Composting life cycle

Activity

Learn the different stages of a plant's life cycle and the cyclical nature of composting.

  • Estimated time: 30 minutes
  • Location: Outdoors & Indoors
  • School term: All year round
  • Level of experience: No experience needed
  • Subject(s): Science

Learning objectives

  • Track the journey of a sunflower from sowing to composting

Preparation

It is possible to do this activity by studying existing plants in the school garden. To gain a greater understanding of plant and composting life cycles learners could also grow their own plants from seed, such as sunflowers and lettuce.

Equipment

  • Pencils
  • A compost area to study
  • Plants growing in the garden, at different stages of growth
  • Paper for drawing life cycles

Step by step

  1. Explore the garden and search for plants at different growth stages. Look at the compost heap. Can learners identify any of the ‘ingredients’? Do they look like plants? Is there a sunflower (or other flower) to examine?
  2. Explain that compost is made from organic materials and ask learners to give examples of flowers and vegetables they know. 
  3. Ask learners to draw the life cycle of a plant or flower they know. They may already have experience of sowing seeds and watching them germinate. 
  4. Discussion: What would happen in the garden if a sunflower was growing in the soil and there was no gardener to put it in the compost heap? (It rots down and adds ‘organic matter’ to the soil).
  5. Discussion: Why do gardeners take the trouble to make a compost bin and add all the dead plants, cut grass, leaves etc. rather than letting nature do it for them? (Tidies the garden, makes space for new plants, looking after the heap properly speeds up the composting process).

Hints & tips

  • There is no need to buy a compost bin, simply create a pile of organic material in a corner and cover with a waterproof sheet.
  • Use this activity as part of the Earth Matters class growing topic.