Children love gardening, and learning about soil is a great way to get them involved.
Learning about soil involves digging and getting their hands dirty.
Working with soil helps connect children to Papatūānuku
As teachers we can support them in their interest if we know about soil too. We all know that plants need soil to grow, but is our soil healthy and will it support our plants to grow strong?
Soil is not just dirt; it is a lively ecosystem of micro-organisms that decompse organic material and turn it into humus-rich goodness that our plants need to grow healthy and strong. The micro-organisms need the right temperature, moisture levels, acidity and air in the soil so they can go to work. In return our soil becomes healthy and is able to breathe, recycle waste, provide support and nourishment for plants, shelter seeds, store nutrients and cleanse water.
As gardeners, it is up to us to ensure that our soil remains healthy so it can supply nutrients to the plants we grow and creatures that live in it. Soil is made up of many things including sand, clay, organic matter, microscopic organisms, worms and insects. It is 25% air, 25% water, 45% earth (clay, silt and sand), and 5% organic matter.
If the soil has a lot of sand in it then water will drain away quickly and the soil will dry out. Soil with a lot of clay in it is the opposite. Water doesn’t easily drain away and the soil becomes a solid lump in summer and a soggy bog in winter. Both types of soil can become more productive with the addition of lots of organic matter, such as compost and aged manure. Compost will help add moisture and nutrients to sandy soil, and will eventually help clay soil break down the lumps,helping it to drain more freely, and add nutrients.
The plants that grow in the garden, be they vegetables, flowers or weeds, all take up nutrients from the soil which depletes it of its goodness. As gardeners we need to ensure that we help the soil by replacing those nutrients. There are a number of ways to do this:
- Add lots of compost, which is made up of decayed green waste (eg lawn clippings, food scraps, weeds that have not gone to seed) and brown waste (eg fallen leaves, shredded newspaper or cardboard, manure)
- Dig in decomposed manure - never use dog or cat manure as they contain harmful toxins
- Use liquid fertilisers feed the plants. Liquid manure can be made from seaweed, manure or worm tea
- During late autumn/winter when there is not much growing in the garden, sow a ‘green’ crop of plants such as lupins, mustard and buckwheat. All of these are high in nitrogen and will add this important element back into the soil through their roots and decaying leaves once they have been dug into the soil about six weeks after germination
- Practice crop rotation so the same plants are not grown in the same place year after year
Learning about soil is a great way for children to build their observational skills. Healthy soil will be full of living creatures from things you can easily see like plants, worms and insects to tiny microscopic organisms like fungi and bacteria.
The key to any successful garden is the soil that is home to the plants. Learning about the soil in our gardens, the type of soil that different plants like to grow in and how to maintain those conditions will lead to healthier and strong vegetable crops and flower beds, that are more resistant to pests and diseases.
If you have enjoyed this blog post, why not see my post titled Keeping Children Safe While Gardening, where I discuss a range of considerations around health and safety when gardening with young children.
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