Soil: Weeding

Good soil is the basis of life as we depend upon it.  Rich, loamy soil with a neutral pH is what every gardener dreams of.  The smell of fresh soil is called geosmin, which is a scent released by happy soil.  Good soil makes for healthy plants, which in turn grow healthy fruits and vegetables.

Soil is different than dirt.  Dirt is what happens on a roadway after a lot of traffic passes over it and the oxygen is compressed out of it.  Dirt is what is left when erosion is allowed to carry off topsoil.  Dirt is what remains after unsustainable farming practices where chemical fertilizers are dumped onto plants year after year until nothing will grow anymore.  Dirt is what most people have when they move into a new house, because to make the property level all the topsoil has been scraped off and buried.  Dirt is nearly dead.  But dirt is an ingredient in soil, and luckily Mother Nature is always trying to repair the soil.  What we call weeds grow in dirt because these are plants on a mission to bring dirt back to life.

Plants have different jobs in nature.  Some have deep tap roots to mine minerals from deep down, bring them up to their leaves which die and transfer the minerals to the surface.  Some are groundcovers.  Some attract insects.  Some fix nitrogen in the soil.  Some provide a shady canopy.  Most provide mulch in the form of fallen leaves, twigs, flowers and fruit.  Some provide habitat for animals, whose droppings fertilize the ground.  Plants help each other in a symbiotic relationship, and permaculturalists call a set of these plants guilds.

Now look at weeds in a vacant lot and try to identify them.  Wild radish?  It has an enormous taproot that breaks apart hard soil, then mines deep minerals and delivers them to the topsoil in the form of leaves.  It also attracts bees and other pollinating insects.  As does mustard, which has a very tough root system that also breaks up hard soil and creates tunnels for worms and other soil creatures to move through.  As the plants die off, so do the roots, which decay and feed the microbes and worms, whose castings turn dirt into perfect soil.  Grasses hold onto the soil keeping it from eroding away, shades the soil from harsh sunshine, retains water  and provides good habitat for worms as well as food for birds, depending upon what type of grass is growing. All plants have a purpose, even if they aren’t in their native environment.

However we don’t want our gardens to be like vacant lots.  Usually, quite the opposite.  Many people will look at their backyard full of weeds and poor soil and decide just to dump white sparkly rock all over it and stick in some unhappy cactus.  These people are actually much kinder to the soil than those who start the relentless, expensive, laborious and deadly cycle of spraying chemical weed killer, dumping on chemical fertilizer, forcing plants to grow in areas not suited to them and yet never creating soil.

When you use permaculture practices in your garden, the most work is done in the first year.  You plan your garden for functionality, plan plant guilds, plot out your own usages and desires, and then plant accordingly.  You may plant close together, but keep in mind the needs of the adult tree.  Don’t plant invasive plants unless they are properly contained.  Don’t plant vines without installing support systems such as trellises first.  Lay the groundwork for your garden.  Don’t spray.  Don’t pour lots of money into chemicals.  Don’t even till unless your soil is horrible and you can’t wait to plant (and then, only till once and then never ever again!).  There is a lot less physical labor to do in a first year permaculture garden than one with chemicals, and none of it involves poison!

Permaculture makes you look at everything in different ways, even things that conventionally seem bad.  Instead of looking at your weeds as devil spawn, look at them with a view to what their purpose is in the garden.  What are they telling you about the soil?  I’ve talked about this in earlier posts, about what type of soil supports different types of weeds.  For instance, nettle grows in high nitrogen areas.  Now think of the weeds as a potential crop.  Lambs quarters, purslane, even stinging nettle are all edible (boil the nettle briefly to dissolve the acid) and very healty for you.  Dandelion wine!  Or think of the medicinal values.  Watch your weeds for awhile. Do birds eat the seeds?  Are they covered in ladybugs?  So now that you know your weeds a little better, you may think more fondly of them and perhaps allow some of them to live.  Or even reserve a corner of the property for weeds to grow just for those birds, insects and your own harvesting.  I’ve allowed purslane and scarlet pimpernel to grow over newly planted areas because they helped hold the soil, preserve moisture and helped prevent more nasty weeds from growing.  Now you’re thinking: but what if they reseed?  Well, of course they’re going to reseed unless you don’t let them live that long.  Seeds are coming onto your property via air, animals and your own shoes every day.  There is a horror about reseeding weeds that is all blown out of proportion.  Have you ever cut all the weeds and had none come up the next year?  Only if you dump Roundup or other chemicals on plants and kill them and everything around them in an annihilation of all that’s good along with all that you don’t want, do you keep anything from growing in that area.  So how do you get rid of weeds?  Okay, hold that thought.

How makes up good soil?  Decomposed organic matter.  It is actually the microbes and worms in the soil that make soil alive and healthy, and they are decomposing all that organic matter.  How do you get good organic matter?  Haul truckloads of horse manure from a farm?  Save kitchen waste?  Have a worm bin and harvet the castings every six months?  Wait until trees are mature and harvest the leaves?  Well, yes to all of these, but in the meanwhile, as it often is in nature, the answer is right in front of you: the weeds!

That’s right!  Weeds are just compost that hasn’t happened yet.  The fastest way to develop good soil when you have no other resources (or not enough resources) is to help nature along.  Define your walkways (where foot traffic will compress the soil and where you don’t want anything to grow), and then when you pull weeds, toss them in your garden beds.  If you weedwhip or mow, rake the cuttings into the beds.  If you do this prior to the weeds setting seed, fine, but don’t lose sleep if you haven’t.  You’ll grow some more weeds… great!  More compost!  I hand pull most of my weeds and then throw them in the guilds under the plants, root ball up.  Within a few weeks they have decomposed, and all those nutrients they were holding in their leaves and roots have been delivered to the soil in the same areas. (If you have different types of soil on your property, keep the weeds near where they grew because they were busy amending that particular soil).  The layer of weeds will also suppress other weeds from coming up, and will hold in moisture.  Sure beats hauling weeds to a compost heap, and certainly beats having the trashman haul off plants that are holding nutrients from your garden soil!

There are exceptions to this practice.  Invasive weeds such as Bermuda grass, Johnson grass, and anything that spreads via underground runners (rhyzomes) should not be handled this way.  These useful plants for a vacant lot are terrors of your garden.  However they can become useful.  If you have a compost heap that really heats up, you can cook the weeds in it.  What I do is put the weeds in an old trashcan, put the lid on it and let it sit in the heat for weeks until the weeds are cooked and completely dead.  If it is Bermuda grass or Johnson grass, I also pound a stake through its heart.  Then I compost it.  Putting it in a trashbag works, too, but then you’d be contributing to the plastic industry in one more way and also to the landfill.  I have set out trashcans with Johnson grass in it to go to the dump when I had so much that I had no place to cook it, and figured that sending organic weed material to the dump really can’t hurt.

How does one get rid of invasive weeds without spraying?  Relentless hand-pulling in combination with occlusion, which is covering it with plywood, thick layers of cardboard, black plastic or whatever you have that will deprive it of what it needs to live.

This has been a long, lecturing post, and I apologize (if anyone actually has read to this point!) .  I want you to look at the varied functionality of everything in the garden.  If you have a problem, can you turn it into a benefit?  For instance, if you have a wet clay area, why not harvest the clay from it to build a cob oven or garden feature, and let the depression become a natural pond?  Or sheet mulch that area (what some people call lasagne mulching), which I won’t go into here but simply search the Internet for it and you’ll find hundreds of examples.  Or plant peppermint or spearmint, or some other wetland-loving plant such as watercress… all of which are edible.

In subsequent posts I’ll talk more about different types of weeding and soil building.  For now, go