Permaculturists everywhere are crazy about patterns. We are taught to “zen-out” so we can observe patterns in nature and society. But if patterns are the glue in permaculture, how do we begin to pick apart the patterns that we can’t even see with the naked eye?
Enter world renowned soil biologist Dr. Elaine Ingham and her rowdy band of critters known as the soil food web. Dr. Ingham has spent decades observing and unlocking the secret patterns of the soil food web. Through her work, we have a better understanding of the incredible diversity of organisms that make up this mysterious world. They range in size from the tiniest one-celled bacteria, algae, fungi and protozoa, to the more complex nematodes and micro-arthropods, and on to the visible earthworms, insects, small vertebrates and plants.
We are now able to discern that every field, forest, or pasture in the world has a unique soil food web pattern with a particular balance of bacteria and fungi and various levels of complexity within each group of organisms. These differences are not only the result of soil, vegetation, and climatic factors but are dramatically affected by land management practices as well. Only by understanding these new patterns can we make better land management decisions that are optimized for the differences in croplands, rangelands, forest lands, or gardens.
This research provides us with an incredibly advanced starting point, but there is so much more to learn and put into practice when it comes to soil science in relation to permaculture. If we saturate ourselves with Dr. Ingham’s work we can take it further, pioneering new methodologies in permaculture, thereby unlocking more secrets from these ancient patterns. We can learn to integrate soil food web enhancing strategies in all activities of farms, ranches, forests and backyard gardens. Only we can do this work, and now is the time!
Dr. Ingham’s famous Soil Food Web Course is finally being taught online and is accessible to anyone, anywhere in the world. There are so few soil experts out there, so this should come as welcome news for us all. It’s time to inoculate the planet with this important work. Let’s do this!
The course starts June 2nd, 2014. Sign up here!
Would love to know how to grow veges in poor sandy soil that requires tons of humus and manures to keep it active. Six feet down there is a clay base with plenty of sandstone rocks scattered throughout.
What can you clever ones suggest?
Mix clay with the sand for quick results or layer it on top cover with compost and mulch and let the worms do the mixing for you. Personally I’d take the slower path and have the time to observe and adjust.
Agreed Anthony. I remember Geoff Lawton saying he was dealing with a site with a particularly sandy soil a long time ago, and tried digging clay into it for a while, but gave up, as it was too time-consuming and difficult to get the two soil types to ‘blend’. Then later he found the soil life did a perfectly fine job of ‘mixing’ the layers all by themselves. As you say, throw in some compost and mulch – something to encourage worm and microbial activity – and they’ll get the job done. If it’s really, really sandy, then don’t skimp on the clay.
May be the article sandbar cropping in Bangladesh will throw some light. On the banks of rivers in Bangladesh people grow pumpkin, water melon, lettuces, squash on sandbars by using pit cultivation technique adapted to the local conditions.
I would suggest the tried and true method of “No Dig Gardening”. This way you can grow whilst building your soil up.
I have to work with sand (not sandy soil: white sand from a glacial terminal moraine) covered by maybe 2-4 inch of somewhat acidic topsoil formed over the course of decades by a rarely mowed ‘lawn’ and steadily needle-shedding conifers. My climate is cool-ish continental and rather dry in the summer months (northeastern Germany – look up the climate data / hardiness zones for Berlin if you want comparison).
I’ve tried hugelkultur beds or table-high raised beds filled with lots of composting materials. These get far too dry even if the sides are covered with a water-proof material (the sand beneath just drains too well), and they also tend to freeze solid in cold winters (below -15°C) because they have so much surface area. For example a few years ago, the strawberries on the raised bed all died, while a few volunteers in the sand right beside it survived without any attention.
I have since started to do the same basic construction of layers of compost-sand mix (about 60% compost to 40% sand), compostable materials (leaves, grass, weeds), and half-rotted old firewood, but I now bury the whole construction so that the bed surface is level with the surrounding ground in the end. Yes, that means a lot more work to dig some 2 feet deep, but it seems to help with the temperature aspect, and the bed gets much more earth worms on account of being easily accessible. Some generous additions of woodash (using dead branches and pinecones from the conifers, because they don’t compost well and also make the compost acidic) help raise the pH to a neutral level and add some potassium and phosphorous since I don’t have access to clay soil for the minerals. You have to add new woodash every year (about a handfull per square meter), though, because in sand soil, everything soluble will wash into the lower regions and become inaccessible to shallow-rooting plants. The bits of charcoal will add up over the years to help water retention.
However, any very water-thirsty annual plant (like tomatoes) goes into large pots. Trying to get those to survive in the sand is just a waste of water and compost. Those big, black troughs you can buy for mixing cements are just the right size and much cheaper than actual planting pots – just don’t forget to put some holes in the bottom. I’ve also made some fairly sucessful large planting ‘pots’ from old 3-sided furniture (like wardrobes or kitchen cabinets), but those will only last 5 years or so if you plant anything in it that will need frequent watering, as the wood-pulp material of cheap furniture will soak the water up, even if it’s covered in plastic sheeting. Works very well for flowering shrubs with shallow roots, though.
As for perennials… Well, you’ve got to choose variants that will tolerate occasional drought and “light soils”. For apples, that’s not many variants, sadly. Plums are generally easier. Nectarine and peach do surprisingly well, in a wind-protected, sunny spot. Walnuts seem to do well (we’ve got a huge old tree, and the nuts grow easily if we don’t stop them), but you’ve got to choose a variant that will wait with the flowering after you can be sure the frost is over (also, it takes 10-20 years for the first harvest, so that’s more an investment for the next generation). Hazel… well, it grows, but I haven’t seen it carry much nuts yet – though that may be a pollination problem. However, currants and gooseberries do quite well in my area, and blueberries grow naturally in the pine woods around here (they like the acidic topsoil). For bushes and young trees, I dig a generously sized hole, 1 or 2 feet deep, and fill it with compost, some small sticks and other rough stuff that doesn’t compost quickly, and a few handfulls of shredded cow horns/hoofs. The latter are a commercial nitrogen fertiliser that goes into solution only very slowly (over a couple of years), so it doesn’t wash out as quickly as blood meal or guano. I’ve been using human hair and fingernails, too, but they’ve got to be untreated and you’re going to collect for a long time to get enough. Once that initial storage of fertiliser is used up, your tree hopefully will have a big enough root system to maintain itself. My currant bushes get mulched with extra compost and a little bit of potassium-fertiliser each year, though. I suppose in your case, compost with some clay would be enough. Maybe sow some clover or other nitrogen-aggregator green mulch below. I’ve read that comfrey will pull minerals from the deep soil with its long root and make them available to other plants (also, the leaves dissolve very quickly, making fertiliser sludge). I haven’t tried that yet, but when I was I kid, we had a big rhubarb plant which has a similar growth pattern, so it stands to reason that comfrey should survive as well.
Besides the comfrey, if you don’t want to use commercial fertiliser, maybe looking into herbal liquid fertiliser is worth the effort. Stinging nettle will grow on sandy soil and contains quite a lot of nitrogen. If you’re growing tomatoes, the leaves make good liquid fertiliser, too. I use the lower leaves I have take off in the beginning to fertilise the growing plants through the summer. Just collect a bucket full, fill it with water, and let it sit for a couple of weeks until the leaves dissolve. Smells awful, but so does manure – precisely because of the nitrogen content.
I’ve also tried experimenting with the technique of putting “ramial chipped wood” in very low raised beds (for the strawberries) and around fruit trees. The idea is that compost is fairly water-soluble and washes out, and also gets metabolised by bacteria quite quickly. Whereas a layer of RCW is supposed to build up a fungus network which eventually transforms the wood into long-chained, carbon-rich humic acids (humus), which stay more permanently in the soil and help water retention. Supposedly, this builds up soil carbon considerably faster than just adding compost. I’ve just started this year, though. Google the term for details, but basically, you just add a few inches of thin branches of deciduous trees and bushes, cut to the size of a finger max, work it in a little into the topsoil, and then wait. Ideally, it’s done in the cool/rainy season, and you’re not supposed to let the wood pieces compost first (you don’t want too many soil bacteria). Mixing in a bucket or two of topsoil from a deciduous forest helps innoculating your soil with the right fungi – the idea is to replicate the soil biology of a forest, not that of a field, because our fruit trees originally were forest adapted and need those fungi to help them access nutrients.
I saw Dr. Ingham at the Permaculture Voices conference in California last March. She is a great speaker, incredibly knowledgeable and more importantly – quite engaging. Sometimes all of that sciency stuff can put you to sleep but she kept a packed room of people on the edge of their seats for two and a half hours. Everyone left ready to buy their own microscope and get to work studying their soil!
If you are out in San Diego this early November, Dr. Elaine Ingham is teaching a 5-day intensive. https://sdsustainable.org/event/soil-foodweb-with-dr-elaine-ingham/
What a beautifully written article, Chi – thank you! I would love to take this course.
Building some wicking beds would be a good addition to growing food on sandy soil and would be more quickly productive while you wait for the garden soil to get to where you want it.