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Cost-effective (and green) monitoring of plant water

  1. Feb 21, 2016 #1
    What do you think is the ultimate way to oversee plant nutrient water composition - say you need to check the nutrient levels from a natural water source for all the essentials a handful of times a year? Full profile: N, P, K, Ca, S, Mg, B, Cl, Mn, Fe, Zn, Cu, Mo, Ni.

    Preferred method would be to use the least amount of disposables, and naturally, to be able to get it done relatively easily.

    Cost effectiveness in this case means an investment of anywhere between 1-10k €.
  2. jcsd
  3. Feb 21, 2016 #2
    It depends on the variety of plant you want to grow and you don't need a full or a comprehensive test(all minerals and elements) just for the sake--unless, you test the water for contaminants --wherein a comprehensive coverage of pollutants might be tested.

    Stick with the basic of life. Plant do need(aside from sunlight and carbon dioxide) first, a good organic food, second- fertilizer(NPK) and third-minerals.

    This guy has sense and may help with your problem. He does actual testing by growing.
  4. Feb 21, 2016 #3
    I live in the vicinity of lakewater and I've been pondering about making a little (warm) greenhouse in which I could grow some veggies and fruits for food all year round, or at least when sunlight exceeds 12hrs a day (march-september). I don't have a lot of time to manage it to be honest and that's why I thought the traditional fertilizing would become too much of a hassle (plus the manure odour is not-accepted in the immediate vicinity of the house;)

    I thought that lakewater has a lot of organic material in it (at least this lake), and should thus provide a fairly good and already fertilized water source. EC and pH should also be in the 1.8-2.2 (EC) and 6.0 (pH) region. Plus it would be enviromentally friendly to use it eutrophication-wise.

    I'm no agrologist, but I thought that the most straightforward way to get it rolling to begin with would be to use soil-grown plants and make a little irrigation system that you could turn on and off at your heart's content. Problem is I can't find anything on the internet in which people would have considered lakewater as a ready source of both water+nutrients. Any thoughts?
  5. Feb 21, 2016 #4


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    Staff: Mentor

    I doubt lake water is rich enough in nutrients. Whenever it is, lakes bloom with algae as crazy (till the algae die and the lake stinks as hell).
  6. Feb 21, 2016 #5
    Send a sample to a certified lab.

    Plants need trace amounts of minerals. Is the soil you are using really barren?

    You fertilize with nitrogen, potassium and phosphate. If you don't want to fertilize it, once or twice a year should be enough, you can hire someone.

    This post is really strange. You want to grow some vegetables in a greenhouse. Market worth is probably 100-200 dollars. But you want to spend 10k to check now much nickel, manganese and molybdenum is in the water? And you call it an investment?

    If you are just growing vegetables, you would only take action when there's signs your plants are unhealthy.
  7. Feb 22, 2016 #6
    Well, I believe the price is not everything, and while 10k is obviously pushing it, 1k sure isn't over a few years time. I live in the upper latitudes. There's only a few months of summer season that's noticeable in the grocery store, otherwise the greenery you buy fresh can cost (tomatoes, cucumber, zucchini, apples, pears, etc) up to 15-20$ a kilogram easily, even more. Plus they're usually shipped from a thousand to a few thousand kilometers distance, which I think is a bit crazy in many ways. If I could provide the heating required essentially from otherwise wasted heat, and the power consumption for the extra lighting required would be in the few hundred dollars range / year, I would be matching the cost of the local grocery store pretty much. Pound per pound price probably wouldn't be a lot different from the present, but at least it would be more fresh, and it would be nice to have a little garden all year round.

    Certified lab costs could be getting kind of heavy and impractical if you have to do a before-and-after check a few times a year? Obviously purchasing a certified lab and learning how to use it would be impractical too...

    I thought that if there was an easy way to readings out of everything one should need for growing, then it would be relatively easy to get a storage tank that'll last a good while, fill it up, check it out for all the essentials and add as required, use it and do it all over again, and evade the diagnostics of malnourishment altogether? (no increase from the present required in that section:wink:)

    Edit: Soil could be very barren, since I thought I could have a little hydroponical section!
    Last edited: Feb 22, 2016
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