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Potted Nagami Kumquat needs new soil

jenn
13 years ago

We have a potted Nagami Kumquat (the plant tag says "true dwarf") that we bought several (5-6) years ago. The pot is one of those lightweight foam terra-cotta look-alikes, about 15-20 gallons. The plant is still in the same potting mix since it was planted. I used a good commercial bagged potting mix topped with a layer of small bark mulch. It has gotten monthly (or almost monthly) feedings of E.B. Stone Organics Citrus & Fruit fertilizer (7-3-3) during the growing season.

After a slow start the first 1-2 years, it has done fairly well and produces new fruit each year.

However, the soil line has sunk to at least 6" from the top of the container (see photo below), and it is time to add and freshen up the soil.

I've been reading about Al's famous gritty mix, and I'm convinced it is good stuff. However, I work full time and have had some health issues lately and would prefer not having to drive all over creation to find Turface and some of the other ingredients at this time -- instead, I'd like to use similar ingredients that are easy to find locally or we may already have on hand. I figure that if the plant has produced fruit every year in the same ol' commercial bagged mix, then it will be fine in a fresh mix of ingredients similar to the gritty mix. :-)

We have several bags of Earthgro Natural Mulch (ingredients = "forest products") that we mixed with sphagnum peat and perlite in our Blueberry pots. The mulch has mostly fine particles with a few wood chips and chunks. I'm considering using a similar mix to transplant the Kumquat into the same pot.

My questions:

1. What ratio of these ingredients should I use? Would 1:1:1 be best?

2. Should we use the same pot, or get a smaller one?

3. Do I need to add anything to green up the leaves, or will the new mix, along with the regular feedings and some liquid seaweed take care of that?

The plant gets full sun in a southern exposure. In spite of our hot summers, I tend to be conservative about watering this pot since it is insulated. Even when I forgot to water in previous hot summers, the soil did not seem too dry.

I would appreciate your suggestions.

{{gwi:579996}}

{{gwi:579998}}

Comments (27)

  • mksmth zone 7a Tulsa Oklahoma
    13 years ago
    last modified: 9 years ago

    if you have a lowes or homedepot near by you can find all you need to make a good soil. My main mix is 5 parts screened pine bark mulch(about 1/4" or less pieces) 1 part peat and 1 part perlite. The key to success is excellent drainage. most bagged mixes will compact and hold to much water which is what might be happening to yours now. You can use bagged mixes but I would add a bunch of perlite to help drainage.

    citrus and blueberries like similiar soils so you idea of using the same could be ok.
    if the roots are pot bound you could prune them and use the same pot just dont do any top pruning so the roots can recover.

    using a good liquid fertilizer with either trace elements or adding them seperate along with new soil that doesnt hold too much water will help green it up.

  • silica
    13 years ago
    last modified: 9 years ago

    mk smith's medium is a good medium for growing citrus. For my trees I use pretty much the same type of meixture. However, I prefer to use CHC (coconut husk chips) instead of bark. CHC holds up to 7 times it weight in water, provides the perfect pH for good citrus growth of 6.5, and provides excellent drainage. CHC is very slow to degrade, therefore a CHC mixture last twice as long as a bark, before transplanting is required. My mix is 5 parts CHC 1 part peat moss. This is a very common with container citrus growers.

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  • jenn
    Original Author
    13 years ago
    last modified: 9 years ago

    Thank you both very much.

    silica -- where would I look for CHC? I read about it in the Container forum.

  • jenn
    Original Author
    12 years ago
    last modified: 9 years ago

    Another question: How soon do I need to repot? I see a lot of tiny new leaves coming out everywhere. Can I wait until later in May (when I'll have a free Saturday)?

  • greenman28 NorCal 7b/8a
    12 years ago
    last modified: 9 years ago

    Hi, Jenn, I would wait until after the current flush of new leaves has finished.
    After the re-potting, however, you'll want to protect the tree from direct sun and wind
    for approximately two weeks. This helps preserve the leaves while the roots are
    colonizing the new volume of mix. Also, hold off on fertilizer for about two weeks
    as well, as soils "low in initial fertility" are conducive to root-growth.

    I would use Bark rather than a coconut product, as well.
    Bark will provide the acidity that Citrus prefer, and you can use Dolomitic Lime for an easy
    pH buffer and Calcium source. With coconut products, you can't use the Lime.

    Bark contains suberin - sometimes called "nature's preservative" or "nature's water-proofer"
    - and it lasts a long time.


    Josh

  • jenn
    Original Author
    12 years ago
    last modified: 9 years ago

    Thank you, Josh. Now I have some new questions:

    1. If Citrus likes acid soil, and bark provides the acidity citrus likes, then what is the purpose of adding Dolomitic Lime which raises the pH?
    2. If we go on summer vacation and leave the plants for 2 weeks, should we move the potted kumquat into the shaded patio? We don't have it on drip.

  • greenman28 NorCal 7b/8a
    12 years ago
    last modified: 9 years ago

    Hey!

    Primarily, the Lime is a source of Calcium, which is lacking in most fertilizers.
    There are folks who don't use Lime, of course, but you would still be responsible for
    providing the proper Calcium.

    If you leave for two weeks, I'd move it into the shade and arrange someone to water.
    No way to get around watering a plant for that long.


    Josh

  • silica
    12 years ago
    last modified: 9 years ago

    Greenman, I don't mean to be argumentative, but I must answer your post. If you believe that bark provides acidity, then which acid does bark produce? The absolute perfect pH for growing citrus is 6.5, and coconut husk naturally provides that exact pH. So why would anyone add lime (which raises pH), or for that matter an acid. Calcium deficiency is almost never ever seen in citrus, it is extremely rare. I can't remember if I ever heard of a calcium deficiency, unless a grower uses only pure rain water. Even then people who use rain water, always add 10 percent tap water which supplies more than enough calcium for citrus. Nearly 100 % of all well water, and municipal water sources have plenty of calcium for a citrus tree. Dolomite is added for its magnesium content, and not as a buffer. Hard wood bark is never used in potting soils, because it can contain toxic levels of manganese. Therefor only soft wood barks such as pine are commonly used, and with or without suberin soft wood bark, as all organic products, decomposes and needs replaced. Barks have approximately a years time, especially when nitrates are used when fertilizing. Coconut husk chips (CHC) are currently used by a huge number of successful citrus growers, and by the majority of orchid growers. I have containers where CHC are going into their 3rd and 4th year. It is an outstanding medium as it has a natural pH of 6.5, hold up to 7 times it weight in water, extremely slow to break down, and provides excellent porosity and therefore drainage.

  • greenman28 NorCal 7b/8a
    12 years ago
    last modified: 9 years ago

    Adding the Lime assures that the Calcium and Magnesium will be in a proper ratio for plant usage.
    Perhaps my term - "buffer" - wasn't properly used. The Dolomitic Lime raises the low pH of the bark.
    That is what I meant by buffers.

    Now, lest I tread beyond my knowledge, I will see if I can gather more information from Tapla (Al).
    That said, I would assume that tannic or humic acids are present in bark, though I could be wrong.
    Again, I'll find a logical answer to your questions.


    Josh

  • tapla (mid-Michigan, USDA z5b-6a)
    12 years ago
    last modified: 9 years ago

    Actually, the preferred pH of plants grown under container culture is approximately a full number lower than plants grown in the ground, so a pH of around 5.0-5.2 would be much closer to ideal. I prefer bark because it does break down more slowly, and it doesn't have the salinity issues, high pH issues, and high K issues that CHCs and coir have. Commercial ops that choose to include CHCs or coir in their media generally limit the presence to not much more than 10% for the reasons mentioned. A quick perusal of any text devoted to plant production in containers will confirm this.

    Hardwood bark, sapwood and heartwood, especially sawdust, are generally not used in container soils because the composting process ties up N and produces heat that can easily raise soil temperatures by 15* or more - there is also generally a high pH spike associated with the composting of these products, making them ill-suited as a component of container media.

    I agree wholeheartedly that "mksmth's" 5:1:1 ratio of pine bark, peat, and perlite is an excellent choice (I wonder why no one thought of that before now) ;o) , but the gritty mix of 1:1:1 screened pine or fir bark:screened Turface MVP or Allsport:crushed granite or #2 cherrystone would be a better choice & easier to deal with at repot time.

    Al

  • silica
    12 years ago
    last modified: 9 years ago

    Tapla, several thoughts about your post. First, I have read some of you posting on this and the container forum. You have a higher level of knowledge on container growing than the average person. There are several points I wish to point out on growing container citrus. It has long been known that a pH of 6.5 is indeed the perfect pH for citrus trees. If you wish confirmation just look it up the the book The Genus Citrus, or look up posting on this site by Dr. Manners. Many people think of citrus as being an plant that likes acid growing conditions, which if you know citrus it is not the case. A plant preferring 6.5 pH is certainly not considered an acid loving plant. If a citrus tree is grown to acid, such a 5 pH the tree will produce less and less fruit in direct proportion to the reduced pH level. Concerning the K, and salinity, of CHC is not a problem. Three rinses, and a cation exchange with calcium nitrate and magnesium sulfate (Epsom Salts), easily takes care of it. Lastly, where you got the information that commercial growers that use CHC only include a 10 percent content in there mix, is not the case. commercial orchid growers commonly use mixes consisting of only coconut chips and 1/4-1/2 inch perlite. CHC peat is excellent for citrus.

  • tapla (mid-Michigan, USDA z5b-6a)
    12 years ago
    last modified: 9 years ago

    Citrus aren't unlike other plants in that they are better able to utilize nutrients in containers at pH levels considerably lower than what is considered ideal in the ground.

    In the ground:
    {{gwi:2916}}

    In containers:

    Generally speaking, media pH takes a back seat to soil solution pH as well.

    The information re the chemical properties of coir & CHCs can be found in texts like "Plant Production in Containers II" by Carl Whitcomb PhD, and in "Growing Media for Ornamental Plants (and Turf)" by Handreck & Black, an excellent reference for container culture.

    AL

  • jenn
    Original Author
    12 years ago
    last modified: 9 years ago

    My head hurts, LOL, but you guys have turned this into a very interesting discussion.

    I might be over-thinking this. The Kumquat has been in the same ol' commercial potting mix for at least 5 years, after all, and while it doesn't look very good (yellowing on leaves, sunken soil), it does bloom and produce fruit each season. It seems that either of the recommended mixes could only be an improvement.

    We have a mature (about 40 years old) Tangerine tree that grows in the ground. We have clay soil, supposedly alkaline (we've never had it tested). The tree is a prolific producer, either loaded with fruit or producing blossoms or the next fruit. My husband occasionally tosses a couple handfuls of organic citrus fertilizer on it. Maybe I should just plant the Kumquat in the ground! :)

  • silica
    12 years ago
    last modified: 9 years ago

    Jean, check what rootstock your Kumquat is growing on. If the root stock is poncirus trifoliata, than it should do well in your clay soil. Tell your husband that a mature citrus tree (any variety) planted in the ground needs to be fertilized 3 times a year (March through August).

    Tapla, I also have the book "Plant Production In Containers-II" by Dr. Whitcomb. I would categorize the book as excellent in places,and the reader can learn a lot from the book. Dr. Whitcomb's book also contains a lot of self serving promotion for his air root pruning container business.However, all in all it is worth the purchase price. Looking at the two pH charts that you have provided, I would say that the charts promote 6.5, rather than 5.5 as the perfect pH for citrus. A pH of 5.5 supplies to much phosphorous, especially for containers.. Citrus use very little phosphorous. The root system of a citrus tree absorb nutrients in a 5,1,3 ratio. Therefore, when the roots absorb 5 unites of nitrogen, they absorb only one unit of phosphorous and 3 parts of potassium, plus of course the trace minerals. Discussing this issue with you has been a pleasure, as you seem to have a lot of book knowledge concerning container culture. However, I think any further discussion would just be beating a dead horse. Regards to you.

  • meyermike_1micha
    12 years ago
    last modified: 9 years ago

    Silica:

    Your intentions in my opinion, are very good and I find your desire to share what you know,do and your experiences very informative.

    I was having a very interesting read of this thread until I got to the last part of your post Silica, until I saw you say that talking to 'Al' is like beating a dead horse.
    Why?

    I found your postings infact pleasant and quite respectful, until you said what you said. To me, in around about way it seems that you insulted a very well respected man, teacher, mentor, instructor with many years of experience in this field, and member here.

    How can anyone respect or learn from those that seem to withdraw from conversations when they react this way or back off when they find that someone makes them feel uncomfortable by sharing a different perspective?

    I have never seen Al back away from any conversation when talking facts and about science in the face of opposition or differing opinions as he continues to enlighten us with much scientific facts, illustrations, documented facts, proven results, and troves of info, while others just abruptly stop and walk away?

    It frustrates me to see this and limits the choices of many to the few that stick by these threads and continue to do their their utmost to educate us in the face of opposition with sciencetific reasonings and proof.

    My possible desire to use CHC has again been pushed back even further.

    Mike

    I/we do not get it.

    Thanks anyway for the small amount of info I was able to disifer and thanks Al for not initiating a quick cut off from what i thought was a pleasurable conversation betwen two side of teh spectrum. Best regards to you:-)

    Notice that I havn't had anything to say about CHC lately although they have been discussed? I do though abouut the way many present their cases with the stuff, and it has been a turn off for me.

    Thanks

    Mike

  • meyermike_1micha
    12 years ago
    last modified: 9 years ago

    Sorry.

    Somehow the post was submitted without my ability to proof read and or add my other though. I opologize too for wording and spelling errors in which I am sure there are some.

    Until I see anyone that can prove Al and or others wrong with the use of bark and it's wonderful properties, I will stick with using bark since CHC have never benefitted my trees to any degree like the mixes composed of mostly pine or fir bark in which my trees are thriving in.

    Mike;-)

  • jodik_gw
    12 years ago
    last modified: 9 years ago

    Al is not only a long time member here, mentor and teacher to many, but also a very highly respected, knowledgeable, experienced grower of containerized plantings, bonsai and tree grower extraordinaire, and a frequent key speaker at professional grower/garden events. He's considered to be a trusted source of vetted scientific information and experience where growing and plants are concerned.

    So, to say that Al's knowledge is all book learning, and speaking further to him would be beating a dead horse is rather discourteous, in my opinion, and when Al is disparaged, it casts a disparaging pall on many other people here, as well.

    I agree with Mike... how can people learn if there's no honest debate, if they can't get the information they need to make informed choices? I don't post in this forum often, but I do read. I'm not that knowledgeable about citrus, yet, and I'll be the first to admit it. But when I do finally obtain my first tree, I'd like to learn and share what I know, but how can we do that when valid information is slapped down and we defer to an industry that couldn't care a whit whether our trees and plants die or not?

    In my experience, and through cognitive thought on the issue, coco coir products are not the boon to growers they've been billed as. It's nothing more than a way for the gardening industry to make profit from a waste product. It doesn't have a small "green" footprint it's said to have due to mechanized processing and shipment halfway around the globe, and it's not "saving" our peat bogs, which are in no danger of drying up anytime soon.

    Through my own use of these products, I've found them to be more of a nuisance, requiring overnight soaking, at the very least, before even using them... to remove the saline from processing, and then being way too moisture retentive for my purposes, anyway. The coco products I had the displeasure of using grew the most colorful and amazing molds I've ever seen in a medium product, which can't be good... and in the end, it turned out to be a complete waste of money and effort on my part. It was my mistake, though... I failed to do my homework on the product, and simply listened to one grower's opinion.

    People are absolutely free to use whatever ingredients they choose in a medium, but they should be aware of the pros and cons of the various items and mixes... so they can make informed choices.

    In all my years of knowing Al and taking his advice, I've never known him to steer anyone down the wrong path, back away from healthy, honest debate, or be a bit rude to anyone. I wouldn't speak up in vindication if I didn't believe very solidly in his abilities, friend or not.

    In agreement with Mike, I, too, shall continue using fir bark until such time as coco coir products can be proven to be as advertised. For now, I simply don't see it... nor has it shown itself to me through use.

    In fact, if anyone wants a half bale, or thereabouts, of cocopeat, they can have it for the price of shipping; it's completely useless to me. Although, I really hate to pawn it off on anyone else and have them experience the same issues I did. I'll leave it at that...

  • silica
    12 years ago
    last modified: 9 years ago

    Meyermike, the phrase "beating a dead horse", is just another way of saying that after a discussion has gone on for a while, that people just begin to repeat themselves. I never intended any disrespect to Al. In fact I believe Al is one of those valued members that are of immense value to a forum. I always respect knowledge. Also I do not think that bark is a bad ingredient for a citrus mixture. In fact the most popular commercial potting soil in the world is 3 parts bark, 1 part concrete sand, and 1 part peat (Plant Production In Containers-II). The gritty mix, bark perlite mix, CHC peat mix, are all good mixtures, but every one of them have drawbacks. There is no 100 percent perfect mix. I like bark, and have used it, it is that I just much prefer coconut chips to bark, for the reasons listed above. I am not alone, as there are many many MANY growers that prefer coconut chips, just as their are growers that prefer bark, or other ingredients. Meyermike, I have no personal care what ingredients you use in your potting soil, use whatever you wish, I don't even know you.

  • meyermike_1micha
    12 years ago
    last modified: 9 years ago

    But Silica, oh but you do know me and have been around here long enough to know what I have done, said, and what my feelings are about CHC, let alone all the time I spend here.:-( We have met before on many occasions and you read here alot too, enough to see who I am for I do know you;-)
    ......................................................
    Posted by silica (My Page) on Thu, Sep 9, 10 at 11:24

    Last Spring I put several of my trees into the 4-1 CHC peat mix. The growth on these trees was absolutely fantastic, far surpassed my other citrus. Actually unbelieveable. Also it is very assureing that a citrus tree growing in a 4-1 CHC mix cannot be damaged from over watering.


    --------------------------------------------------------------------------------
    RE: Updated trees from Coconut Husk Chips to the 5.1.1 mix. Pictu clip this post email this post what is this?
    see most clipped and recent clippings

    Posted by meyermike_1micha 5 (My Page) on Thu, Sep 9, 10 at 12:21

    That is the thing Silica..
    Not that I am not happy for you, in fact proud of you..

    But I have asked so many times for help to be able to grow them as you say you did, and there is rarely anyone to help!
    Where are the pictures of the trees, the close up shots of the CHC mix, the instructions, the fertilizer regimend you use, the step by step instructions, the suppliers, the evidence,the support...ect? Are we at the wrong forum for all the CHC experts and the pictures? Are you able to answer questions about nutritional defficiencies and how to correct them? How many did you loose over the years figuring the stuff out? Did you wash it? How do you keep the salts out? How do you keep the pH perfect?
    There might be many here that are still interested at giving it a try..

    My plants would of died in that stuff by the time anyone could tell me what to do..

    It is nice to know
    ......................................

    I guess sometime forget. We have had many past conversations and at times nice, and at time have not agrred on certain things.

    I think you missed my whole point about thinking about giving it a try and being pushed back even further because people that have used CHC run from healthy debate and still have yet to prove the science behind it and support the evidence so that ones like me can be convinced or have a reason to use them once again or for the first time.

    I am not upset at what was said toward Al, no not at all, in fact he can defend himself, although I must admit I was a bit perturbed because I was not the only one that understood it the way I saw it, but I am dissapointed in the way the conversations end, like what you did, in which it is always the ones that use bark that continue to prove the superiority of it, and the ones that use CHC chips that leave. It sounds fishy to me, that's all.

    If you don't care what I use, then why are you here trying to convince us, me, others that CHC works better and advantages of it over bark?
    I know that people like Al care about what I use, and that is why I continue to follow those that do have a concern for my success and for what is really best for my trees.

    Not harm intended, no hard feelings, for as I said, I also respect you in your crusade to purswade others that CHC is the way to go, and I accept any misunderstandings.

    Have a great weekend nad thanks for your time.

    Thank you Jodi and thank you for your well said post too!

    Mike;-)

  • meyermike_1micha
    12 years ago
    last modified: 9 years ago

    Once again, please excuse my spelling errors since I am hugley under the weather and this computer will not auto spell check for me. I had no time or the energy to go back and correct or preview, but I think most will understand my points and thoughts.

    Sorry and thank you.

    Mike

  • greenman28 NorCal 7b/8a
    12 years ago
    last modified: 9 years ago

    Howdy, folks!

    Silica, did you find any more info on bark?

    I'm thinking that the tannins are responsible for the low pH. What does your research say?


    Josh

  • silica
    12 years ago
    last modified: 9 years ago

    Greenman, when you asked about tannins, I'm not sure if you meant tannins from bark or actually coconut chips. Whatever,the tannins would, of course, be in the form of tannic acid, which is a very weak organic acid with a pH of only approximately 6. Unlike mineral acids, organic acids degrade rather quickly in comparison.

  • greenman28 NorCal 7b/8a
    12 years ago
    last modified: 9 years ago

    We were talking about bark, and you asked me about acids specifically.
    What I'm wondering is why there are reports of such low pH in certain batches of bark.


    Josh

  • silica
    12 years ago
    last modified: 9 years ago

    In reports that you have read, how low of a pH have you heard that were caused by bark in a mix?

  • greenman28 NorCal 7b/8a
    12 years ago
    last modified: 9 years ago

    Some folks tested pH of 3.5 - 4.5, which seemed low.
    I figured that the average would vary from bag to bag and batch to batch,
    but I still Lime my bark to provide Calcium and to increase the pH.


    Josh

  • meyermike_1micha
    12 years ago
    last modified: 9 years ago

    Not only are you being very evasive, but you are of no help to me or many others to even consider the benefits of CHC over bark

    Thanks anyway

    Josh: I and a few others know exactly what you mean and thanks for helping us understand how bark has a much better superiority over CHC and for all the support you have given many over the years on this. Thank God I dumped all my CHC right in the garden after years of disappointment and lack of help.
    'It works for me' and other non-scientific reasonings just does not cut it.

  • silica
    12 years ago
    last modified: 9 years ago

    Josh, because tannic acid is a weak organic acid, it by itself would never cause a pH as low as 3.5, nether would it ever be able to cause a pH of 4.5. pH is logarithmic, therefore a drop from pH 7 down to pH 6 means that pH 6 is 10 times more acid than 7. pH5 is 10 times more acid than 6, or 100 times more acid than 7. PH 4 is 10 times more acid than 5, or 1,000 times mores acid than 7, and a pH of 3 would be 10,000 times more acid than 7. There is absolutely no way that an acid as weak as tannic acid could ever cause such a low pH. Either the person making such a claim is completely wrong, or some other factor in their potting soil is lowering the pH.