Understanding weeds: life cycle

Time Allocation: 30-40 minutes*

Activity Level: Moderate


Weeds can look like any other plant, and can often even look very attractive.

However, a weed is a plant that grows where it is not wanted, and they are very successful in their reproduction. Learning about the life cycle of weeds can help us control and manage their spread, and understand the impact they have in the local environment.

*Time allocation will be dependent on site selection and travel time.


  • First-aid kit, sunscreen, protective footwear, allergy plans
  • Weather appropriate attired and accessories: hat, sunglasses, insect repellent or raincoat
  • Printable activity sheet
  • Pencils
  • Clipboards (optional)
  • Instructions

    STEP 1

    Tuning in

    Take your group to the site selected to look at the flowering plants around you.

    Discuss how flowering plant life cycles work from germination to flowering; with successful pollination leading to the creation of seeds in fruits. Look at plant features such as leaves, roots, flowers, nuts, fruits and seeds in their life cycle, and discuss why it might be successful.

    Weeds are plants that grow where they are not wanted. Discuss how some flowering plants can be very successful weeds because they produce lots of seed, grow and spread very quickly. Weeds can have a variety of growth forms. This can include grass, tree, shrub, climbers, succulents and bulbs.

    STEP 2

    Delving deeper

    What do we need to know about weeds?

    Can you name any weeds?

    What questions do we still have? Discuss and brainstorm in groups.

    Using the activity sheet, talk through the life cycle of the Blackberry plant (shrub).

    Discuss what the plant would look like through their lifecycle and ask the children to match this the diagram with the life cycle stage.

    It helps to understand the specific features of the plant to learn ways weeds spread from seed into parks, gardens, paddocks and bushland in your area

    Discuss the role that birds and animals play in dispersing the seed by eating the fruit and using the plant as habitat.

    Why do you think weeds are a problem in the community?

    STEP 3

    Honing in

    To understand more about weeds, explore a digital or printed guide to help you. We have several listed in the reference list and recommend the visual stories about pest plants from EnviroStories as a great introduction.

    Research more information about two weeds and look at their life cycle, their seeds and fruits, how their seeds are spread (dispersed) and what problems they cause.

    Are there experts who can help with your investigations? Connect with your local Landcare group, parks, Indigenous Elders, council, groundsperson, gardeners or other weed experts to help you. Their wealth of knowledge and experience is valuable to increase knowledge in this important environmental and agricultural issue.

    STEP 4

    Processing and applying learning

    What have you learnt about the life cycle of the weeds you have studied?

    How can this help in the fight to get rid of these weeds?

    What actions might you take to reduce the impact of such weeds?

    Extension Activity

    Come up with a strategy to remove weeds that you explored in this activity.

    Use online resources or field guides to research a weed and create your own information sheet.