Do pumpkins fix nitrogen to the soil?

Discussion in 'Planting, growing, nurturing Plants' started by lovingmygarden, Sep 19, 2009.

  1. lovingmygarden

    lovingmygarden Junior Member

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    My husband was recently told that pumpkins fix nitrogen to the soil, is this true? And if so, are they better than legumes??
     
  2. milifestyle

    milifestyle New Member

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  3. lovingmygarden

    lovingmygarden Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    See,I also thought that ,but my husband reckons he`s right, so I just had to put it out there to check before I say so.
    thanks milifestyle
    anyone else have any thoughts/knowledge on this
     
  4. eco4560

    eco4560 New Member

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    Re: Do pumpkins fix nitrogen to the soil?

    Your hubby is yet to learn the rules obviously.

    Rule 1. The wife is always right.
    Rule 2. When you think the wife is wrong, see rule 1.
     
  5. milifestyle

    milifestyle New Member

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    Re: Do pumpkins fix nitrogen to the soil?


    :lol: :lol: :lol:
     
  6. eco4560

    eco4560 New Member

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    Re: Do pumpkins fix nitrogen to the soil?

    What about hardenbergia (just changing the question)? The flowers look like peas, so does that make it a legume and therefore a nitrogen fixer? They are rather nice....
     
  7. Grahame

    Grahame Senior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    Lovin, I have heard of people using pumpkin as a green manure crop (i.e. dig them in before getting too big and flowering). Perhaps what that is what he was thinking of?

    Grahame
     
  8. Michaelangelica

    Michaelangelica Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    Interesting question.
    i never thought of them as nitrogen fixers, but you made me do some research.
    Pumpkins are Cucurbits (Gourd family)This includes Bitter gourd, bottle gourd, cucumber, ivy gourd, luffa gourd, melons pumpkins, snake gourd, squash, wax gourd
    https://books.google.com/books?id=aE414K ... 20&f=false
    As far as I can see pumpkins don't FIX nirogen; but the plants may CONTAIN nitrogen
    eg
    Chemistry is not my strong suit, so you may like to take this up with a chemistry teacher.
    What happens when you dig nitrogen containing plants into the soil, I don't know. Could be interesting to try

    https://www.uq.edu.au/_School_Science_Le ... html#9.210

    Not quite what you asked but intereting anyway

    https://www.springerlink.com/content/k0v9r114t4754w45/

    Someone trying to sell a wee beastie
    [/quote:1n84ktpy]
    https://www.planthealthcare.com/Ag/Crops ... /Cucurbits

    The lost art of crop rotation
    https://www.ehow.com/how_4480241_guide-r ... arden.html
     
  9. milifestyle

    milifestyle New Member

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    Re: Do pumpkins fix nitrogen to the soil?

    Thats one of the things i like about forums... someone asks a question and if i don't have an answer i research the subject.

    ... not quiet to the depth of you michael... your a walking encyclapedia, your posts are always indepth and well researched.
     
  10. lovingmygarden

    lovingmygarden Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    WOW!!!
    That is food for thought isn`t it. So technically I`m not wrong (hahaha), but in a way he is right LOL.
    I hate not being totally right, oh well I`ll share this one.
    thanks everyone, especially michaelangelica for all that research.
    I guess pumpkins would be a great grren manure crop,because they are so easy to grow (like weeds at my place). I must let my friend knwo too because her pumpkins have taken over her whole garden right now, so she will be pleased to know about this too.
    Thanks again...I`ll have to thinkof another question now won`t I....this is fun.
    Cheers :drinkers:
     
  11. dymonite

    dymonite Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    All plants contain nitrogen. It is part of the 'big three' macronutrients to feed the plant - NPK.

    Nitrogen is an essential component of plant protein and enzymes (for structure and function) and nucleic acids (for reproduction) - the building blocks of all forms of life.

    When a plant dies it does the same thing as when you compost something. It gets broken down by chemical and biological processes that turn it back into nitrogen gas or makes it available to other plants.

    Particularly in the growing phase plants need a lot of nitrogen. Most of them can only draw this from the soil. Eventually the soil gets depleted. It can either be added back as a mineral fertiliser or from organic sources. The traditional sources high in nitrogen are 'green' e.g. mown grass, green crops or animal manures all which ultimately extract the nitrogen from the soil in the first place.

    The only way this source can be truly regenerated into the soil is through the nitrogen cycle. Certain plants i.e. legumes have bacteria on their roots which 'fix' atmospheric nitrogen gas (which is not directly useful for plants) and turn it into a nitrogen compounds which makes it useful for living things.

    All these processes occur concurrently to during this cycle. Without it our diverse plant life (and animal life) would fail.
     
  12. Grahame

    Grahame Senior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    Yep, All plants have it.

    Many of you will of course already know this in greater detail but a simple explanation for those who don't - The benefit of the legumes is that they fix atmospheric nitrogen. That is, they take nitrogen from the air rather than from the ground (where all the other plants take it from). So with non-legumes you can certainly 'cycle' the nitrogen to make it more available in the form of humus. But with the legumes you are actually getting more nitrogen (in theory) into your soil when you dig them in.

    Grahame
     
  13. dymonite

    dymonite Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    Even digging a non-leguminous plant back into the soil adds useful nitrogen. Although the organic form it is not immediately useful to other plants. It need to be broken down by other organisms in the ground to make its nutrient components available. Essentially the organic material acts like a 'slow-release' pellet of mineral fertiliser. Slow release systems are advantageous because simpler nitrogenous breakdown products are rapidly leached away to the subsoil and lost. Humus (the final breakdown product of organic material) can also slow this process down by binding to these chemicals but the process is inevitable unless they are replenished. This is the reason for low soil fertility in the wet tropics. Organic material helps keep all these compounds close to the soil surface so they are available to the plant.

    The breakdown process can be accelerated when making a compost 'tea'. In that situation the chemicals are immediately available to the plant (good for meeting requirements during a rapid growth spurt) but equally can be washed away by rain. 'Tea' is the equivalent of something like 'Thrive'.

    Currently I am using a multi-species cover crop involving a cereal and various legumes - oats, vetch, beans, peas to achieve all of these effects They form a neat little symbiotic relationship.

    The vetch, beans and peas are legumes which fix nitrogen. The oats utilise the nitrogen to set deep roots and add biomass to the soil. The vetch uses the oats as a trellis to climb up.

    If I just used oats then eventually it would deplete the soil of nitrogen and stop growing. As an annual it will eventually die anyway ready for planting.

    The legumes fuel the extensive oat biomass which not only provides a slow release nitrogen source but also improve the structure of the soil. This then adds to the water and nutrient holding capacity of the soil.
     
  14. forest dweller

    forest dweller Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    Pumpkins will not 'fix' nitrogen in the soil.

    Certain plants have a symbiotic relationship with a type of bacteria called Rhizobium. Together they take the inert nitrogen gas (N2) from the air and turn it into nitrogen compounds (e.g. ammonia, nitrates...) that can be used by plants.

    'Peas' (including Acacias) and Casuarinas are amongst the most famous 'nitrogen fixers'.

    BTW - Most plants will contain some amount of nitrogen.
     
  15. Brown grnthumb

    Brown grnthumb Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    I thought pumpkins like dandelion and comfrey were bio-accumulators, though I know for a fact they are used for soil rehabilitation absorbing toxic wastes underground. I believe they were used after Katrina hit N.O. by Guerilla Gardeners
     
  16. Michaelangelica

    Michaelangelica Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    MILLIE
    It helps to be bored, love learning 'STUFF,' and, being a little mad/obsessive.

    I need a job or a girlfriend
     
  17. Noz

    Noz Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    I don't think that pumpkins can fix nitrogen, but the way to investigate would be to carefully examine the roots and see if you can see small nodules on them. what I have heard is that they are excellent composters, so make a pile of manure and straw, grow a pumpkin... and enjoy the compost.
     
  18. purplepear

    purplepear Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    Not sure it's that simple noz. You would have to add the pumpkin vine to the heap or the pumpkin would drag nutrient from the decomposing heap. :wink:

    Dynomite - if you were to add a brassica to your cover crop - say mustard greens - you would round out a great grouping (I think)

    Grahame do you think the majority of nitrogen in the turned in pumpkins would go to feeding the bacteria and other "wee beasties" which work to break down rock into minerals that are available to plants? I think I read that some where - sorry I don't have Micaelangelica's powers of research.
     
  19. Michaelangelica

    Michaelangelica Junior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    I have a friend who has come to gardening v.late. h
    He was VERY proud of his huge (un-sowed?) pumpkin crop.
    Many huge pumpkins.
    Then, his dog ate them.
    :lol: :D :lol: :axe:

    I don't know if the nitrogen in plants would be bio-available to plants.
    So many nutrients depend on bacteria and fungi and other plant-symbiotic "wee beasties"
    It might be best to eat them first;
    then add the nitrogen :butthead: :D
     
  20. Grahame

    Grahame Senior Member

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    Re: Do pumpkins fix nitrogen to the soil?

    I think turned in pumpkins would be great for that purplepear. I'm a big fan of 'green manuring' and I imagine pumpkin plants would be great simply because of the shear mass they can produce quickly. My thoughts are (and this may be proven wrong by science, opinion and greater powers of research than mine) that the more wee beasties in the soil the better - even if you don't actually 'add' nitrogen to system - the quality of the system improves with bio-mass and nutrients become more available to plants. Personally I think one of the real benefits of nitrogen fixing plants is that they can grow where other plants may struggle to find available nitrogen, they make there own. As for how much more nitrogen they bring to the system in real terms, well, like everything else... I imagine it depends.

    The advantages of something like pumpkin seed is it is easy to collect, store and germinate. Those simple things give it instant advantages over something like lucerne. But then again lucerne roots go pretty deep by all accounts and can drag nutrients up from the craggy depths. I guess it just depends on what you are trying to do, what you have available to you and what works.

    It's all good
     

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