By Julia Frisbie
Posted April 30, 2021
Weeds are inevitable. When you notice them, you can choose to get grouchy or get curious. I do some of each. When I pay attention to my weeds, I learn a lot about my soil. What follows is a “who’s who” of common weeds in my garden, categorized by what I think they’re trying to tell me.
I’m sure there are other weeds in your garden (and in mine) who didn’t make the list. Grab a field guide and try to identify them and learn about their preferred habitats. Sometimes if you have a great diversity of weeds in a single area, they may send you mixed messages, so you’ve got to interpret them loosely. There’s not a perfect 1:1 ratio between weeds and the clues they give us about soil health. Plant communities are incredibly complex. But I hope that the things I’m learning from my weeds will spark your own curiosity about the weeds you live with!
Weeds that say, “PLEASE MOVE THE CHICKENS AWAY”
Dock (genus Rumex) thrives with low calcium and extremely high magnesium, phosphorus and potassium. A big patch of dock tells me that the area is over-fertilized and I need to give it a rest from chickens. Dock loves heavy soils, and tries to be a good neighbor by breaking up compacted soil via a long taproot. If you want to address compaction, tillage is only a temporary fix– and in the long run, it compacts the subsoil even worse. A gentle broad-forking or a rotation of long-rooted daikons left to decompose in place is a better solution. Or, if you’re a laissez-faire gardener like me, just keep cutting down the dock greens and leave the roots in place. I’ve read that dock is edible and medicinal, but it’s high in oxalic acid and quite bitter, so I tend to chop-and-drop it (like many permaculturists do with comfrey) instead of eating it. The leaves and stems make great mulch.
Cleavers (Galium aparine) give me a rash, so I’m pretty vigilant about pulling them out. They flourish in high-nitrogen soils, so they tell me to give that spot a rest from the chickens. This herb has a long history of use in folk medicine, but I have not experimented with it. Too itchy. I have no pictures to share, because it’s out of season right now.
Weeds that say, “PLEASE BRING THE CHICKENS OVER”
Vetch (genus Vicia) tells me that the soil has low fertility, and vetch is here to help. It’s a legume, a relative of beans and peas, and a symbiotic relationship with bacteria on its roots allows it to fix nitrogen from the air pockets of the soil. If I see vetch, I add chickens. I think it’s pretty, and don’t usually bother to pull it out. Again, no pictures because it’s out of season, but I look forward to its return in June.
Weeds that say, “PLEASE IMPROVE DRAINAGE”
Buttercups (genus Ranunculus) love wet feet, and show me exactly where my drainage issues are. Thanks to the relentless feedback of buttercups, I’m slowly terracing a soggy slope. Buttercups also prefer acidic soil, so I like to see them at the feet of my blueberries and azaleas, but if I want to grow annual veggies in their spot I may need to add lime. Buttercups tend to form a solid mat of greenery that can choke out other plants, so I try to remove them. On the plus side, their flowers are beautiful, and they always make me sing “Build me Up Buttercup.”
Weeds that say, “PLEASE ADD MORE MULCH”
Quackgrass (Elytrigia repens) thrives in heavy clay soil, and tells me that I need to add more layers of organic material. The more organic material I add, the easier it gets to remove its spaghetti-like rhizomes.
Hairy Bittercress (Cardamine hirsuta) specializes in disturbed soil. It’s a relative of radishes, broccoli, and kale, but unlike its domestic kin, it has an incredibly fast seed-to-seed cycle. By the time other annuals are getting started in the spring, it’s already fully grown and flinging its progeny into the world (which explains the common name “shotweed”). For this reason, it’s one of my son’s favorite early greens to forage. It tastes better than the name suggests! A plant growing here and there is normal, but when I see a big patch of hairy bittercress, it tells me that the soil has been disturbed too often. (Disturbance in my yard is usually caused by chickens or toy tractors, but in other places it can be caused by tillage or by repeated herbicide application.) This place needs a deep blanket of mulch and a long rest.
Weeds that say, “PLEASE KEEP DOING WHAT YOU’RE DOING”
Purple deadnettle (Lamium purpureum) tells me that I have a neutral pH and relatively fertile soil. Hooray! They’re another favorite for spring foraging, for us and for the bees, with their fuzzy, mild-flavored leaves and their tubular purple flowers. They’re actually more closely related to mint than nettle (the square stems are a dead giveaway), and I control them similarly to mint, by simply pulling or cutting them wherever they look like they’re about to swallow up their neighbors.
Dandelion (genus Taraxacum): Dandelions aren’t picky; they’ll live just about anywhere. They’re edible and medicinal, and important for the bees. I tend to let them be. I think their flowers are beautiful, ESPECIALLY UNDER A MICROSCOPE!
Look at all those pollen grains, sparkling like geometric love notes to an unknowable future.