OBJECTIVE

Students understand the role of plant matter and microorganisms in building healthy soil. Students will be able to plant a cover crop

ESSENTIAL QUESTIONS

How can we build soil?

MATERIALS NEEDED

• Legume plant with roots and nodes
• Cover crop seed
• Cover crop PowerPoint
• Gulf of Mexico ‘Dead Zone’ Map from NOAA to project

PROCEDURE

This lesson could be done in early spring or in the fall.

Introduction:​

Tell your students they are now in charge of one of the garden beds. The plants have been harvested and today we have to figure out what to do with it to prepare it for the spring. In spring we will plant potatoes in it. Use PowerPoint to talk through cover cropping…
-Raise your hand if you’ve heard of a cover crop.
-Think – Pair – Share: from the sound of the words, what could it be?
-Discuss why/how cover crops: fix nitrogen, protect soil from rain/runoff, add
organic matter to the soil, and suppress weeds
When discussing how cover crops fix nitrogen, show students (and let
students touch) an example of a legume with a node for bacteria. If possible, put it under a microscope connected to a screen in the classroom to enlarge it.
-Show map of dead zone in Gulf of Mexico:
Ask: Where in the world is this map? What is this river? What do you think
gets into this river other than water?
Cover cropping is a healthier way to keep nitrogen in the soil. Synthetic nitrogen can
easily wash away with the rain because it’s not held in place. Bacteria and other life in the soil as well as the plant roots hold this nitrogen in place and increase infiltration in the soil, so it can’t run off.
Go over plan and rules for the garden today

Activity:
Plant Cover Crop

Wrap up:

Draw a picture of the legume with roots and nodes. Describe is happening in that node. Why is this process important?

FOLLOW UP & EXTENSIONS

• After the cover crop has grown and you are ready to plant, turn over the overcrop and plant the raised bed.