compost in urban veg gardens

Discussion in 'Organic Gardening' started by sluggo, May 13, 2009.

  1. sluggo

    sluggo Active Member

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    Hi,
    Maybe this is a dumb and oversimplified question, but would there typically be any need for further fertilization in small plot veggie gardens other than digging in compost in the spring? This is what I did this spring for a couple of plots.

    On the other hand, I'm also planning some containers which I think may be a bit more complicated for fertilization because of the potting mix used and its compatibility with drainage, water retention and aeration. For this I also wanted to use some easy to obtain organic fertilizers but I've gotten lost in the myriad of somewhat strange ingredients and how they can be combined to produce something close to a 1-1-1 NPK ratio (or even a 2-1-2 or 3-1-3). I have no idea on what my compost NPK ratio is, so I'm a bit reluctant to rely on it in a container.

    thanks
     
  2. greengarden bev

    greengarden bev Active Member

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    Your question leads to the proverbial can of worms (chem vs. organic) which is probably why it hasn't been answered yet.

    There are a couple of approaches you can take for the garden.

    1. Assume that the your "virgin" soil plus the spring-added compost will be enough. This being the first year for your garden, the soil hasn't had a lot of demands made on it and the fertility should be just fine-- unless it is already degraded (construction fill, subsoil/topsoil removed). The need for soil fertility will become more important in subsequent years as you make "withdrawals" with each crop. Consider not only what you add to the soil (compost, organic fertilizers) but also what you do (cultural practices that build soil health: cover crops/green manures; no-till with deep mulch; rotations; interplanting; etc). Monitor the quality and quantity of your produce (and soil) and learn from observation and research what your soil needs.

    2. Get really technical and have a soil test done. Pay close attention to the nitrogen levels. Make a list of all the vegetables you will be growing and look up their nutrient requirements, especially N. Fertilize as necessary. Monitor your produce for quality and quantity, but keep doing regular soil tests to determine the fertilizers needed.

    As you can guess, I'm not a proponent of the second (industrial) method because it tends to treat soil as merely an inert "substrate" onto which the appropriate combination of chemical nutrients is added. I say "tends" because it is possible to take the industrial route using organic fertilizers. This leads to a long and dangerous discussion about the meaning of "organic"...

    Of course you can find your own point on the continuum between these two approaches. This will take time and patience but it'll be part of what makes gardening fascinating, fun and inherently worthwhile-- and one of the ultimate creative activities.

    re: container gardening. Maybe someone can do the research for this. Logically, since container soil is "dead", organic fertilizers ought not work. They need the presence of the microherd to make the nutrients in organic matter and minerals available to plant roots. But I've used fish emulsion and liquid kelp on containers, and they do work. Don't know why. Curious to know.

    re: NPK of compost. If you're buying commercial compost, the NPK should be listed on the bag. If you're using home-made compost, the values will vary according to the feedstock you've used. Plants will generally give you no more than a 1-1-1, probably substantially less. Manures can give you up to 3-1-1, depending on the animal. I'm really generalizing here-- my point is that manure-based compost tends to be more high-test. You could have it tested at a lab if you really want to spend the time and money. Someone somewhere on great big InterWeb has probably already listed the average NPK by feedstock.
     
  3. sluggo

    sluggo Active Member

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    I've read various postings and musings on organic vs. not organic and I believe I have a good feel for the debate. A bit off-topic, but I'm much more interested in sustainability as opposed to organic labeling. In any event, I think one of my garden beds could use some fertilizer. It is producing slower than my other bed, although it probably is not getting as much sun. I'm now thinking that I will use some Grotek Fish Plus (3-1-1) or maybe some alfalfa meal to help kick-start things with a bit of N. I'm not sure where to easily get alfalfa in Vancouver, and driving out to Langley (45km round trip?) to a feed co-op is not an enticing option. The alfalfa would be good soil amendment in the fall and would be good for my compost.

    Perhaps in the fall or next spring I will do a soil test. Thanks for the thoughts and the general NPK for compost.

    cheers
     
  4. 1950Greg

    1950Greg Active Member

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    There could be someone in the Southlands area of Vancouver selling alfalfa pellets.
     
  5. soccerdad

    soccerdad Active Member 10 Years

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    I can't say what is needed in the early years of having a garden, but I think the previous owners of my place composted - they evidently sought to add iron to the soil by tossing bent nails in the garden (for years I picked them out of the soil at planting time; still find a dozen each spring) and although one seldom composts nails, that attitude would presumably be accompanied by composting - and I have never added anything but compost in the 25 years since we moved in. I can't imagine any reason for using artificial stuff.
     
  6. greengarden bev

    greengarden bev Active Member

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    I use alfalfa fines and pellets quite a bit in all my garden beds, especially the new ones. It's an excellent all-round soil amendment-- but it's not particularly high in N. About 2-2-2 if I remember correctly. For the veggies, if you want a good pre-plant for the soil that is fairly high in N, you could try soy meal (about 6%).

    Soccerdad, do you think that the previous owners may have just tossed nails from a renovation project out onto the garden? Maybe they replaced the siding or the roof and just discarded the old nails.

    There are many "compost only" people who have excellent, healthy and productive gardens. But growing veggies year after year makes a lot of demands on the soil and I've always thought that soil needed more than compost which, although indispensable, is not really considered a fertilizer. I haven't done much research on this and I probably should. Where I live we have easy access to "organic" amendments, so I use those in addition to my home-made compost (spent sunflower seeds from an oil press plus kitchen scraps plus horse manure).
     
  7. growest

    growest Active Member 10 Years

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    sluggo--one strategy for containers in this area is using Seasoil, along with perlite to improve the drainage. This material is totally organic plus has a good balance of nutrients at least for a start.

    I do love alfalfa for additional nitrogen, but one of the many organic blends available might be simple and give dependable results. I use mostly fish and kelp liquid fertilizers on veggies after planting but there are many ways to achieve the same goal.

    Like bev says, it's a can of worms talking about generalizations of how to fertilize your veggie garden. Many of us can ramble on for so long with our own experiences, and we all have pretty good results so it's hard to prove the right's and wrong's of our individual systems.
     
  8. soccerdad

    soccerdad Active Member 10 Years

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    Bev, the house has always been stuccoed and the nails were not shingle nails. In fact they tended to be 1.5 to 2 " long, and construction nails are - or used to be, when I worked in construction years ago - longer than that. They were in varying degrees of decomposition. So I am confident that they had been tossed there over a number of years.
     
  9. vitog

    vitog Well-Known Member

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    One organic item that seems to add a lot of fertility to garden soil is kitchen scraps, especially those containing meat and bones. I've been burying every organic scrap item from the kitchen for over 30 years and have found that plants love it. From the way that tomatoes grow when planted above such material, I can tell that it must be rich in nutrients.

    Of course, you have to have a fenced garden to keep dogs out of the garden; and racoons occasionally dig up some items: they particularly like fresh crab remains. However, all it takes is some old chicken wire or something similar laid on top of the buried garbage to keep the racoons from digging it up. After a couple of weeks, they will lose interest. Chicken bones disappear pretty quickly, but thick beef bones will be around for years. I've never found this to be a problem; but if you find big lumps of bone objectionable, you can easily break them into small pieces with a hammer.

    Note that kitchen scraps are not a good item for the compost bin; they attract vermin in such locations. However, rats and mice do not seem to be attracted to buried garbage.
     
  10. sluggo

    sluggo Active Member

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    Thanks everyone. So far my soil + compost is great so no worries there, but point taken on keeping an eye on it as time goes. The bit of info here on compost gives me clues to work from.

    I managed to get some alfalfa meal from Rona, it came in a bucket by Gaia Green. I amended my raised square foot garden (consisting of compost, vermiculite and peat) with it.
     
  11. canadiyank

    canadiyank Active Member

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    I only use compost and then mulch (usually with grass clippings, sometimes cardboard covered with grass clippings). I have clay soil and it works well, I just dig it in each spring. If I have some compost during the growing season I just side-dress the plants with it.
     

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