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planting citrus in heavy clay soil?

manic_gardener_socal_10a
last year
last modified: last year

I am in 10a. We have very poor draining heavy clay soil here and I am trying to decide how to plant my citrus trees. I have gotten two contradictory opinions about this.

One opinion is don't dig a hole in clay soil at all. You're just asking for trouble. Build a raised mound for the tree using about 9 cubic feet of citrus mix and plant in that.

The other opinion is don't dig a raised mound, because there is no benefit to doing that and it is just going to wash away; instead dig a big hole and mix native soil with citrus mix 50/50.

Obviously the second method would be much cheaper and easier for me, and it is what I'd rather do, if the trees really will thrive like that. but I don't want to do it if the trees' roots are just going to suffocate and the trees are going to stagnate and fail to produce well as a result.

Are there any citrus growers out there who have tried and compared both of these options who could advise me on what will work best?

Comments (69)

  • Howard Martin
    last year

       If you must  dig in the Clay     put some sand in the soil under the trees for some extra drainage  and some lime stone  under the sand and let some nitrogen fixing plants like clover for a ground cover and erosion control 


    Howard

  • tapla (mid-Michigan, USDA z5b-6a)
    last year

    If you must dig a hole in clay to plant trees in the landscape, the transplant should be bare-rooted and the planting soil should be back-filled with the clay soil removed to dig the planting hole. Back-filling planting holes in clay soil with sand or organic materials should avoided because the sand and organic materials will cause all pores in the foreign materials to fill with water (the bathtub effect) for an extended period (until the upper reaches of the water table percolates through the soil to a depth deeper than the bottom of the planting hole).

    Al

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  • Howard Martin
    last year

     Never work clay when it's wet  because it can become like small stones   this I know because of my experience I grew up with the Clay of the great black swamp of Northern Ohio

  • klem1
    last year

    CLAY IS GREAT FOR CREATING POTTERY but not when it's dry.

  • tapla (mid-Michigan, USDA z5b-6a)
    last year
    last modified: last year

    Why did Aristotle believe, like clay, men could mold themselves through their actions?

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    His teacher was Playdough.

    Al

  • gardengal48 (PNW Z8/9)
    last year

    ^^^ As is typical with most gardening YouTube videos, everything she suggests to do before planting the doomed tree is contrary to ALL good horticultural practices!! Digging a large and deep planting hole in a slow draining clay soil and then filling with a different type of imported soil is a recipe for disaster!! All you have created is a giant 'bucket' that holds water.......nothing has been accomplished drainage-wise with this methodology. And the potential for over watering is increased as well, as all that imported soil will give the impression that the water is being absorbed. But It is not. It is just sitting there, hanging around for as long as it takes to penetrate the surrounding clay and eventually dissipate. Not to mention digging a planting hole any deeper than the rootball invites settling.

    You might get away with it for a while but eventually the tree roots are going to hit the perched water table and root rots can and usually do ensue.

    Sorry, but that is really bad advice!!

  • Lemon Lime Orange Zone 6a
    last year

    You know what they say about assumptions. Here are the proof video results two years later. https://youtu.be/MpJu4krDzM8

  • Lemon Lime Orange Zone 6a
    last year

    I subscribed to her channel. She has done an amazing job. If anyone can do any better please upload to your idea book.

  • gardengal48 (PNW Z8/9)
    last year

    No assumptions involved at all!! What I described above has been very thoroughly researched and documented. You will find it repeated all over the web from any science based or educational source. If you simply must amend then you do so over the widest possible area, never individual planting holes.......regardless of how wide or how deep.

    As to the video tree being around 2 years later, the results of this practice are seldom immediate - I did say you could get away with it for a period of time. But it is really just delaying the inevitable. In areas where regular irrigation is a requirement, the outcome is almost always the same regardless of the length of time involved from initial planting.

  • Howard Martin
    last year

     I eat the geese for I'm a Hunter

  • tapla (mid-Michigan, USDA z5b-6a)
    last year
    last modified: last year

    Tana doesn't have a clue, and serves as the perfect example of someone operating at beyond the limits of their knowledge. She got the part right about not adding compost to planting holes, but come on - because the compost eats away at the roots? The REAL answer is because, in clay, amending the planting hole with organic soil amendments or sand creates the bathtub effect and encourages small root systems that eventually produce encircling/ girdling roots.

    Linda Chalker Scott, Ph.D., has a solid reputation built on debunking horticultural myths. HERE is what she says about amending planting holes and the problems that causes. So who should I put my money on, the back yard girl who never quite learned how to say mycorrhizae or the professor with a doctoral degree in horticulture? That's a tough one, but I'm going out on a limb and choosing the good professor whose main claim to fame is laying horticultural myths to rest.

    Al

  • Lemon Lime Orange Zone 6a
    last year

    The good doc is welcome to a bushel of apples next year. I planted 6 apple trees in hard clay soil. The holes were dug deep and wide with pickaxe, crow bar, sledge hammer, shovel and electric drill. The trees have grown beautifully and have never had a minutes trouble in 7 years growing apples. Garden Gal the holes were backfilled with 100% compost. The trees did not sink and have never had an issue with water.







  • Jordan (z7)
    last year

    Ph.Ds mean nothing. Go by science.

  • Silica
    last year

    No such thing as a half a hole. A hole is a hole no matter how large or small.

  • John 9a
    last year
    last modified: last year

    I have experience planting citrus in clay soils and much of the above advice and discussion seems pretty good for the most part....however...

    1. I didn't see a discussion on how fast your tree may grow. It was my experience that growing a tangerine in a raised bed with about 12" of soil above the native level did wonders for growth rate as compared to a Satsuma orange in my native clay. I think the improved aeration could have been key but could have been other variables including a different type tree. For my above ground planter, I hauled in enough river sand to raise the level in a 10'X10' planter 12' above the native level. I tilled the sand into the native clay so I had a mixed media down to around 18-24".

    2. There is an added bonus of a raised bed...if you make it big enough...of having a perimeter to add other plants until your new tree is big enough to need that wider area for its growing root zone. I planted edible ginger, strawberries, aloe, and used it as a starter spot to get other plants started before transplanting to other areas. Here is that planter, now with a different tree (loquat, ginger, and peppers). The tangerine later developed some issues I think were not related to its location.



    3. Lastly, you CAN grow citrus in compact clay soils, even in wet areas....but it will probably grow slowly and may be more susceptible to fungal issues so keep the immediate trunk area clear of grass.

    Here is a Satsuma orange in my native clay soil. There is a shallow roadside ditch on the other side of the fence on the left that may have helped the soil drain. It has done fine here but did grow slowly.



    I just finished planting a new Satsuma and actually signed on to post how I did it. Look for that post if you want to see that. It's a cold-hardy tree so we will see how it does!

  • John D Zn6a PIT Pa
    last year

    I would say that if you dug a bunch of holes, in clay. and amended some and not others that each spring when the water table is high and above the level of the holes that when the water table drops the water in all the holes will empty at about the same time. The amended holes might be a scosh faster. And it won't make any difference to growth. All the plants will grow equally considering only the amount of water and how long it's there.


    From my experience if you drill a lot of post holes that some will fill with water and some won't. It's a random thing. One hole fills the next one doesn't. The next one is a 50-/50 choice. With that happening it's likely that a hole you amended will fill with water and the next one that you never amended won't fill. Another thing I noticed is that you can run a line of posts over to the edge of a 45 degree slope a hundred feed down and the post on the edge of the hill may fill with water.

  • tapla (mid-Michigan, USDA z5b-6a)
    last year

    OK - I think I get it. We should just ignore the laws of physics and what folks like Monrovia and Proven Winners say (because they don't know what they're talking about) and just run with something a wannabe influencer on YouTube (who truly doesn't know what she's talking about) thinks should work. Strong plan, that.

    Bathtub Effect

    Mother Nature is forever patient; and, if there is a flaw in our methodology, eventually she will come down against us on the side of the flaw. For those convinced that amending planting holes dug in clay and back-filled with materials other than the soil removed to make the planting hole (organic matter like potting media, mulch, compost, peat, or sand/ gravel), knock yourself out. My aim is to give pause to those who would otherwise unnecessarily follow a path known and shown to be inherently limiting to their plants.

    Al


  • John 9a
    last year
    last modified: last year

    I think a sign of intelligence is to recognize what has been done and understand why some things do and don't work but also to recognize hardly any rule always applies to every situation.

    I have had some tell me I needed to get the grass out from under my citrus. It's a no-brainer that the grass steals some nutrients and I guess I would if it didn't take herbicides to reasonably accomplish that. I take a happy medium which is hand pulling enough grass to keep from having a damp area around the trunk. I can get fruit grown with herbicides at the store. I also suspect the grass is providing habitat for some bugs and such that are in fact adding some fertilizer, and I suspect the grass provides some insulating benefit during the winter. As far as the bathtub effect goes, we already know we aren't following the citrus label which, in every case I have seen, says plant in well-drained loamy soil. If we don't have that, then we try to improvise. I just wonder how much wetter a huge hole with sand in it is than a huge hole with native clay in it. Arguably, the sand will dry out quicker than the clay if one begins with both equally saturated.


    Along these lines, I have heavy clay and I have been quite successful with adding some kind of organic material to the backfill. My goal is to include some material that will keep the clay I put back in the hole from being a compact glob that will be quite lacking in aeration pores and difficult for new roots to penetrate. Adding organic matter provides some long-term organics for nutrients, leaves spaces for roots to enter as it degrades, and hopefully provides some porous material for aeration. It probably doesn't work in all soils and maybe for some reason I'm not doing the best thing.....but it does grow some fine citrus in soil not described by the lable.

  • Ken B Zone 7
    last year

    You just need to do what works for you. Different things work in different environments and environments vary even in backyards in the same town. On this site we are dealing with people from all over the country, even the world. What works in my backyard wont necessarily work in yours.

  • Silica
    last year
    last modified: last year

    Although I often disagree with Tapia, on his issues he is correct. When planting a citrus tree it is ALWAYS best to refill the hole only with the dirt that was removed while digging.

  • tapla (mid-Michigan, USDA z5b-6a)
    last year
    last modified: last year

    When making the decision re how to plant in clay, research definitely shows reliable sources suggest a number of ways to ameliorate the bathtub effect, so it can't/ shouldn't be scoffed at as though it doesn't matter. Remediation efforts include planting on a mound or raised bed above the existing grade, creating artificial drainage by using techniques like french drains, sump holes, ditches or tiling on grades, and avoiding amendment of planting holes with organic media. Even in non clay soils, conventional wisdom in all slow-to-drain soils advises not to amend planting holes with organic matter or material coarser than native soils because of the limitations inherent in that practice. Not only does it invite issues associated with saturation within the planting hole, it inhibits roots from moving out into soil outside of the original planting hole, especially if the planting technique consists of little more than separating the root soil mass from a nursery can and dropping it into a planting hole, or following the same course with a B&B tree.

    Some people are unaware enough that they need to be warned against using an electric hair dryer in the bathtub or ironing their clothes while wearing them. Often, issues associated with poorly prepared planting holes are not made conspicuously manifest for several years after the causal event. With the time lapse between the cause and when the effect becomes conspicuous, few growers will make an accurate cause/ effect connection and will consider poor performance or failure to be the result of an imaginary cause, or simply file the failure under the heading of 'idiopathic' and forget it, moving on and learning nothing from the potential lesson. So while it's true we can evade reality, we can't evade the consequences of evading reality.

    As far as what serves as a sign of intelligence, avoiding practices known to increase the probability of failure or poor results is certainly something that passes the 'reasonable man test'; whereas, putting practices in play that unnecessarily multiply the potential for future problems does not. Is it reasonable to avoid changing the oil in our vehicles because someone anecdotally suggests it really isn't an absolute requirement? It's true it isn't absolutely required, and it's true that for a while the strategy will likely be free of consequences, but the same can be said re poorly prepared planting holes.

    Al

  • klem1
    last year

    Are you talking about choosing a life mate or planting a tree?

  • I_Grow_Almost_Everything
    last year

    i also have some serious heavy clay here too. When I planted my citrus i did so above the soil grade and just mulched it the rest of the way with pine shavings. They are doing great and I'm sure if you just plant it above the soil line and mulch it with woodchips or shavings you'll be okay. The soil underneath will eventually soften but keep adding mulch as it breaks down to keep the roots happy and improve the soil structure

  • I_Grow_Almost_Everything
    last year

    I mulched them in a ring shape and added mycorrhizae in the soil to spur it along. When I pull the mulch back i find mycelium everywhere so I guess it did work well.

  • tapla (mid-Michigan, USDA z5b-6a)
    last year
    last modified: last year

    Because of its minute particle size, clay's capillary 'pull' is much greater than that of mulch, container media, peat, sand, and other fine or organic amendments which might be made to build a mound. Mounding works so well in clay soils because (unless the clay is 100% saturated to the point where the top of the soil surface has puddled or is glistening due to saturation) clay's greater capillarity easily pulls water from whatever material (other than clay) the mound is comprised of. If/ when the the soil beneath the mound is saturated, and since the first part of clay soil to dry is its upper surface, water beneath the mound is free to disperse/ diffuse laterally across the upper surface of the soil surrounding the mound where it is easily lost to the surrounding air; 'easily' being a term used relative to the rate at which water residing below the upper soil surface, where there is very little gas exchange, evaporates.

    Al

  • Lemon Lime Orange Zone 6a
    last year

    There are 19,000 soil types in the USA and many sub-variations of "clay". Your broad language and over-generalization that one backyard is the same as another are very misleading. From your idea book, it should grow on everyone from Home Depot to the tiny containers you plant in with 5-1-1 you have zero first-hand experience planting trees, digging holes, back-filling, growing citrus, or amending clay. You could back-fill your big box store plants that come planted in peat moss with a Popsicle stick. There is not a single tree, citrus, or material size hole dug in your idea book. Your most complicated project seems to be tomatoes. Rather than spam us with grade-1 science experiments why not get your hands dirty and gain some first-hand experience? Would love to see you overwinter your first citrus tree. People that are highly successful in the garden are people that have learned lessons from failure. People who are afraid to try something new or dig a hole for fear of failure learn nothing.

  • gardengal48 (PNW Z8/9)
    last year
    last modified: last year

    ^^^ WOW!! What a litany of ill-founded assumptions! First, to assume any individual's gardening experience is going to be reflected fully in their Houzz 'idea books' is preposterous. Many posters do not even create idea books and they were never conceived to reflect that sort of experience to begin with. You cannot possibly know anyone's gardening expertise from that source alone so you have NO conceivable idea if the poster in question has " zero first-hand experience planting trees, digging holes, back-filling, growing citrus, or amending clay. "

    Science is science - and almost impossible to refute - and there is nothing remotely "grade 1" about soil science and the physics of water movement through soil. That is college level technology. And based on the lack of any scientific support provided for your planting methods, I'd venture you have had minimal participation in or an understanding of these principles yourself. There is a serious lack of logic displayed in statements that boil down to nothing more than "I've done it, it worked, so it must be right". Naiveté in the extreme!!

    Finally, I find it more than a little self-serving for a relatively recent newcomer to the forums with nothing to substantiate their gardening expertise to make derogatory and slightly offensive comments about a forum member that is perhaps the most knowledgeable participant we are lucky to have here on all aspects of soil science - and has been for many, many years. Al has probably forgotten more about soils and proper planting methodology than you will ever know!

    It is you that is spamming, Lemon Lime Orange Zone 6a. And it is unwelcome and unnecessary.

  • tapla (mid-Michigan, USDA z5b-6a)
    last year
    last modified: last year

    I'd like to say that, in general, emotion is an irrational judge, and anger is a poor substitute for rational analysis. The power of a diatribe is great for gaining attention, but the power of reason is what carries the day in a debate. When compelled to turn to ad hominem attacks, the debate is already lost.

    "People that are highly successful in the garden are people that have learned lessons from failure." I would like to make an observation about learning. Getting bit on the butt by our mistakes/ failures is a painfully slow way to learn. I think we can agree that don't drink and drive, don't do unhealthy things, don't skydive w/o a parachute, are all examples of situations we'd be better served by learning what the potential outcome might be before we act. Much better is to learn first, then use our experience (practical application) to verify what we already know. By avoiding the consequences of our errors, we'll leave the trial and error crowd standing in our slipstream, still learning lessons from failures. Of course we would need to be willing to give up first hand knowledge of the consequences of driving while impaired and skydiving w/o a parachute, but I think most would be willing to live with missing out on that experience.

    And, it hasn't yet been considered that when trial and error learning is being employed, there is a general lack of knowledge in play (otherwise .... the trial and error method wouldn't be necessary and would be discarded). W/o a basic working knowledge of what we are actually doing, cause: effect relationships are much more difficult and unlikely. This means we are bound to keep recommitting our errors until we are willing to commit to learning how to avoid the consequences of our errors. Does anyone think it's not better to follow the path more likely to eliminate the 'error' part from 'trial and error' and simply use the 'trial' half of the equation to verify what we've learned? Change might not always bring growth, but there is no growth without change.

    Al

  • Ken B Zone 7
    last year

    Another thread down the drain because of the pissing contest between these two. It's really getting old

  • gardengal48 (PNW Z8/9)
    last year

    " the pissing contest between these two "

    Oh, there's no contest at all here! One party speaks from a background of facts and science and decades of experience while the second just throws out random, unsupportable statements and a lot of assumptions. That's like a contest between a slingshot and a rocket launcher!!

  • Lemon Lime Orange Zone 6a
    last year

    Garden Gal and Al got called out for rude comments about a YouTube Channel called Passion for plants by Hannah which has 9.45K subscribers. Rather than recant their snide comments when shown a video of the before and after results two years later they have doubled down on the mean comments.


  • John 9a
    last year

    Hmmm, perhaps I should keep my thoughts to myself but I'm not going to call anyone out or be rude or judgmental. I will say that, generally, there are ways to share thoughts and opinions and facts without being insulting. That goes for all of us, certainly me included.


    I used to be a regular here and learned a lot. I was always impressed with the knowledgeable people we had/have and lots shared their perspectives and experience. I had to keep in mind though that we have a menagerie of problems and priorities depending on if we grow in containers, in-ground, nasty winters, no winters, wet climate, dry climate....lots more...herbicides or organic. I listened and learned but ultimately practiced what worked in my area. Oddly enough, it wasn't how deep I planted my trees, whether I supplemented with organics, or whether I used 13-13-13, Roundup, or staked my trees too long that killed most of them. It was that crummy cold snap year before last that hurt the most.


    Smile folks. This is supposed to be a fun hobby!

  • Howard Martin
    last year

       I don't know if you  or anyone can tell me how many Meyer lemon varieties are there

  • gardengal48 (PNW Z8/9)
    last year

    ^^^ Is this a trick question??

  • poncirusguy6b452xx
    last year

    No it is not a trick question. There is only 1 variety of Meyer lemon.

  • annpat
    last year

    Lemon, Lime, Orange, aren't you worried about all that compost eating your tree roots?

    Yeah, I wouldn't be either, because Hannah made that up. I'm sure Hannah's a nice girl just trying to make a living as an influencer, but she should have picked a different subject or acknowledged her inexperience.


    If you actually planted your apple trees in 100% compost 7 years ago, I'm stunnned they aren't dead yet. Maybe there was a whole bunch of soil in your compost? There's a lot of degrading that takes place before compost becomes humus. After 7 years, I would expect those apple trees to be sitting in fairly depressed clay bowls.


    Idea book? I've been posting here for 24 years and I didn't know we were supposed to be keeping an ideabook. I feel like a fool.




  • annpat
    last year
    last modified: last year

    "Rather than recant their snide comments when shown a video of the before and after results two years later they have doubled down on the mean comments."

    Lemon---that tree that you claim shows two years of astonishing growth? The tree she planted in your first video is a miniature Meyer lemon. The second tree is a Tangelo orange---a full-sized tree. They aren't the same tree.

  • Howard Martin
    last year

     My knowledge is small when it comes to citrus  that is why I came to this fourm in the first place

  • Howard Martin
    last year

      I use some science in my discussion and I'm no expert


    HOWARD

  • Howard Martin
    last year

     I have a serious question why is there only one variety of Meyer lemon when some say that they are sweet some say they don't taste too good saying that there is only one variety doesn't make much logical sense

  • klem1
    last year

    Howard the answer you are looking for will be found in the science of humans not in the science of fruits. Some like beer and others say it smells like pi$$.

  • Howard Martin
    last year

     Heavy Clay I know a little bit about because I grew up in the Clay  rich of north western Ohio and there used to be the great black swamp

  • Howard Martin
    last year

     And the reason why some Meyer lemons the science  Is  there directson of what side comes through most the mandarin orange  or the blend or the lemon  this is why  some Meyer lemons taste different from different trees

  • tapla (mid-Michigan, USDA z5b-6a)
    last year
    last modified: last year

    @Howard Martin That a plant fits the accepted and recognized description for its given species shouldn't be taken to mean that all plants included in the species are identical. There is a great deal of genetic diversity within any given species, which would have influence over many factors, taste, color, size, shape, etc.. In addition to genetics, cultural conditions (and provenance - where the plant originally came from) can have a significant impact on taste. Among the influencing factors are soil pH, soil structure/ type, soil chemistry, nutrient availability, light levels, temperature, age of the plant, moisture availability/ water quality ..... and more, all have their influence on flavor.

    Al

  • CA Kate z9
    last year
    last modified: last year

    All this discussion aside, there are several different soils that are called ”clay”.

    When living in Ohio we had a strip of ”clay” in our yard that was totally water resistent, would grow nothing, and that you could digout and throw a pot. ( I was a Potter at one point in my life, so i know that kind of “clay”.)

    Then there is ”clay” soil that is totally different, but still called that. With a lot of amending it becomes really good garden soil.

    Then there is California (SW) Adobe soil, also thought of as ”clay”. I have three citrus trees planted in unammended holes and I have to have the gardeners cut-back the lemon and lime twice a year or they’d be too tall to harvest. Needless to say, they are doing fine.

    So, to the original poster: define the “clay” to which you’re referring.

    And, take a sample to your local University AG Dept. or local Master Gardeners for some local/good advice.