pH Testing - Results

The results of our pH tests around the garden.

The test card we took the readings from.

We started with some of our 'Normal' soil from a pathway in the dog pen...the only area not improved or filled with imported soil (at least by us in the last 15 years):

'Normal' (path) soil pH 8.5 - 9

Compare this with the media in the Wicking Worm Beds:

Wicking Worm Bed media pH 5.5 - 6
This is with added Dolomite this year.

Dolomite pH 8.5 - 9

Worm Casts from the worm farm scored pH 7 - 7.5

Worm Casts pH 7 - 7.5

The improved soil in the Native Bushfood bed that has had compost added came in at:

Native bed soil pH6 - 6.5

The Home made Potting Media I make up came in at:

Potting Media pH6.5

This contains:

Cocoa (Coir) Peat pH6 - 6.5

Commercial Potting Mix pH6 (can vary with each batch)

Sandy Loam pH7.5 from a local source.

Just as an exercise we tested some of Doc's Hydrated Lime he uses in mortar mixes.

Hydrated Lime pH10+ (off the scale)

Many people advise the use of Wood Ash in the garden (but not in SA)...the result was exactly the same as Hydrated Lime...

Wood Ash pH10+ (off the scale)

At the other end of the scale
was Sulphur Powder at pH3.5-4.

There seems to be plenty of information around on how to increase your soil pH ie make it more alkaline but little on how to lower it ie make it more acidic. The continued application of well made compost will help as will making Wicking Worm Beds...but continue to test your soil/growing media each season and adjust them accordingly.

Plants have their specific requirements and the chart below is a guide for knowing which plants prefer acid or alkaline soil conditions. Please click on the image to see it full sized.

Information for this chart from:
Herbs
Fruit trees
Vegetables - Organic Vegetable Gardening by Annette McFarlane.

Some useful links:
Understanding Soil pH
How to: pH testing.