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Tomato Root Length - Soil

hdogg
15 years ago

Hi-

I planted 3 types of tomatoes, big boy, goliath, and celebrity....

what is the typical root length, how deep does the soil need to be loose? what types of fertlizer? should i mix it with the dirt?

Comments (31)

  • carolyn137
    15 years ago
    last modified: 9 years ago

    what is the typical root length, how deep does the soil need to be loose? what types of fertlizer? should i mix it with the dirt?

    *****

    Root length and how far down the soil needs to be loose are really two separate issues and I think that will become clear once you read the link I've posted below.

    As to fertilizers, the first decision you have to make is whether you prefer an organic or inorganic type fertilizer and then folks can better answer you.

    Some will reply that the first thing is to improve the soil every year so that no fertilizing is needed, but I wouldn't say that all "improved" soils are able to furnish everything the plants needs in the way of nutrients.

    But improvinmg the soil is always a goal if one has the time to do so.

    So, will it be organic or inorganic fertilizers you're looking for?

    Carolyn

    Here is a link that might be useful: tomato root length

  • hdogg
    Original Author
    15 years ago
    last modified: 9 years ago

    awesome article!!! inorganic fertilizers -- the kind you buy from the store.. pellets/miracle grow

  • oldroser
    15 years ago
    last modified: 9 years ago

    I'm using 10-10-10 but I have light, well drained soil and the nitrogen will wash out fast after the plants get started. In more retentive soils I'd go with 5-10-5.

  • coolbythecoast
    15 years ago
    last modified: 9 years ago

    Carolyn, thanks for the article, but now I know that I am not as smart as I think I am. After a couple of quick readings I still an not sure concerning the relationship of root length and how far down the soil needs to be loose.

    From that article:
    "Deeper plowing than usual aids in securing a more deeply penetrating root system. Plants with deeply penetrating roots are most assured of an even moisture supply"

    I assume that plowing is usually relatively deep and deeper than usual must be really deep.

    From Fig 17 there is evidence that the majority of the roots were located in the first foot, but with many roots several feet down.

    You wrote:
    "Root length and how far down the soil needs to be loose are really two separate issues and I think that will become clear once you read the link I've posted below."

    Sorry for being so thick, but what is your take on why loose soil depth and root length are separate issues? It would seem from the quote above that the article encourages deep plowing to accommodate deep roots.

    I do note that the roots spread long and wide from the plant, therefore the soil should be made loose in a very wide circle around the plant. Charles Wilber (tomato record holder) goes a little further than most in that respect. He lays 8 flakes of hay around the tomato to keep the soil moist to the very surface and adds compost under the hay, encouraging the tomato roots to spread across the top of the moist soil.

    Thanking you in advance for your input,
    Gary

  • carolyn137
    15 years ago
    last modified: 9 years ago

    You wrote:
    "Root length and how far down the soil needs to be loose are really two separate issues and I think that will become clear once you read the link I've posted below."

    Sorry for being so thick, but what is your take on why loose soil depth and root length are separate issues? It would seem from the quote above that the article encourages deep plowing to accommodate deep roots

    *****

    Note that the article was published in 1927. Most of the basic traits of the tomato life cycle were intensely studied in the 20's and 30's.

    Plowing was different back then in terms of how deeply that could be done.

    But the reason I said what I did is b'c you saw that mature tomato plants could have roots down to 3-4 ft and no one is going to dig a hole that deep to plant a tomato plant. YOu also saw how far the roots spread out laterally and I can't think of anyone who would also dig down and loosen soil out that far.

    Modern plows go down about two feet and that's good enough for fibrous rooted plants that result from transplanting.

    Make sense? ( smile)

    Carolyn

  • spiced_ham
    15 years ago
    last modified: 9 years ago

    If you plan to grow on a residential lot you might want to dig a test hole a couple of feet deep just to see what the soil stratification is like. Here, the deep clay soil excavated for the basement was spread over the lot and then covered with topsoil and sodded so that we have about 6-8 inches of good dirt over top of several inches to a foot of clay/rock, which is over a couple of feet of good topsoil. If the clay layer is not penetrated and broken up with deep digging at least once the roots can't get down to the soil beneath and need a lot of water in the summer.


    You might be interested in the doing a search for the "double digging" method of garden prep. If you do decide to hand dig a double dug garden I suggest, rather than digging a series of parallel row trenches and hauling the pile of dirt from the first strip to the far end of the plot to fill the last strip, dig a single trench in a U or W etc. so that the end finishes up near to the beginning where you have piled the dirt.

    good luck with your plants

  • zeligbass
    9 years ago
    last modified: 9 years ago

    Hi.
    Well, reviving a posted I googled from 2008...
    In the article that Carylon linked to (first reply above), the first section after the opening mentions that optimally the tomato plant would have a nice strong taproot but since we start seeds a few weeks before the garden is ready to receive the plants, we settle for a fibrous root system, because the taproot has bent sideways within the limited space of the seedling environment.
    The article states: "A desirable plant for setting in the field is 6 to 8 or even 10 to 12 inches tall..." But from what I understand, this is only because we wish to start seeds when outside it is too cold to plant. My question is, if I start late, would it be correct to start seeds in a 4" deep container and transplant to the garden when the plant is only 1.5" (very different from the "desirable 12" quoted above) and hopefully, still have the taproot undisturbed (transplant before it hits the bottom and is diverted sideways) and hence, have a plant with a totally different root system than you would otherwise expect, based on its deep strong taproot rather than the fibrous root system...?
    Thanks. Ilan.

  • seysonn
    9 years ago
    last modified: 9 years ago

    In my opinion, for all practical intent and purposes a depth of about 12" -15" is sufficient, provided that depth is well amended has right moisture retention and drainage properties.This is assuming the ground underneath is not solid rock or concrete or 100% clay.
    There is a natural law called " The Path of Least Resistance". When roots cannot grow down vertically, they will grow laterally/side way . That is often the case in a backyard home garden, with a growing season of about 4 to 5 months in length. Maybe, if one has a growing season longer than 6 months, plant may benefit from deeper fertile soil. The same principle can apply to container size, as it relates to root bounding: Longer season ( 6+ mos)>> deeper soil and bigger container.

  • zeligbass
    9 years ago
    last modified: 9 years ago

    Thanks.
    Further down in the article I later found that indeed transplanting reduces yield: "Those not transplanted yielded more than those once transplanted, while those twice transplanted yielded least..." So seeding directly into the garden and never transplanting is best practice...??? (we have no frost where I live. I think I can seed into the garden in the beginning of March). On the other hand, if seeding straight into the garden, you will miss out on... quote from the article: "Setting the plants several inches deeper in the soil than they were in the seed bed or container is beneficial since the plant will stand up better and the new roots will develop along the stem". I guess it will be hard to get an answer as I assume you all seed in containers and transplant...
    Thanks.
    Ilan.

  • slowjane CA/ Sunset 21
    9 years ago
    last modified: 9 years ago

    wow this book/article is blowing my mind. ! thanks for posting carolyn127! ;)

  • carolyn137
    9 years ago
    last modified: 9 years ago

    I didn't go back and read the link I gave above, but have linked to it many times here and elsewhere and have read itmany times. And again,note the date of the article for the reasons I gave above, methods were very different back then but the reason I do link to it is to show how deep roots can go and also the difference between tap root and fibrous root structures.

    Basically what it's sayingis that it' sbetter to set out plants that have a fibrous root structure rather than a tap root structure like carrots and beets have.

    So it means transplanting small seedling just ONCE to something else,in my case that would be 6 packs with cells about 1 1/2 inches and I grow theplants in these same 6-packs until about 6 to 9 inches tall, and then set them out after hardening off.

    Yes, the roots are rootbound and that's exactly what I want.

    Only if you direct seed inground or in some other permanent place, without transplanting, do you get a taproot structure.

    The reason that almost everyone I know wants a fibrous root structure is b'c there are many more rootlets that can take up water and nutrients.

    I have never potted up seedlings to larger and larger containers since to me it just doesnt make sense.

    Someone above wanted to put inground 1 1/2 inch seedlings/ That's the size I take from my seed containers to transplant to the 6 packs, and I would never directly try to harden them off and set outside at such a small size.

    Carolyn

  • zeligbass
    9 years ago
    last modified: 9 years ago

    "So it means transplanting small seedling just ONCE to something else,in my case that would be 6 packs with cells about 1 1/2 inches"

    Why not set the seeds straight into these? I am just starting now. I happened to have a few trays with narrow cells 4" deep and trays with the tiny cells (3/4" side to side and 1.5" deep...???) The seeds in the large cells had 90% germination and developed well. Those in the tiny cells had 50% germination and there growth got stuck on a very small size.

    Ilan

  • carolyn137
    9 years ago
    last modified: 9 years ago

    Why not set the seeds straight into these? I am just starting now. I happened to have a few trays with narrow cells 4" deep and trays with the tiny cells (3/4" side to side and 1.5" deep...???) The seeds in the large cells had 90% germination and developed well. Those in the tiny cells had 50% germination and there growth got stuck on a very small size.

    &&&&&

    Quite a few folks do what you did, but they put seeds, several, of one variety in each cell, and it's called dense sowing and works well for many.

    But for many years I was growing many hundreds of plants and varieties and used 20 row professional inserts and I could get about 5 seeds/variety and about 4 different varieties in a row, so with good germination, several seedlings for about 4 X 20 = 80 different varieties/insert, and that worked best for me at that time.

    Before that I was using 8 X 8 inch Permanest trays, but it took too many of those to get the numbers of seedlings I needed.

    So different strokes for different folks, according to their needs. ( smile)

    Carolyn

  • digdirt2
    9 years ago
    last modified: 9 years ago

    As Carolyn mentioned already we have discussed this article in great length many time over the past years here and it is a rather mind-opening article to say the least.

    But if by saying "Why not set the seeds straight into these?" you mean seeding and growing them there until the size for the garden and only then transplanting them, then you would miss the interim staged transplanting benefits of the fibrous root development. They are then much better able to survive the stresses of hardening off and adjusting to the outdoors.

    I do dense sowing as I also grow transplants for sales so individual cells will usually get anywhere from 20-20 seeds in each. Once the cotyledons develop each is transplanted to its own cell to grow. The transplanting is what triggers the fibrous root development.

    Many of my plants are then transplanted yet again into 4" or 6" pots for individual sales but that step isn't necessary (recommended but not required) for most home growers - unless they start their plants far too early. In that case multiple transplantings may be needed just to keep the plants healthy until they can go to the garden.

    Dave

    PS" if you want to read more of the earlier discussions try the terms 'potting up' and 'staged transplanting' in the search bar here.

    This post was edited by digdirt on Sun, Jun 1, 14 at 21:38

  • zeligbass
    9 years ago
    last modified: 9 years ago

    I certainly will like to further read on these matters. You guys have just opened my eyes to many things I wasn't aware of. For the life of me I thought I gathered from the article that taproots were preferable over fibrous, only not commonly practiced for technical reasons. Communities of helpful folk are good... I'll read the articles and google further.

    Thanks.

    Ilan.

  • 2ajsmama
    9 years ago
    last modified: 9 years ago

    Dave - did you mean to say that potting up again (after separating dense seedlings into individual cells) was UNnecessary for most home gardeners?

    Carolyn just pots up once - says she wants the plants rootbound. Though the article says that those transplanted only once yielded earlier, didn't it also say that those transplanted multiple times were healthier, stronger?

    "The potted plants, which were no larger than the plants in the flats but had a better root system, grew much faster than the others. They came into bearing early in the season when the price was high and gave by far the greatest financial returns, although the plants from the greenhouse bench and flats gave practically the same total yields."

    Interesting - I just started growing from seed a few years ago, was taught by someone whose family had been in nursery business for generations, he had extensive vegetable garden and he started multiple seeds per cell but then snipped all but 1, later potted up to 4" plastic but left the plant there - some of his plants were over 2ft tall when he transplanted them.

    When I started reading more here I realized that wasn't optimal, but the following year when I started them in my house (the first ones came home from the greenhouse with aphids), I did the same, but tried to transplant when they were less than a foot tall.

    Then I found Craig LeHoullier's dense seeding technique (I felt bad snipping of seedlings!) and would prick each seedling out and transfer to individual cells. Some made it, some didn't, but at least I didn't "waste" seed/healthy plants. Still potted up to 4" pots and sold the extras. Some got put in even larger pots if they didn't sell before they got a foot tall, or seemed to be rootbound. But ALL, even the ones I was planting for myself, got taken out of cells and into pots, unless I ran out of pots. I did transplant some straight from 6-packs into the ground last year b/c I ran out of pots, but I didn't notice a difference in growth - of course last June was so cool and wet that nothing really was growing well.

    This year I ran out of pots again - all the seeds I started April 6 (mostly determinates) and some March 29 (mostly indeterminates) are still in individual cells, as are all the peppers I started earlier in March. The peppers are definitely getting rootbound. I've been stressing over not having enough small pots to transfer them into. The March tomatoes are all hardened off now, and will be planted over the next couple of days now that the cold nights are over (hopefully) for a few months.

    Should I not bother potting up the April starts at all, just harden off in the 6-packs as Carolyn does? Most of them look pretty healthy, but some as getting leggy and have some stress, yellowing/shriveling bottom leaves.

    What about the rootbound peppers - put them in the pots I have the March tomatoes in now, before hardening off next week? Again, a lot of the peppers are looking a bit yellow though I have tried to water with diluted fish emulsion. Some are even getting leggy. I realize peppers and tomatoes are slightly different, peppers don't form adventitious roots quite as easily as tomatoes, but do they benefit from being transplanted from rootbound cells (potted up to individual cells 2 months ago) or do they need a larger root system before transplant?

    Sorry that got a little OT, just figured if we were talking about fibrous root systems and when to transplant that I'd ask about peppers as well as tomatoes.

    This post was edited by ajsmama on Sun, Jun 1, 14 at 7:34

  • seysonn
    9 years ago
    last modified: 9 years ago

    "...They came into bearing early in the season when the price was high and gave by far the greatest financial returns,...."
    %%%%%

    It seems that this study is geared toward commercial growing, as it talks about economics and profitability.

  • digdirt2
    9 years ago
    last modified: 9 years ago

    It seems that this study is geared toward commercial growing, as it talks about economics and profitability.

    The majority of the research done is directed at or funded by the commercial industry be that tomatoes or kumquats. That is to be expected.

    But the focus of the study (studies) is about growing tomatoes. That they may also have commercial growers interests doesn't make the growing info any less helpful or applicable to home growers.

    Dave - did you mean to say that potting up again (after separating dense seedlings into individual cells) was UNnecessary for most home gardeners?

    With all the qualifications I added (proper starting times, stage of growth at transplanting, size of containers used), yes. The goal is to get them to put up at least once. More often is better IMO but when properly grown, the seedlings don't require it.

    So many think the 6 pack of plants they buy at the nursery/big box store were grown in those six-packs from seed. So they generalize from that faulty assumption that it must be ok to stick their seed into a 4" pot (or even bigger) and just leave it there until time to go to the garden.

    That isn't true. In most cases the nursery grown plants have been transplanted 2x. Once at cotyledon stage from the germination trays or plug flats to small individual cells and then again at 2nd true leaf stage into those cell packs to get ready for sales. If they have to stay in the average 6 cell pack for more than 7-10 days, they are transplanted again into 4-6" pots.

    Yes I know Carolyn likes root bound plants but generally I don't as it is a source of stress. But there are 'small r' root bound plants that are fine. And then there are 'big R' Root Bound plants and it is those that need to be avoided when possible.

    For those who start their plants way too early as many do or when garden transplanting is delayed for some reason beyond their control then they may need to transplant several times just to keep the plants healthy or root cuttings from them.

    Hope that clarifies.

    Dave

  • 2ajsmama
    9 years ago
    last modified: 9 years ago

    Thank you Dave - I did think I knew what you meant but thought I'd mention the typo so you could go back and edit.

    Well, my plants have been in individual cells for much longer than 7-10 days so I guess I should pot up. Didn't get any planted today due to picking up kids from various activities and a family birthday party, but will be planting most out soon, will pot up others and give them a day to recover before starting to harden them off.

    I guess my first priority should be those rootbound peppers. Thanks.

  • ncrealestateguy
    9 years ago
    last modified: 9 years ago

    Tomato and pepper plants are put in the ground directly from the six pack stage by the millions every year across the Country with good results.
    I don't see the difference between planting a root bound six packer into the ground or planting it into a bigger pot.
    And, why don't my garden volunteers have a large tap root?

  • fireduck
    9 years ago
    last modified: 9 years ago

    Sey has hit the nail on the head as far as I know..."path of least resistance". I have learned over the last 29 years with my small farm...thick clay soil is really tough to get my trees to grab the native soil. Breaking up the soil or to a lesser extent...chemicals like gypsum sure does make a difference. Two years ago (just for fun) I planted a tomato plant in a 3 foot long pipe (12" diam. and potting mix). At the end of the season I found the roots all over the bottom of that pipe!

  • 2ajsmama
    9 years ago
    last modified: 9 years ago

    I don't know if the plants have been in the 6-packs you buy at BBS for 2 months like my peppers have. I'm really afraid to harden them off as rootbound as they are. I'd like to get them in a bit more soil first. This afternoon's project (while it's in the 80's, sunny and humid outside).

  • digdirt2
    9 years ago
    last modified: 9 years ago

    And, why don't my garden volunteers have a large tap root?

    Do you leave them to grow where they sprout? If so then they will have a very long tap root in addition to the fibrous roots they develop. They will just have less fibrous roots than if you transplant them from where they sprout to another location. It is the act of moving them, of transplanting them, that triggers the changes in root development.

    I don't see the difference between planting a root bound six packer into the ground or planting it into a bigger pot.

    I'm not clear on why you think anyone is advocating doing that. The goal is to avoid overly root bound plants. To do that you have to transplant them into something be that garden when possible or a bigger pot.

    Dave

  • drmbear Cherry
    9 years ago
    last modified: 9 years ago

    For years I've been using a post hole digger to plant my tomatoes. I dig very deep, mix compost with some of the removed soil in the very bottom, pinch all the leaves/branches off the sides of the stem except the top few leaves, and plant it as deep as possible. Often, even those top few leaves are even planted in a depression that will be filled in around the plant later as it grows upward. The main stems of my healthiest plants are often 2 to 3-inches across at the base - I've had people tell me they've seen nothing like it. Roots will grow off of that entire planted stem, and I've had so many roots at such a depth they can't be pulled up at the end of season without some digging. Here at my new house only a year, it will take me another year or so to get all the surface soil improved to where I want it, but I still plant my tomatoes this way with at least a deep hole improved for my tomatoes.

  • johns.coastal.patio
    9 years ago
    last modified: 9 years ago

    I've been thinking that in the right soil I'd try that, drmbear. Ever since I saw the video of a guy digging a well with a hand auger. Good to hear that it worked so well for you.

    (Just think, with an auger you could go even deeper!)

  • seysonn
    9 years ago
    last modified: 9 years ago

    No doubt in my mind that big deep root is good , for trees and perennial but I personally doubt its benefit as being substantial for an annual that has just 4 to 5 months to live. That is true about tomato plants to most of us in zone 8 and lower. Tomato plant being a perennial, would dig in and grow big root system, huge foliage in anticipation of a perennial life. That is why it keeps growing, budding flowering until the cold stop and/or kills it.

  • drmbear Cherry
    9 years ago
    last modified: 9 years ago

    I really don't need an auger - I don't let my tomato starts get so leggy that they need a terribly deep hole. The post hole digger just allows me to completely remove the soil in the hole fairly easily so I can mix the removed soil with compost and make sure the plant is put in as deep as is reasonable. It's just amazing to me that when I plant with only the top couple of leaves are showing, I can end up with visible significant growth once they take off in the week or two ahead. Mine are in that rapid growth phase right now - got them in somewhat late because of the late freezes.

  • johns.coastal.patio
    9 years ago
    last modified: 9 years ago

    I know you don't need an auger drmbear (no one does) but it would be fun (for my warped sense of gardening) to fill compost down 3-4 feet, leading the roots down.

    I think you have a good practical system, rather than my crazy dream.

  • cold_weather_is_evil
    9 years ago
    last modified: 9 years ago

    >> I know you don't need an auger ... but it would be fun ... to fill compost down 3-4 feet, leading the roots down.

    I think using the Acme Tomato System (below) is proof you need better lights.

  • johns.coastal.patio
    9 years ago
    last modified: 9 years ago

    hahahahha

  • plaidbird
    9 years ago
    last modified: 9 years ago

    Hummm ... and in the off season that would be perfect for dandelion removal.

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