What Your Weeds Say About Your Soil

So. You decided it was time to start a garden and become the ‘green thumb guru’ you’d always dreamed you could be. Things were progressing smoothly until you began to notice a few nasty weeds making their home among your plants.

Don’t be discouraged!

While weeds may be dubbed ‘undesirables’ in the gardening community, don’t be so quick to pass judgment. So many of the plants that have been labeled as troublesome are actually pretty amazing in their own right; each and every one serves a valuable and unique purpose—medicinal, for example—and some can give you some pretty telling insight about the health of your soil.

Say, you notice your lawn is becoming lush with clover when you’d rather it wouldn’t. Odds are, a low level of nitrogen in the soil is causing it to grow. The remedy? Just apply a high-nitrogen fertilizer on your lawn to reach a balance. Now, this isn’t a perfect science, but these weeds can give you useful hints as to what’s going on below the surface if you take the time to observe.

Here are some of the most common culprits to help you get started learning to “read your weeds”:


Ah, dandelions. Everyone knows them and it seems everyone has them. This plant has a bad reputation, due to its amazing propensity to grow and spread like wildfire. However, it’s actually quite a sweet flower that can be harvested for green salads and soups—evensmoothies! The dandelion can break through any soil and even penetrate cracks in concrete. This plant will usually show its face in heavy, acidic or clay-like soils or healthy, fertile ones.

Wood Sorrel


Sorrel is often mistaken for clover, due to the shape of its leaves and blooms with yellow, white or purple flowers in the spring. Sorrel is also edible and makes for a lovely addition to salads and soups. This plant often shows up in soil that is both highly acidic and clay-like.


Yarrow is a perennial weed with feathery leaves and lovely little white flowers with yellow middles. It’s indigenous to North America and can be quite beautiful in meadows where wildflowers grow freely. However, yarrow also likes to make its home in gardens and due to its hardy nature can be difficult to remove. If you’re finding yarrow in your garden, chances are your soil is hot, dry and low in fertility. This often shows alongside dandelion or plantain.


Crabgrass tends to mean that you’re missing calcium and phosphorus. Soils that produce crabgrass often have very high levels of magnesium, potassium and chlorine and a very low pH level. This grass is difficult to control, so try to keep your gardens and lawns well-watered to prevent it taking hold.


Thistle is a tough one. This weed is aggressive and has one seriously impenetrable root system if it grows too big. If you don’t want thistle to spread in your garden, get it out and quick! Once it flowers, you’ll have new seeds to worry about. Thistle usually grows in soil that is poor and has low fertility—think sandy soil or clays. It often shows up alongside crabgrass and dandelion.


Chickweed is a low, mat-forming plant with a fibrous but shallow root system. It can spread to cover very large areas and is usually found in moist, dense sites in milder autumns and springs. This plant is extra happy in cool, shaded areas. Bonus: Chickweed usually flourishes in healthy, fertile soil with a pH of 6.2 to 7.0. Lucky you!

Have you learned to “read your weeds?” What patterns have you noticed in your gardens? Let us know in the comments!

Originally published for Care2 at: http://www.care2.com/greenliving/what-your-weeds-say-about-your-soil.html