Permaculture Weed Confusion, Part 2

Every garden has weeds and most gardeners hate them - but some think that there's more pros than cons to just letting them run wild. Here's my take on a selection of those arguments.

In part one of this series I defined what weeds are (any unwanted plant that grows without sowing or cultivation in an agricultural or horticultural setting) and then set to providing critique on the first five of ten very common “pro-weed” permaculture maxims (in no particular order). In this article I address the remaining five.

Don’t let the pretty purple flowers, or its nitrogen-fixing properties fool you. Vetch is a tenacious weed that is very difficult to remove from a garden once established.

More things the gurus say - and my take

6. Indicator Plants: Weeds can indicate specific soil conditions or imbalances. Observing which weeds thrive in a certain area can provide insights into the soil's pH, nutrient levels, and other factors.

The problem with this claim is evident in the wording: “weeds can indicate…”. This information has the same value as saying that the sniffles can indicate a cold, or a flu, or a sinus infection, or radiation sickness, etc. In fact, at least a runny nose indicates a problem. Sometimes an indicator plant indicates nothing at all. For example, if one “googles” what dandelions indicate, the 1st response is that, “Dandelions generally indicate poor soil that is low in calcium, as well as compacted”. While it is true that dandelions will grow in poor soil - they will also grow in excellent soil - so just because dandelions are present does not mean that one needs to start amending the soil with calcium carbonate (lime), or that deep tilling is needed, because the presence of dandelions sometimes indicates nothing more than the presence of dandelion seeds. The reality is that many weeds are simply tenacious survivors, so while they can grow in deficient soils, they also grow in excellent soils. While it is true that some indicator plants can provide clues to help diagnose a soil problem, that information is rarely conclusive, and further examination is usually required to achieve certainty, because an indicator is not necessarily a soil test.

7. Edible and Medicinal Plants: Many so-called weeds are actually edible and have medicinal properties.

The fact that a plant might be medicinal or edible does not make it any less of a weed if it is not wanted in a garden. Let’s consider three of the worst weeds I know - Japanese knotweed, goutweed, and bindweed.