot-bound and still had room so I didn't root-prune it. Can't remember what size pot I used but I did purchase the recommended size for a two to three year old tree (which is what I bought). It now gets misted every morning when I open the curtains. It hasn't ever sat in water but I added some gravel to the saucer to raise the pot up for insurance. It gets watered once a week so the soil is dry when it does get watered. I had also heard that it's not uncommon for citrus trees to drop some leaves but of course, I don't know what's excessive leaf-drop at this point.
Love them meyeri trees :) fruit is so big and juice when you cultivate them and let them ripen on the plant... I bit of leave lost is never a bad thing, the plant will be adapting to the temps and it looks that with your care it will get better and better.
Greatest thing on citrus is that when they get older they become more or less indestructible (by any pests)
I suggest that you also try a nice compost tea for it. A plant with micronutrients tends always to be healthier... when something is not in the soil, and the plant needs it, that's when probs come.
I think that the plant might have only been affected by the temp stress. But it's always good to ask to a gardener in your area. I did got bit of that black mildew (don't know the name in english) on one of my meyeris that are in situ this year... was as simple as a soap, oil and water mix ,and then caressing the leaves with care. Ussually diff flies take care of that, but on this plant there was an ant pile very close, and where there are ants, the other flies can't do their work :p ... and the plant got it from an old valencia tree... but since the tree is already old, it handles anything by its own, but the poor meyeri was only 1 year old. It loosed a couple leaves with the treatment, but now it's back and producing more branches... now it will be a matter of waiting for the right moon (if you believe on that) and decided what branches I want to keep.
It's good for citrus (and most trees) to have a nice airflow on them branches... since citrus are more like a bush/tree hybrid it's always goo to train them
You could also do a worm castings tea as well, but since it already has been newly replanted it can wait easily a couple more months... sorry I couldn't be of any more help.
Please send a pic so we can see it ^___^ sending it good vibes from here. Hope it gets to be a great producer
Thanks, Plancton, for the tips! The leaf drop has stopped after losing about 10 leaves except for one branch - the one with the big ripening fruit. The leaves on that one branch aren't quite as green as the rest of the tree. Wondering if I'd lose that branch once the fruit is ripe enough to pick. I did tip prune just a bit to get my lopsided tree in balance and snipped off a few of the thorns to protect my fingers. I figure I'll give it some compost tea in another month or so (have both oak leaf and worm compost). I did purchase a floor lamp for it with five fixtures, all with full spectrum CFLs to make up for the poor winter light here and it's on about 16 hours a day. Haven't seen any mildew on it but our summer was pretty dry.