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naplesgirl_gw

key lime leaves yellowing & falling off

naplesgirl
14 years ago

Hello, I did a search and found a few posts regarding key lime problems but most of these were from members who were growing the trees inside or in pots, so wasn't sure they were relevant.

I purchased a 4' key lime from a local nursery about 6 months ago. It seemed to be doing fine at first (planted outside in ground) but then dropped quite a number of leaves and the leaf edges starting turning yellowish in spots along the edge not attached to a branch. This spring, it flowered profusely and there are quite a few teensy little limes (about 1/8" diameter) on it, and a couple large ones (about 3/4"-1") but the leaves are very sparse and still yellowish along edges, and I have seen no new growth of leaves. I have used citrus fertilizer once monthly since planting & water 1-2 x week. There is mulch (oak) about 4-5" deep at dripline but shallower (1-2") at trunk.

Any opinions of what's wrong? Too much water? Too little? Supplements needed? Not enough sun? Too much sun? (It is under the canopy of a 25' yellow jacaranda which had only bare branches up until about a month ago, so it was getting full sun pretty much all day, but now only filtered sun til early afternoon, when it gets full sun again.)

Any suggestions gratefully accepted - I don't want to lose this little guy!

Here is a link that might be useful: single leaf pic here

Comments (8)

  • rhizo_1 (North AL) zone 7
    14 years ago

    Mulch should never be applied anywhere near the trunk at all, and should not be used in layers any more than 2 to 4 inches.

    Too much of almost anything isn't a good thing, and that's waaay too much mulch. You'd be shocked at how much water (in terms of irrigation or rainfall) it takes to get through that much mulch. A steady hour of rain might not even see the soil system. Your efforts at watering might very well be soaking the oak chips while the soil/root system remains dry.

    There's also the oxygen issue. :-)

    My advice would be to rake away the chips from around the trunk and get rid of all but a couple of inches elsewhere. By the way, tree roots will advance far beyond the drip line of any tree, so you may just want to spread those chips out in a much wider radius from the trunk.

  • meyermike_1micha
    14 years ago

    Hi,

    To add to rhizos comment, by putting down so much mulch, you are encourageing the roots to grow shallow and not deep.

    I use to be a landscaper, still am at times, and we never put more than an inch or two of mulch around any tree.
    Around flowers and shrubs that by nature put out shallow roots, that is a different story.

    The roots will be looking for water above the ground in the damp mulch instead of encourageing to grow deeper looking for moisture in the ground.
    If you are not getting enough water into the mulch at times to satisfy these shallow roots you would encourage, then you are talking about a really thirsty tree..

    Mike..:-)

  • naplesgirl
    Original Author
    14 years ago

    Thank you, rhizo & Mike, I appreciate the input.

    However, I do not believe mulch is the problem, as when I first planted the tree - and up until about a month ago - there was no mulch whatsoever around it and the leaves looked the same as in the picture I posted...

  • meyermike_1micha
    14 years ago

    Ok..I am going to make a bold statement, not on what I believe, but what I have seen..

    Count the too much sun or not enough out.....I have property in the Carribeans, where I have citrus growing under trees that are greener than the ones in the sun all day.
    The leaves are always yellowy on the ones in the all day hot sun, but produce lots of fruit and flowers. The ones under the trees, produce lot of green leaves, and less fruit and blossom.

    1. I would first check the soil and make sure your roots are evenly moist, not wet or dry. If the soil is cruddy, then amend it for the roots sake. It has to be well draining and not compact, or it will affect root function causing all these problems. While your at it, take a gander at the roots. They should be whitish..

    2. I would then check the next most important thing you can do to keep a healthy tree, your PH. If your PH is not on the acid side, no matter how much you fertilze your tree, it will not take up nutrients properly.

    3. Next, check for bugs. If it is being attacked, the leaves will fail, turn yellow and drop.

    Almost always though, the most common casue of problems for citrus is unhappy roots or the wrong PH. Usually the "soil" which causes your roots to fail and not to their job....

    As for the sun, too much or to little, I have many that are perfectly healthy here and on the islands that are very healthy in either or.
    My problems along with my friends in Florida have always been root related due to poor watering habits, or poor soil, or root rot.

    Attack these three first, then make your next move. Forget the fertilzer for now. Please, make sure your roots look good and are doing their job first, before applying fertilzer. They could become toxic instead of beneficial such as happened to mine in the past.

    Roots should look white and soil should be well draining..:-)

    Once you have done this and all is ok, we can come here and suggest some great fertilizing methods for ya..ok

    It's not to late.

    Hope this helps you rid one problem at a time.

    Mike..:-)

  • naplesgirl
    Original Author
    14 years ago

    Thanks again Mike!

    I will definitely check the roots for color and condition.

    Since my "soil" - if you can really call it that - is mainly good old Florida sand (although when I dug the original hole for the tree, I added a bag of manure & mixed in since sand has so little organic matter to offer), I doubt drainage is the problem.

    Also will check pH, but I'm pretty sure that's going to be acidic, as my back yard gets tons of oak leaves from my own & neighboring trees. No pests evident, either... the mystery continues. LOL Will stop fertilizing also, just to make sure, at least til I check roots.

    I do appreciate your help!

    ~kathy

  • meyermike_1micha
    14 years ago

    I think you might of nailed it if once you look and your roots and they are ok..Also if your trees are being watered correctly. If it is fast draining and soil stays moist to dry in between rains and hand waterng, you are fine.

    Sand hold NO nutrients, and does drain very well, in fact to fast, taking all nutrients away from your trees too...I would guess it is now nutritional problem.

    Now you need to address fertilizing.

    If I were you, I would hop over to the container and fertilizer forums to learn about fertilzers, and or call your local extension service or a local orange grove seller and ask them how or what they do to fertilze in ground citrus.

    You could probably get a well balanced fertilzer with all the micros needed for vitality. They also "need" calcium and magnesium....You can get Mag from epsom salts and calcium from gypsum..It is all explained in the container forum.

    I can't tell you exactly what to feed because I do not know your growing conditions, nor do I grow inground, just containers.
    I am sure someone here is going to give you great suggestions if everytghing your saying, such as your roots and watering and soil are ok..

    Let us know what happens.

    You might get a faster answer if you start another thread asking specifically on how to apply proper fertilzer or what to use for inground grown citrus.
    Many may not come here and see your plight if it is a fertilzer issue..
    So start a new thread ok...

    Good luck..

    Mike;-)

  • meyermike_1micha
    14 years ago

    Let me correct that.
    I have some that grow inground, but on the islands where I can only see them every other year or so..
    But boy, have the insect ravaged them!!!
    Amazing that they still survive even with no attention..lol

  • meyermike_1micha
    14 years ago

    So how's it going by now? I hope well naplesgirl!

    Boy, would I love to be in Naples right about now! I would get more sun there in just one week, than the entire month of June and July put together...:-)