Defeating weeding by eating: Kids and science in the garden – Part 2: Plant adaptations

Struggling to get the kids to weed the garden? Eat them! (The weeds, not the kids.)

This is the second in a series of articles on edible weeds in the garden and using them to teach science lessons. This can be done in a family, in a day-care or school activities, or with any group working with children and gardens.

Almost no one likes to weed. By turning the activity into a science lesson and a snack, weeding can become fun for your group of young people.

The weed we are going to look at today is common purslane (Potulaca oleracea). Some pictures and a description can be found at the University of California’s key to turf weeds.

After you see purslane once, it is fairly easy to identify. But why does purslane look the way it does? Why does any plant look and grow the way it does? Encourage young people to learn about adaptation by asking questions about a plant and making guesses as to why it grows where it does. Adaptation is what allows a plant or animal to survive better than others in a particular place.

Here are a few questions to ask about the purslane. Ask the questions first, and give the young person time to respond before adding your thoughts.

  1. Why does it have the waxy looking skin?
    Perhaps because it helps the plant retain moisture in a dry environment.
  2. Why does it tend to grow on bare ground?
    Perhaps because it is a fast growing plant, and it is one of the first to show up in bare soil
  3. Why does it grow low to the ground?
    It might be to help it spread out and grow under other plants.
    It might help it block out weeds that could grow around it.
  4. Why are the stems so brittle?
  5. Why are the stems reddish?
  6. What would make this plant grow better in this place than other plants?

Purslane is eaten around the globe. While in the United States, it is considered a weed, in other parts of the planet, it is cultivated as a vegetable. The plant is slightly sour and has a good crunch to it. It can be eaten raw, pickled or used in soups and stews where it can work as a thickener. One word of caution: whenever trying a new food for the first time, it is best to only try a small amount to determine if you have an allergic reaction.

Happy weeding!