No one sets out to do more harm than good, but guerrilla gardening can have hidden pitfalls... Don't know your heirloom from your F1? Clueless about the perils of peat? In this guide, ecological grower Poppy Okotcha comes to the rescue, with the essential do's and don'ts of eco-friendly guerrilla gardening.
Maintaining diversity in seed is vital, because diversity = resilience. But, most large seed sellers mass produce a limited number of seed varieties, using industrial, chemical agriculture, with poor human rights observation.
Choose not to support this industry, and safeguard seed diversity by:
Saving seeds from your plants
Swapping seeds with other local growers
Joining a seed library (e.g. Heritage Seed Library)
Choosing to grow heritage, local seed varieties
DON'T buy F1 seed
F1 seed is the result of breeding two seed lines to create progeny with certain traits. While this can be useful, seed saved from F1 plants (or F1 plants that self-seed) will give a daughter plant that doesn’t resemble the parent plants, and will generally be very poor quality.
By not sowing F1, you'll be able to save your seeds (or let the plants self seed), meaning you won’t have to buy seeds for that plant ever again!
DO grow heirloom/heritage seed
Heirloom and heritage seed is seed that can be traced back, having been grown, saved and passed down for many generations (usually 50 years) within a family, community, region or project. This can offer brilliant adaption to local growing conditions and huge genetic diversity. Heritage seed has often been bred for better flavour and nutrient density over aesthetics and high productivity. Heirloom and heritage seeds are open-pollinated.
DO choose open-pollinated
Open-pollinated seed produces plants that can be pollinated by a natural mechanism, such as self-pollination, insects, birds, the wind – or even a human with a paintbrush! Generally, their progeny will be like the parent plants, with some natural, healthy variation. This makes them great for seed saving.
DON'T plant invasive species
Sometimes species that aren’t native to an area, once introduced to it, can unbalance the local ecosystem. These so-called "invasive species" outcompete other plants in the area or spread disease, and so endanger local plant and animal species.
Species aren't inherently invasive. Rather, they become invasive as a result of some other force (usually human meddling), such as rapid environmental changes or being moved to a new area.
Most countries (or regions) have a list of invasive species which it is illegal to plant or propagate. Check what's invasive where you live, and avoid planting it.
DO sow native, local meadow mixes
If you choose to grow a meadow, have a little search for a meadow mix that is "native", meaning from your local area. These grasses and wildflowers are well suited to your area's conditions and so will thrive in the local environment, while supporting the other life forms in the ecosystem that are adapted to them.
DO use plants that will add fertility
Plant dynamic nutrient accumulators, such as comfrey and alkanet. These are plants that bring nutrients up from deep in the soil – out of reach for many plants – which they store in their leaves and eventually return to the soil surface as the leaves rot down.
Muddle legumes in throughout. These are plants in the pea family such as beans, vetch, clover – they’ll fix nitrogen into the soil.
DO choose plants for wildlife
Think of wildlife as gardening assistance; they help keep the space healthy. They can: aid in pollination; act as a natural, chemical-free pest control; provide fertilisation; improve soil health; and support ecological balance.
Earthworms, toads and frogs, birds, bats, butterflies, bees and ladybirds are all great garden assistants. And, of course, supporting biodiversity is a great thing to do in itself!
DO identify and research “weeds” before you remove them
Many common “weeds” are actually brilliant medicinal, edible, habitat and pollinator plants, that condition the soil. Before removing all the green in sight, try to ID the plants. Ask a friend, use an app (“LeafSnap” is free!) or a handbook. Find out what they offer the space and see what they look like through the seasons – they might have wonderful flowers later in the year. Keep as many “weeds” as you can.
DO plant plants that the community will benefit from
Consider plants that other people will benefit from. They may smell good, look wonderful, be edible, or have medicinal properties. Remember, guerrilla gardening is reclaiming public space for public good – your garden has the power to benefit everyone in the area in some way.
DO focus on diversity
Diversity=resilience, so try out "companion planting" in polycultures. This is selecting a range of plants that get along well together, supporting each other’s growth. Possibly the most well-known are the "Three Sisters" grouped by the Iroquois, Cherokee, and other Native American tribes.
DON'T use peat compost
Peat comes from peat bogs: precious, finite, ancient habitats that sequester tons of carbon. Mining peat for compost releases CO2 into the atmosphere and destroys valuable ecosystems, including many of the rare and endangered species that live in and around ancient peat bogs. So, look for compost labelled "peat free".
DO make your own compost
To me, there’s no better way to connect with the natural world and its rhythms than through the alchemy of composting. It’s mucky, mysterious, and transforms potentially pollutant waste into an incredibly valuable resource. I almost get more excited watching waste turn to compost than seeing a seed germinate!
There are many ways to compost, but my favourite is worm composting, or vermicomposting, which harnesses red worms’ incredible ability to munch through pretty much any organic material.
DO test manure before spreading
Aminopyralid is a broad leaf herbicide used to kill “weeds” in hay fields. The hay is fed to livestock (e.g. horses and cows), they poop it out, and the aminopyralid stays in tact. As it spreads on a growing space, any broad-leafed plants (not grasses) will become sick and slowly die.
Either avoid using manure full stop, or test before spreading. Plant a couple of broad beans in the manure and others in compost. Wait for them to grow. If it is contaminated with herbicide, the leaves of the manure-grown beans will develop deformed (you can use the others for comparison).
DO build the soil
The soil is the foundation for a healthy grow space. Check the condition of your soil. If the soil is compacted, grow pants like mustard with roots that will help break it up.
Add organic matter – mulch – to improve soil condition and keep the sun's rays off it (bare soil is a wound in the Earth!)
DO mulch with organic matter
Mulch is a material that is spread on the surface of the soil. You can use unlaminated cardboard, newspaper, compost, leaves, wood chips, well-rotted manure, wool carpet, or even old cotton curtains.
Mulch will protect the soil surface (ensuring the structure of the soil is hospitable for the precious soil life), insulate, and reduce evaporation (meaning less watering). Ultimately, it will rot down, feeding the soil life and your plants.
DO try “no-dig”
This is a way of growing that disturbs the soil least and so maintains healthy soil life. It also means no back-breaking digging.
DON'T use chemicals
Chemicals used on growing spaces may temporarily solve one problem, but in the long run destabilise ecosystems, causing long-term issues, and often ultimately chemical dependence. They’re also expensive and often toxic to us too!
Instead of relying on chemical "fixes", focus on creating a diverse space (lots of different plants) with healthy soil. Healthy plants aren't bothered by disease as much, and natural predators should take care of any pests. For example, plant flowers like yarrow and fennel: hover-flies love them, and their larvae eat aphids. No pesticides needed!
DO use organic everything (if you can)
Organic seed, compost, plant feeds! While 'organic' often sounds like the more expensive option, as you build an organic practice, you become more self-sustaining – being able to seed save, keep off pests and feed the soil with no external things needed – ultimately saving money in the long run.
DO respect what’s already there
Ideally, choose a spot that you’ve seen through all the seasons. That way you can work with the site and make changes with sensitivity to what is already there (misunderstood "weeds" included) and which creatures may already call it home.
DO reuse rainwater
If you can, funnel rainwater to your garden plot, or capture it in barrels to use later. This will help reduce your garden's consumption of water, precious resource.
Check out Dream Green's C.L.A.S.H. manifesto to see how eco-friendliness is dug into our philosophy. If you want more tips on sustainable, regenerative guerrilla gardening (from sourcing second hand, to understanding invasive species) get the handbook.
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