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Supported by WWF

Guerrilla gardening

Spread wildflowers and encourage wildlife with homemade seed bombs, then share them far and wide.
Plan a session with this activity

You will need

  • Mixing bowls
  • Something to protect surfaces (for example, newspaper or tablecloths)
  • Gardening gloves
  • Meadow flower seeds (or seeds or flower heads collected from the garden)
  • Peat-free compost
  • Powdered clay (found in craft shops)
  • Cups
  • Mixing spoons
  • Aprons
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Before you begin

  • Plan to make your seed bombs during springtime – March and April are the best months to sow wildflowers.
  • Buy a wildflower seed mix. Make sure you use UK-native wildflower seeds. You could also collect seeds or flower heads from wildflowers that have died back when you’re out walking or hiking in late summer or early autumn. You’ll need to dry the seeds on paper and store them in an envelope.
  • You’ll need one or two buckets of peat-free compost (organic is best, if possible). Make sure you have permission to use it.
  • If you can’t get hold of powdered clay, you can use clay-rich soil, as long as you have permission to use it and it’s not sourced from a conservation site. The method’s a little different, so we've included additional instructions.
  • Cover a flat surface with newspaper (or a washable tablecloth) and set out all the equipment you’ll need.
  • Young people are likely to get messy due to the powdered clay, so kit them out with aprons and set up a hand washing station.
  • The seed bombs will take a while to dry, so it’s best to do this activity over two or more sessions. Once they’re dry, they can be kept in a cool, dry, dark place until you’re ready to use them.

Safety checklist

Use the Safety checklist to help you plan and risk assess your activity.  Additional coronavirus-related controls to think about may include: 

  • Set up a hand washing station that you can use throughout the session.
  • Make sure people wash their hands before and after using any shared equipment or resources.
  • Clean any equipment between different people using it.
  • Remind everyone to stay a safe distance apart at all times. If it works better for you, you could do this activity individually, rather than in groups.

Talk nature

  1. Everyone in the group should talk about why wildflowers are important.
  1. Everyone should choose an area to ‘seed bomb’.

Craft a seed bomb

  1. Separate into groups of around four to six – each group should make one portion of seed mix.
  2. Each group should mix together one cup of seeds with five cups of peat-free compost and two or three cups of clay powder.
  3. Slowly mix in water until everything sticks together.
  4. Roll the mixture into firm golf ball-sized balls.
  5. Groups should place the balls on newspaper and dry in a warm place.

Throw the seed bombs

  1. Everyone should gather in their wildflower space – together, they should throw the seed bombs with enough force to burst and scatter them on the ground.
  1. When summer arrives, wait and see what grows.

This activity helps contribute towards some of the UN's Sustainable Development Goals. Find out more about the SDGs, and how Scouts across the world are getting involved.


This activity gave people an opportunity to show how much they value the outdoors. Seed bombs are one way to help wildlife by creating thriving habitats. Can anyone think of other ways to help local wildlife? People may think about building bird houses, bird baths, butterfly feeders or bug hotels. Can anyone think of things that harm wildlife and their habitats? People could think about litter or pollution. What can people do to help reduce the challenges wildlife faces?

The activity also gave people a chance to help their communities. How did planting seed bombs help others in the community? People could think about how having nice, wildlife-friendly spaces boosts wellbeing. How did people get others in the community involved in their seed bomb project?


All activities must be safely managed. Use the safety checklist to help you plan and risk assess your activity. Do a risk assessment and take appropriate steps to reduce risk. Always get approval for the activity and have suitable supervision and an InTouch process.

Gardening and nature

Everyone must wash their hands after the activity has finished. Wear gloves if needed. Explain how to safely use equipment and set clear boundaries so everyone knows what’s allowed.