Name of activity:
Double digging and Composting
Activity written by:
Santa Fe Elementary teachers in the Math and Science in the Outdoor Classroom
Latex Gloves or gardener's gloves, Shovels, Garden forks, Rakes, Watch,
Whistle, Scrub brush for cleaning tools, boards to stand on while double
digging, hose and key if needed for water faucet, use a shaded area for the
compost, straw, winter vegetation or leaves or compost from a grocery, Soil
enrichment (manure, compost, plant vetch, sea bird guano, or kelp),
twigs-stalks-small branches for under the compost pile, soil from double
digging exercise, buckets/wheel barrow, gloves
What are things we can do that will positively affect the quality of soil in a
Teachers/leaders should demonstrate the proper way to to carry and handle
tools. Tools carried blade down. No over the head chopping with rake.
When students have finished with a tool, they should put the tool in a
designated area where it will not interfere with students' movements.
Composting materials and soil must be carefully spread on the mound and not
thrown. No jumping or kicking any of the materials.
The hose is only used for watering the compost pile and cleaning tools.
a. There will be two activities happening simultaneously,
composting and double digging. Meet as a whole group to demonstrate the
proper ways to handle shovels, rakes, and other tools. Demonstrate the proper
way to dig. Refer to John Jeavons book, How to Grow More Vegetables.
a. Find a shaded area near the garden to begin your compost pile. Start by
loosening the soil in the area you have chosen. Water thoroughly.
a. Have the students put on their gloves. Get sticks etc. for the
first layer from the arroyo. The first layer of materials is made up of twigs,
small branches, corn and sunflower stalks. This part of the composting can
be done with the whole group. Then put water on the sticks. Water will be
added to each layer. Then add equal amounts of straw and soil.
a. The next layer is made up of straw. Water the pile.
a. Then add the green vegetation using gloves. Water again.
a. Then add a bucket of soil to inoculate the pile with
microorganisms. Add water. After this you start with the straw again. Continue
with these three (4a-6a) until the pile is 4 feet tall by approximately 4 feet
a. The pile needs to be watered at least once a week if no rain or
snow falls. If the pile is not turned, it will take up to 8 months depending on
temperature, moisture and contents of the compost.
b. Divide the group into two. Have half of the group continue with
the composting. The other half will be double digging.
b. Start at one end of your garden plot. (5 x 20 is a good size.
Be sure that the soil is moist enough that the shovel can go into it. Try this
a week ahead of time. Add water daily until the soil is pliable.)
b. Dig a trench across the width of the bed standing on a board to
prevent compaction. (See activity called compaction.) The trench should be
about one foot deep and one foot wide. (If less because the soil is too hard,
that's OK.) The soil from the first row can be put in buckets or a wheel barrow
to be used in the last trench or for the compost pile. See John Jeavons book,
How to Grow More Vegetables for more information.
b. Place a garden fork (stronger than a pitch fork) at right angle
to the trench and try to pierce the soil as deep as you can. While one foot is
on the shoulder of the fork, wiggle the pitch fork back and forth to loosen and
fluff up the soil.
b. Dig another trench, but put the soil in the first trench this
time. Continue until your whole bed has been completed- dig with shovel,
loosen with fork.
b. Use soil in buckets/wheelbarrow to fill in last trench.
b. Even out the bed by raking it.
b. Add minerals (kelp, sea bird guano) or winter-spring vegetation
seeds (vetch, rye) by following the package directions. If not planting
vegetation, collect leaves to cover the garden and prevent erosion. If you are
planting spring vegetables, be sure it is after the last frost. If possible,
transplant small plants started in the classroom. See John Jeavons' book How to
Grow More Vegetables to find optimum spacing for each vegetable.
c. Rotate the groups from composting to digging according to how
many tools and how much time you have. Be sure you have plenty of adult or high
c. Ask the students while they are digging if they see a
difference in the soil that they dug. Ask them why that helps the garden.
c. Ask the students while they are composting why they think they
are composting and how that will help the garden.
c. Monitor the students digging techniques and tool usage.
c. Remind students who are composting to layer straw, water, green
vegetation/kitchen waste, water, soil, water, and then back to straw.
c. When both activities are complete make sure the students
properly clean and put away all supplies.
Students will be able to describe the elements of quality soil.
Students will be able to list the ways you can maintain and enhance quality