Most gardeners are doing it wrong. Yes. I said it. They're doing more work than they need to and spending money to correct the mistake they're making without even knowing they're making it.
When I was a kid helping mom in her gardens, I learned to pull anything that I (or she) didn't plant there specifically. Anything. A perfect garden bed was an organized grid of clean rows with bare soil between them. That meant hand pulling, hoeing, tilling, whatever is necessary to prevent weed growth. This makes perfect sense when we consider that most gardening practices of 20-30 years ago in the midwest USA were simply scaled down row crop farming practices. In the 1980s, a farmer with a field of corn and nothing else had something to be proud of. Many (probably most) gardeners still use these practices. Oh sure they've added a few other tricks, but I'm betting that for most gardeners, the sight of a dandelion between their tomatoes triggers a compulsion to pull it.
I understand, the same thing happens to me. But is that really the best response?
What is a weed?
I think, before we can go too far into this, we need to define what a weed is. Traditionally, anything that wasn't intentionally planted was a weed. This could even mean volunteer tomatoes or squash. I can't tell you how many volunteer tomato plants I pulled over the first 10 years of gardening. I almost feel guilty about it now. But is that a fair definition of a weed?
How about we change that a little? Let's say that a weed is anything that doesn't contribute to the garden or benefit us in a way. Does that change what we pull and what we don't? Doesn't it make sense to let a beneficial situation persist? If that dandelion growing between the tomatoes is actually helping us somehow, should we still pull it? Some will say that dandelion isn't helping, it's robbing nutrients and water from the tomatoes. That may be so in some cases, but it's also doing something that tomatoes don't do very well.
Dynamic Accumulators
Many of the plants we consider weeds are called Dynamic Accumulators. This means that they gather nutrients of some sort in their tissues, locking it up for later use. For you, a dynamic accumulator is a reservoir of nutrients. A plant that has locked up a quantity of something you want to store for later.
Many of these dynamic accumulators also send deep roots. Deeper than most things we plant in the garden. That's why they're so hard to get rid of. They're weeds, right? They survive when nothing else does. Have you ever dug up a dandelion? A dandelion tap root can go 18 inches or more into the soil. Most of our garden veggies don't reach deeper than 6-10 inches. What that means for you is that the dandelion is pulling moisture and nutrients from a depth of soil where nothing in your garden can use it. Woah.
No Man's Land (Or No Plant's Land)
Most typical garden plants don't push roots deeper than 8, sometimes 10 inches. This means that any nutrients that have leeched deeper than that are usually lost. They're just gone. Untouchable. Unless you have a few dynamic accumulators in your garden salvaging them. The sweetheart of dynamic accumulators, Comfrey, can grow roots up to 10 feet deep. This guy is the deep sea salvage diver of the plant world, going deep and bringing back valuable nutrients to be stored in leafy growth at the top of the plant. Clovers of all types are nitrogen fixers - they absorb nitrogen from the air and lock it in their tissues. This is free fertilizer, and most people pull it and throw it away.
Not all weeds are beneficial
Certainly, not everything that finds a home in your garden is going to benefit you or your garden in some way. In general, plants that grow a deep root system and do not become invasive are going to help you, and plants that spread rapidly, choking out other growth with spreading shallow root systems are not going to be beneficial. This means that while a dandelion or three is a good thing, grasses of nearly all types are still undesirable even under our more lenient view of what a weed is. To help clarify this a little more, I'll attach some lists of dynamic accumulators at the bottom of this post.
Putting the pieces together
So just HOW do we take advantage of dynamic accumulators in our gardens? By composting. Whether you grow plants specifically for composting as many people in the permaculture world do, or you're more like me and you go pull all those dandelions in the fall and throw them in the compost pile, you're turning something that is traditionally viewed as a scourge into something beneficial.
Let's take a walk through my garden, and I'll tell you what I'm doing now, and how I think all this applies to me and also to you.
The first thing you notice when you enter my garden is that there isn't much bare dirt. There are some areas where crops have been finished and are sitting with a layer of finished compost on top, waiting for fall plantings of garlic, but for the most part, everything is green. The first raised bed we come to has different varieties of tomato plants in cages, some laying on the ground. The area right around the plants is mulched with grass clippings, but the spaces between the plants are filled with different varieties of clover, dandelion, curly dock, wild lettuce, and probably some elm tree seedlings. I leave these plants go until they get so large that they crowd or shade the tomatoes. At that point I grab on and pull. The whole plant goes into the compost bin. Otherwise, I leave them to grow. This doesn't hurt yields one bit. My Amish Paste plants are still approaching 5 feet tall in mid August, even though they were direct seeded (I don't use many transplants, but that's a different story). That carpet of green in between them is helping to preserve moisture and collect nutrients from deep in the soil. The only real management I do, other than removing plants that have started to crowd or shade, is to deadhead anything growing a seed pod. For dandelions this means pulling all the flowers off. On wild lettuce I remove any flowers before they form seeds. I like to leave the flowers as long as possible for the pollinators. Deadheading is easier than weeding, takes less time, leaves a beneficial plant to do its job, and keeps it from overtaking your garden, all at once. Plus, deadheading wild lettuce with a machete can actually be kind of fun. :)
You'll notice that there is no grass. I hate grass. I've let my lawn go mostly wild, it's up to about 30% clover, which is where the chicken tractor sits most of the summer. But the lawn around the garden is still grassy, meaning grass finds its way into the garden. I pull all the grass I can find inside the beds. Grasses in general, though they have their place in nature, have no place in a vegetable garden.
So let's review:
1. Let beneficial plants grow as long as they don't crowd crops.
2. Deadhead them so they don't produce seeds.
3. Pull them all in the fall and put them in the compost bin - or let them die on their own and work them into the soil in the spring.
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| And you thought these were just weeds. |
Can we take this further?
Certainly! Imagine for a moment, a garden where most of the nutrients that leech too deep to be used by vegetable plants are captured by dynamic accumulators. They're brought back to the top, captured in foliage for you to compost or work back into the soil, releasing those nutrients to be used again. Such dynamic accumulator plants are intentionally placed around and in the garden space just for this purpose. To the passerby they look like weeds, but you know they're doing a job that you can't do any other way, rescuing nutrients, preventing soil compaction, and saving you fertilizers.
Chop and Drop
Many gardeners have learned to add perennial dynamic accumulators (such as comfrey) to their garden areas. One possible method to incorporate this into your garden would be to grow an accumulating plant in your garden, and periodically chop it down, leaving the leaves and stalks on the ground. Done early in the year and the comfrey becomes mulch to spread around your tomatoes. Done in the fall, the material will compost over the fall, winter and spring and become nutrients for next year's growth. Comfrey in particular can be chopped several times per year. You can apply this to other plants as well. Large, broad dandelion leaves make great mulch. Pull the leaves off the top of a dandelion, leaving the root in the ground, and throw them down as mulch around the base of a plant. A few dandelions won't make much difference, but if you have a few hundred around the garden like I do, it becomes almost enough to mulch a whole bed of onions.
To Summarize
Take some time to think about whether those plants growing between your cabbage are helping or hurting your efforts. You just might be shooting yourself in the foot by pulling them all.
List of Dynamic Accumulators - Courtesy of the Oregon Biodynamic Group.
