Phoenix Gardening Course – Sow & Grow. Chapter 3

Here’s the next short chapter in the brilliant Urban Gardening Course series.  Here, Ruth gives an overview on soil and how to support it.  Soil is a vital resource for organic growers: if you support your soil, your plants will thrive.

According to Wikipedia, Soil is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life.   In gardening terms, the organic part of the soil formed when plant material is broken down by microorganisms living in the soil is called humus.

• For organic gardeners, ‘good’ soil is 5%-15% humus.
• Humus binds mineral particles giving the soil a ‘crumb’ structure.  This allows spaces for air and water and is key to the soil’s drainage.
• Humus holds water and nutrients, prevents leaching and makes nutrients available to plants.

Intensive cropping uses up nutrients and humus faster than a ‘natural’ soil (i.e. one that is not being farmed), therefore it is essential to support your soil if you want healthy crops.

Soil & compost life

• Microorganisms & fungi do the ‘hot’ work, before the red brandling worms get going.
• Worm casts contain 5-10 times the amount of nutrients that soil alone holds.
• Plant root hairs uptake of nutrients is facilitated by microorganisms and fungi.

We need to support our soil by keeping it well fed.  We can do this in a number of ways: growing crops, mulching the soil, adding organic matter.  One great way of adding organic matter is by making our own compost from our kitchen scraps and garden waste.

How to make compost

• Choose a suitable container eg: wooden, plastic bin
• Siting of bins: on soil, accessible, tidy, sunny
• Add layers of waste in an equal ratio: ‘Brown’ (such as cardboard, stems of plants) which provide the carbon and ‘Green’ (kitchen scraps, weeds, spent plants) which provide the nitrogen.
• Activators: nettles, wee, horse & chicken dung
• Turning the heap: you can do this to increase the rate of decomposition, but its not necessary
• Compost is ready in 2 months summer, 6 months winter.

Compost some basic dos and don’ts

• Moist (not too wet or dry) & airy.
• Equal amounts of carbon-rich browns (paper, cardboard, brown plant remains) & nitrogen-rich greens (fresh plant remains, raw kitchen scraps).
• No cooked food, meat or fish as this attracts vermin.
• No perennial weed roots or seeding weeds (keep a big bucket or bin full of water to put these nasties in to rot.  You can then add this rotted matter to the compost).
• Keep covered (warmth in, rain out).
• Autumn leaves should be rotted separately.

How to Use your Homemade Compost

• Dig in or spread 1”-2” on surface
• Put in trenches for spuds, runner beans
• Can be spread spring, summer or autumn as an excellent mulch, (as nutrients stable in cold & it protects soil surface from winter)

Join us for the final chapter of the Sow & Grow Course next week which focuses on Pests & Diseases and how to tackle them the organic way.  Check out Sow & Grow Chapter 1 and Chapter 2.