Background Information

• Compost is organic matter that has been decomposed into a product called humus that is used as a soil amendment or organic fertilizer due to its high nutrient content.
• Compost is generally comprised of the greens and the browns. The greens contribute the nitrogen and are generally vegetable scraps and grass clippings. The browns contribute the carbon and are dried leaves, small sticks, cut-up cardboard, and generally anything brown and dry.
• When the greens and browns are mixed together, wetted, left to decompose for long periods of time and occasionally stirred, compost is created!
• Compost is an excellent soil amendment in organic farming and gardening. Compost adds NPK to the soil (Nitrogen, Phosphorous, and Potassium) and helps fruits and vegetables get all of the nutrients they require to grow large and healthy, without added chemical fertilizers.
• Compost is a way of recycling our natural waste. By composting, we are creating a closed loop food cycle. A closed loop food cycle happens when the excess food we produce is not wasted, but added back into the soil that creates more food. Just as we recycle glass, plastic and metal to create new glass, plastic and metal, so too are we recycling food to create more food.

Topics / Goals / Learning Objectives

• To understand what compost is and its role in organic gardening.
• To explore an existing compost bin.
• To contribute to an existing compost bin.
• To understand the relationship between composting and recycling.

Opening

Welcome to the garden! Today we will be reviewing what we learned about composting last week, create our own compost, and learn why compost is so good for our garden beds and vegetables. Who can remember what we learned about compost last week? (Allow time for answers.)

That’s great! Yes, we learned that composting is a way of recycling our food scraps and natural materials in order to grow new food. Compost is comprised of “green” ingredients and “brown” ingredients. What are some examples of the green ingredients? The brown ingredients? (Allow time for answers.)

Now that we know how to make our compost, let’s learn about why compost is so important for our garden! Instead of adding chemical fertilizers to our soil, we add compost, which is an organic fertilizer, and helps our plants grow large and healthy. Compost provides food for our plants. For example, tomatoes are “heavy feeders” meaning that they are very hungry! By adding compost to the soil where we plant tomatoes, we are guaranteeing that there will be plenty of nutritious food for our tomatoes to eat so they can grow up really strong!

After we make our own compost, we’re going to be adding some of our finished compost to your garden bed by digging it throughout the soil. This is called double digging. Let’s begin!

Procedures / Activities

Prep: The students will divide into 3 groups in the garden: one group turning the compost, one group adding new compost, and one group sifting compost. Have a few buckets ready with different ingredients, such as cardboard (to be ripped apart), dried leaves, soil from the garden (hopefully full of worms!), vegetable scraps, etc. Set up stations before bringing the class to the garden. Have shovels, gloves, and compost sifters ready.

1. Welcome students into the garden and have the students sit in a circle.
2. Introduce lesson with the Opening (above).
3. Tell the students that we are now going to split into 3 different groups. With grades K-2, have one teacher/adult lead each station. With grades 3 and above, have one teacher/adult or student leader lead each station. The first group will be using their shovels to stir the compost. The second group will be cooking their own compost stew. The third group will be sifting finished compost to double dig into their bed.
4. After each student in each group has a turn, rotate groups. Continue rotating until each student has participated in each activity. Tell the students to put their tools and gloves away and then gather back in the circle where we began.
5. Ask the students what they observed, experienced, learned, etc. Did anyone see a worm? Why do we love worms in our compost? (Allow time for a discussion and questions and answers.)
6. Before concluding, go over what we’ve learned about compost these past two classes. What are the ingredients? What are the browns and the greens? What does double digging mean? Why do we love worms? How can you compost at home? How can we compost in school? Why do we compost? Allow time for brainstorming.
7. Thank the students for their hard work in the garden. Until next time!

Lesson Resources

CompostStewPartII_Lesson