Surprisingly, it's not just particular plants that are illegal. The act of planting can be as well.

Founder of guerrilagardening.org, Richard Reynolds has popularized "guerrilla gardening," cultivating plants in places where one doesn't have permission, in the last few years. In the UK, Reynolds was nearly arrested for trying to make a public area a place for plants.

Guerrilla gardening has usually referred to the beautification of public spaces without the permission of the municipalities that own them. This trend has been sourced back to the 1970s and Liz Christy, who would plant all sort of flowers and greenery where she lived in Manhattan.

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Today, the movement continues all over the world. The simple act of planting food, flowers or foliage has encouraged people from London to Los Angeles to bring more natural beauty, food and/or sustainability to their surroundings.

Note: The practice may be illegal in many places, including otherwise public spaces. You could face a fine or worse for planting without permission.

This cute idea is great for stairwells or places where planting in the ground isn't possible.

A great way to repurpose old shoes — if you drill holes at the bottom, the plants still have drainage.

Moss is a great idea for guerrilla gardening because it requires little maintain. Upcycled planters are perfect for taking something old and making it new.

New York could seriously benefit from taking leftover phone booths and turning them into homes for plants. This kind of idea for guerrilla gardening is truly represents what the movement tries to do: repurpose and make new.

This miniature garden was done in a small patch of dirt. Potholes work, too. Unused spaces such at these just need some TLC.

6. Moss Graffiti

Way better for the planet than aerosol paints, here's a recipe on how to make your own moss "paint" to decorate walls or sidewalks.

This flyer box has new purpose and looks a lot nicer than a former empty bin.

The seed bomb idea was created by Christy who used to make her own and thrown them over into abandoned lots. The idea is to provide the materials and let nature take its course; the plants should grow for themselves. You can DIY your own or buy them here.

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