Weeds as Friends (And How To Keep Them Out of your Garden!) - Ultimate Gardeners Cheat Sheet #4

Welcome to the fourth instalment of our Ultimate Garden Cheat-Sheet. I’m taking 10 gardening problems and showing you exactly how we handle them on our flower farm.

Advice from experienced gardeners and traditional gardening books often tell you weeds are the enemy—invaders that must be removed at all costs, often with a heavy dose of weedkiller, as they outcompete plants for nutrients, light and water. But on the farm, we’ve learned to stop reaching for the spray bottle and start listening to what these plants are trying to tell us. These lessons are just as applicable to gardening as they are to farming. When you look at an ecosystem holistically, we realise weeds aren’t "invaders" but nature’s first responders.

The Forest’s Healing Strategy

In a forest ecosystem, whenever a patch of ground is cleared or disturbed, weeds are the first to colonise that bare ground. This is exactly why they pop up the moment you turn or till your soil! Their job is to cover the soil, protecting the soil microbiology from the harsh rays of the sun and heal the "wound" in the earth.

Weeds also prepare the soil for succession—the natural process where short-lived pioneering plants create the conditions for longer-lived, more stable species to move in. They do this by:

• Enhancing soil microbiology.

• Accumulating nutrients from deep in the subsoil.

• Breaking up compaction with powerful roots.

• Preventing erosion by holding the soil together.

• Fixing nitrogen back into the earth.

Weeds are nature's pathway to a forest

A Lesson from Gorse

I recently observed a cleared patch of ground in a local park where Gorse (Ulex europaeus) had completely taken over. In our area, Gorse is considered a nasty invasive weed. However, after a few months, I noticed something amazing: indigenous species were starting to grow right through the middle of the Gorse.

The Gorse was acting as a natural nursery. Its prickly branches protected the young indigenous plants from browsing animals, while its canopy kept the soil moist and created a cool microclimate. Eventually, those indigenous trees grew tall enough to break through the Gorse canopy, soaking up the full sun and began shading the Gorse out. Since Gorse needs full sun to survive, it started to wither and die. It had completed its role in the ecosystem, and was being replaced. I researched this further, and it turns out this "nursery" method is so effective that it has been used to successfully regenerate forests in places like Hinewai Reserve in New Zealand. You can see this incredible process in action in this video.

Mycorrhizal Bridges

Many of the flowers and crops we want to grow rely on symbiotic fungal networks (mycorrhizae) to help them take up water and nutrients. When soil is bare, these fungi can die out. Many common weeds like Ribwort Plantain (Plantago lanceolata) are excellent hosts for these fungi. The benefit is they keep the underground fungal network "plugged in" and active during fallow periods, so your next succession of plants can immediately tap into the system.

Weeds can help restore ecosystems

Weeds as Messengers: Reading Your Soil

Weeds are incredible indicators of what is happening beneath the surface. If you have one dominant weed, it may be because that plant has a specific "superpower", allowing it to thrive where other plants can't. For example, on our property, we had a patch of heavily compacted soil where Paterson’s Curse (Echium plantagineum) was dominating. Because it has a massive taproot, it excels at breaking up soil that is too hard for most other plants.

When I see Paterson’s Curse on our farm, it's a message to check for over-compacted soil.

So, What Do You Do When You See a Weed?

Instead of pulling it out immediately, try to identify its function. Examples:

• Large Taproots: Like Dandelions (Taraxacum officinale) or Paterson’s Curse. Is your soil too compacted?

• Spreading Root Systems: Like Couch Grass (Cynodon dactylon) or Capeweed (Arctotheca calendula). Is your soil too loose or recently tilled?

• Nitrogen Fixers: Like Clover (Trifolium repens). Is your soil low on nitrogen?

Once you’ve identified the "why," you have two options:

1. Leave it to perform its function (Our Preferred Method)

This is the most controversial but often results in the best outcome. The weed is there to play a role. If you leave it, your ecosystem will likely be better off. You may even be able to use the weed as a "nursery" for the next plant to succeed the weed, just like the regeneration project at Hinewai Reserve.

2. Replace the function

If you can’t bring yourself to keep the weed, replace it with a "useful" plant that does the same job. If you have a nitrogen-fixing weed, pull it and plant something like the nitrogen-fixing Broad Bean (Vicia faba) instead. You are still performing the same ecological function, (also with a crop you can harvest!). Another example - we get a lot of blackberry (Rubus spp.) self sowing on our farm, however due to the spikes and spines it isn't practical to let grow. With its taproot and sprawling brambles, Blackberry functions an accumulation species in our climate, so I try replace it with indigenous saltbush (Atriplex spp.) that performs a similar function.

Shifting the Balance: Bacterial vs. Fungal Soils

One of the most fascinating ways weeds help your garden or farm is by shifting the biological "frequency" of your soil. Most common weeds are early-successional plants that thrive in bacterial-dominated soils, typical of ground that has been frequently tilled, dug, or left bare. However, as you allow weeds to grow and eventually die back, they leave behind carbon-rich, woody stalks and stems. This "brown" material is the preferred food source for beneficial fungi.

By leaving this woody biomass on the surface as mulch, you are encouraging your soil to become fungal-dominated. Here is the magic part: most common "pioneer" weeds find fungal-heavy environments much less hospitable. By shifting the soil biology toward a fungal balance, you are essentially advancing the ecosystem beyond their preferred habitat. You're creating a stable, mature environment where your long-lived flowers can flourish while the weeds naturally lose their competitive edge. No-dig gardening is a fantastic way to accelerate this process.

The "Cheat-Sheet" Summary: Weeds

• Stop the Spray: Weeds are healers, not invaders.

• Identify the Role: Are they tap-rooted "miners"? Spreading "soil protectors"? What are the ways this plant is trying to improve your soil?

• Work with Succession: As your soil becomes more fertile and stable through species succession and added organic matter from weeds, the ecosystem will eventually favour your plants over the weeds.

• Redeem or remove: If you do need to remove a weed, replace it with a more palatable plant that performs a similar function to the weed.

  
  

By changing our mindset from "weeding" to "listening," we can build sustainable gardens and farms. Once you stop seeing weeds as a "problem to be solved" and start seeing them as "messengers" and "helpers" to make you a more successful gardener, you may find the presence of weeds a whole lot less stressful. When we support the natural process of succession, our gardens become more fertile, more resilient, and much easier to manage in the long run.