I told you it was coming, didn’t I?
Well, here it is. I’ve been getting serious about my (extremely) small-scale agriculture on my small plot of land (it’s a pretty standard quarter-acre lot), and I’ve got some interesting things to write about.
As I mentioned in one of the prior parts, organic agriculture is all about feeding the soil, not about feeding plants. If you have healthy soil, you’ll have healthy plants and good crops; if you don’t have healthy soil, either your plants won’t grow, or you’ll be forced to load your soil with chemicals, which will only kill it further. So I’m concentrating on feeding my soil, making it healthy and productive of good plants. To do that, though, I need to learn what its present condition is. And to do that, I needed some handy-dandy soil health calculation detector thing. So I broke out my chemistry set (by which I mean I bought a soil-testing kit at a gardening store) and started to work.
To the right, you’ll see one result of said handy-dandy soil health test kit. (The tubes are reusable; the packet came with supplies for ten tests.) Essentially, you get a little bit of soil, mix it in with water and some nifty chemicals, conveniently packaged as small solid tabs, and judge the chemical contents of your soil by the color of the resulting fluid. In this example (which applies to my apple plot), we’ll start from right to left. The blue tube contains the test for phosphorus; phosphorus is vital for healthy root growth. This shade of blue indicates that I have a healthy amount of phosphorus in this particular patch. If I didn’t, bone meal would be the best organic fertilizer to mix into the soil to improve its phosphorus content. The next tube is green; that’s the test for the pH of the soil (that is, whether it’s acidic, basic (alkalinic), or neither). This shade of green indicates that my soil is almost exactly 7, the pH of water, neither acidic nor basic. That’s not really good; most plants want soil that’s a little acidic. Apples, for example, like a pH around 6 or 6.5. However, it’ll do for now. To make soil more acidic, raise the bed and improve drainage; to make it less, apply lime.
The third tube is yellow-capped, containing a gray liquid. This contains the test for potassium, which helps produce fuller blossoms and, of course, fruits. This shade of gray indicates that I’m a bit low on potassium. Rock potash or hardwood ashes are the answer for that. Finally, the red-capped tube contains the test for nitrogen, the all-important element which encourages healthy growth, particularly of leaves and stems. You can barely tell that the liquid is pink, and it’s supposed to be fully red, so I’m quite low on nitrogen in this patch. The solution is to apply a good dressing of dried blood (often sold as “blood meal”), which is very fast-acting, so don’t apply it too long before planting.
What’s all this chemistry stuff, anyway? Well, the good gardener is, to a limited degree, a good chemist. An off-the-cuff, inexact, eyeballing type of chemist, but a chemist nevertheless. A healthy soil is all about a healthy chemistry, and it’s important to know which plants require which elements more, and how to tell (based on the plants) when the soil has a shortage or a surplus of certain elements. Let’s begin, shall we?
Plants depend most significant on the Big Three, the three major elements. These are carbon (C), hydrogen (H), and oxygen (O). Hydrogen and oxygen generally come in their mixed-together form (we often call this “water”, H2O), and carbon is so omnipresent that a shortage is pretty well unheard of. But without these three elements, a plant just isn’t a plant. Literally; it can’t exist. These elements are so vital that Hamilton simply presumes them, and doesn’t give them a name, calling what I call the minor elements “major” in consequence; however, I compulsively categorize, and so major elements is what I’ll call them. Make sure your plants get their water!
Next come the six minor elements, which are vital and generally cause the problems that you’re going to have with keeping a healthy soil. The first is nitrogen (N), responsible for good green growth. Dried blood is the best source of this if you get a shortage. Decomposition (rotting) of organic matter requires lots of it; fortunately, our atmosphere is 70%+ nitrogen, so there’s plenty to go around. However, not all of it’s incorporated in the soil, and that’s where most plants need to get it. (Not all plants, though; we’ll get to that in a minute.) That’s why it’s important that, when you work organic matter (compost and manure) into your soil, you make sure that it’s well-rotted first; otherwise, the bacteria which rot it will take the nitrogen they need out of the soil and use it themselves, depriving your plants of it. This is counterproductive, to say that least. If your compost isn’t quite rotten yet, make sure you compensate for that with extra nitrogen, probably from dried blood.
Now, there are some plants that don’t get their nitrogen from the ground; they get it from the air instead. The most useful of these are beans; I say they’re the most useful because they’re a very healthy, protein-rich foodstuff as well as being very good for the soil. They’re good for the soil because they not only don’t take nitrogen out of the soil, they put it into the soil. That is, they take their nitrogen from the air and work it into their own selves, including their roots. Some of this gets into the soil from there. When this happens, we say that the plant is fixing nitrogen, or is a nitrogen-fixer. Other edible examples are mints and clover; an inedible (in fact, poisonous) example is vetch. This makes such crops ideal for nitrogen-poor soil. (I’m growing lots of beans in my own nitrogen-poor plots.) Mints and clover are edible, but are also useful as green manure; you grow them for the purpose of plowing them back into the soil. This is good with them even when unrotted, because they take nitrogen from the air and add it to the soil. When you harvest your beans, cut them off at ground level and toss the above-ground bits into your compose bin; leave the roots in the ground, where they will enrich the soil with nitrogen.
Of course, you don’t want too much nitrogen, or your plants will grow too fast. This results in weak, soft growth, vulnerable to pests and disease. A deficiency of nitrogen will result in stunted plants, and leaves, particularly older ones, will yellow all through. Dried blood is the cure-all; it’s like a quick shot of nitrogen for the soil.
The second minor element is phosphorus (P), which is vital for good root growth. The better the roots, the stronger the plant. Plants grown in phosphorus-deficient soil will be slightly stunted, but also weak because they have weak roots. The leaves will also start to take on a bluish tone, particularly the older ones. The best source of phosphorus is bone meal (just what it sounds like: ground-up bones).
The third minor element is potassium (K), also called potash. An excellent source of potash is, obviously, rock potash; it’s also contained in hardwood ashes. Potassium helps produce larger and well-formed blossoms and fruits. If you don’t have enough, you’ll know, because your blossoms and fruits will be small. Too much potassium, though, and your plants will have trouble taking up magnesium, which causes its own problems.
The fourth minor element is magnesium (Mg). Magnesium is an element of chlorophyll, which is what helps plants survive with nothing but water, soil, and sun; a deficiency will result in yellowing in the leaves, starting between the veins. The best way to add this to the soil is to not let it get short in the first place; always provide your soil with lots of organic matter (compost or manure). If you’ve already planted, try seaweed if you’ve got any; seaweed meal or liquid seaweed (the liquid that results from soaking seaweed in water for an extended period), or liquid manure (made the same way, but with manure).
The fifth minor element is calcium (Ca), which does all sorts of chemical things in plants that are too complex for me to really grok at this time. Bottom line, you need it. Hamilton assures me that a deficiency in an organic garden is quite rare; this is because organic gardeners provide lots of organic matter to the soil. However, if you do have one, mix into the soil things like eggshells, oyster shells, and hardwood ashes. Ground limestone, or lime itself, would also be good, though don’t let it burn the plants.
The last minor element is sulfur (S). Sulfer is a vital ingredient in proteins and helps produce chlorophyll. The answer: you guessed it! Apply lots of organic matter to the soil. That’s really the bedrock of all organic agriculture: provide as much organic matter to the soil as you can. What you take out in the form of fruits and vegetables, you must return in the form of compost or manure. You can’t get something for nothing, pay off debt with debt. It’s that simple.
Finally, after the minor elements come the trace elements. These are necessary elements, but only in very small quantities. Iron (Fe) is needed for the formation of chlorophyll. Zinc (Zn) and copper (Cu) are required to activate certain necessary plant enzymes. (No, don’t ask me what an enzyme is; something biological chemical of some sort. Check Wikipedia.) Manganese (Mn) helps form proteins and chlorophyll. Boron (B) is necessary for growth. And finally, molybdenum (Mo) is needed to produce certain proteins. I’m not going to explain them all; this post is already ridiculously long as far as blog posts should go. All I can say is, go buy Hamilton! Seriously! It’s worth every cent!
So, I’ve produced my apple patch. You can see it there on the right, in all its still-lots-of-dirt-on-the-grass-part glory. (Yes, I clean it up afterward.) I gave it a little bit of bone meal to provide phosphorus for healthy root growth and plenty of dried blood to improve the soil’s nitrogen content. That should also acidify the soil a little bit, which the apples will like. The apples arrived today; they are three-foot barerooted trees, one Granny Smith and one Braeburn (two varieties that blossom at about the same time and will happily pollinate each other). I’m going to a professional conference tomorrow, but in the morning, before I leave, I shall plant those trees. I’m very excited about it. I intend to keep them manageable in size by judicious pruning, training them as festoons; this is a slightly complicated process that I’ll explain at the end of the summer, when I start it. I’ll take a few pictures at each step along the way, as always, and let you all know how it goes.
Praise be to Christ the King!