Our lemon tree has had some leaves turn yellow recently. I am not sure whether this is due to underwatering or overwatering or some other cause but I would like to remedy it. The soil is pretty damp about an inch below the surface. Our neighbors have a very nice large lemon tree so I know it's possible to grow them well here. Do you have suggestions?

A friend also mentioned we should prune it, and I'm not sure of the best way to do that, but the branches do droop a lot when they have lemons on them.

The tree is against a fence on the north side of our yard.

My goodness, it took quite a while to find your question, Kevin. This veggie forum isn't awfully active in the winter, so in future it might be better to post to the "Ask a Question" forum.

Your lemon looks to me as if it's suffering serious nutrient deficiency. Have you been fertilizing it regularly? Don't forget growing a tree in a pot, it will use up all the nutrients in the soil pretty quickly so you need to replenish them regularly.

I'd advise you to try re-potting it in a wider pot with fresh, good quality potting soil, first. Usually potting soil will have a mild dose of fertilizer in it (check the label) so the new soil will give your little tree a boost right away. If it doesn't, you will need to give it a very light dose of fertilizer. Get yourself some citrus-specific fertilizer, and set a reminder to fertilize this little guy regularly according to the package directions. But adjust the amount a bit to compensate for it being in a pot, not in the ground. Fertilizer disperses more widely in the ground than in a pot, so give maybe 1/2 to 2/3 the amount they specify.

The reason I specify a wider pot is because citrus tend to make a wide, shallow mat of feeder roots near the soil surface, so when you take it out of the pot you may see a lot of roots around the perimeter at the soil surface.

This is a very tiny tree and you don't need to prune it. Some people think pruning is The Answer to every woe. With citrus, they're slow-growing enough not to need much pruning until they're getting really big. Especially lemons, which tend to stay pretty small.

Hi Elaine,
Thanks for the reply! We have not been fertilizing it. How often would you recommend we do so? I have some 24-8-16 plant food, is that OK or should I get a 10-10-10 (is that the best recommendation for citrus?)

Thanks,
Kevin

You have to be very careful of fert with a high first number like your 24-8-16. In a pot, the fert hangs around the roots more than it does if the plant is in the ground, where it can disperse.

Best to get a granulated formula that is specifically for citrus, and has all the nutrients and trace elements needed. Use it about half strength because you're growing in a pot. Please don't get sucked in by the idea of "fertilizer spikes" because they arenot a great way to deliver fert to any plant, but especially bad for citrus because they have a web of fine feeder roots all around them near the soil surface, and the finer the roots the easier they get burnt by too much fert in one spot.

Depending upon what fertilizer you get, generally citrus are fertilized here in early spring (now) early summer and early fall. Not in the winter.

But re--pot first and let the plant recover a bit before you give it fertilizer.

Thank you... my wife just vetoed repotting, so we might just try to muddle through with the pot we have. I could potentially introduce some new soil by digging out some of the soil around the sides and replacing with fresh soil. Thanks for the tip about the spikes, will stay awy from those.

Be very careful doing that, because of the danger of damaging roots with tools. Better to lift the whole plant out of the pot, add a couple of inches of new soil in the bottom, then gently rough up the root ball with your fingers, set the plant back in the pot and sift new potting soil down the gaps in the sides. Water it well before you do this, and be sure it's all moist after you're finished, too. Then keep it in the shade for a few days after.

That is not a nutrient deficiency. On citrus trees they are very easy to diagnose: green veins on a yellow leaf means iron deficiency, while old yellow leaves and green new leaves mean nitrogen deficiency. I don't see either. This doesn't mean citrus trees don't need fertilizers, far from it. In fact citrus farming is where the present generation of leaf spray fertilizers were first widely used with success. I suggest you check into those for the future: I've been using them for over a year now on other crops and they are amazing products.

This is a watering issue: in the specific the tree is dying of thirst. People assume that just because citrus trees are grown in very hot locales like Andalusia and Sicily they are drought tolerant, but they are just the opposite: they need lots of water to thrive and lots and lots of water to do well. And in the top picture it seems to me the potting compound is as dry as bone.

Finally another note: differently from ornamentals like camellias, citrus trees don't like small containers. Get a larger container for it.

I'm not sure that diagnosis matches because the soil has been damp an inch below the surface every time I've tested it. If anything I'm concerned about overwatering.

> old yellow leaves and green new leaves mean nitrogen deficiency

This does seem to match the pattern? The leaves near the tips are green and the leaves closer to the base are yellow.

I wouldn't exactly define that new(ish) growth as "green", but colors are very subjective.

It's literally impossible to overwater a citrus (or almond) tree: they will take as much water as you can give them and clamor for more. What can happen is water stagnating in the undervase or in very thick clay soil and starting root rot, but the symptoms just aren't there. No, this is a watering issue.
Remember that citrus trees have what I can only call an inflexible watering schedule: you cannot even really rely on rainfall for it. They are not hard plants to grow, but this tight watering schedule require a lot of dedication, especially considering accumulate drought damage can kill the plant.

There's also the issue of the small container: I don't think your tree is rootbound yet, but it surely isn't having the time of its life. there.

Okay, I got some citrus potting soil and tried to tease the plant out to put the potting soil in the base and around the sides. Unfortunately I was having trouble getting it out. A fair amount of dirt came off the top though when I rolled it on its side, so I took that opportunity to put some potting soil in the top and around the edges. I also added fertilizer last week

My eyes may be tricking me, but I think I am seeing more green in the leaves today...

I had a few lemon trees that did nothing for years. I got fed up and gave them fertilizer last year. This year they all bloom like crazy. Try this, try that was my way.

Nobody around here has citrus potting soil. Does anyone know if there's a near match to it that Walmart usually carries? Or maybe..."just you whatever I have"? We've thought about planting it in the ground but I think the varmits and cold weather might do it in.

I've been promising our little Meyers that I'd pot it up from it's greenhouse container that it came in. Of course I've been saying this for the last 4-5 years. We made 9 lemons last year but this is after the squirrels(?), deer(?) pruned off some blooms and branches. Just looking at it now it has lots of buds on it. Got the yellow leaf look, too. This lemon tree has not seen a lot of fertilizer.

Ed, potting mix for citrus is cactus mix.

Yes, I understand. But two Walmart's and a Lowe's Within reasonable driving distance do not have it so I'm looking for an alternative.

After looking around it looks like 1/4 each of sand, perlite, compost, and peat make a basic citrus potting soil. So, I think I'll take a volume of good potting soil and add to that an amount of sand that equals 33% of that volume.

I may have worried prematurely... it has really taken off in the last month, though I did add fertilizer in Feb (planning again in May and August) and a few inches of citrus potting soil on the top and sides. No fruit but I assume it will be coming shortly

Great! I can see that there's new growth.

Mine is looking better, too. Kinda...

I did repot it with a mix of Bacctos potting soil and some soil from my garden. He greened up and loaded up with blooms...dozens of them. Then, we had some storms pass through and we lost most of the blooms and buds. Seems the first set of blooms last year got knocked off (or fell off ???), too, but bloomed again and set some lemons. There's still some tiny lemons or old receptacles that will fall off. The weather has been up/down/rainy/cloudy/etc.,. It seemed early for so many blooms so I hope it'll bloom again. We'll see.