Buying soil for veggie beds

Grow healthy soil and you will have healthy vegetables is the motto of many food gardeners, so, when starting a new veggie bed, people want to buy the best soil they can get. Many food gardeners, however, have been disappointed with the quality of soil they bought. The aim of this blog post is to give people a few ways of checking the quality of soils before buying, so they can make the best possible start with their new veggie bed.

Ten Tips and Hints

This month ten tips and hints that may help you make your food garden even better.

Microbes in your soil

In this blog post Letetia Ware explains how to make bokashi, and also a simple fermented liquid, a simple fungi-rich compost and potting soil.  It documents information provided by her during the Food Garden Group's 2016 winter workshop.

And now improve your soil biology

Tasmanians Steve Solomon and Letetia Ware have a lot of expertise in soil biology and creating healthy soils. They have different approaches to it, but we can learn a lot from both. In this blog post I compare their approaches and come to the conclusion that they are really part of one and the same soil biology triangle.

Book review of 'The Intelligent Gardener'

The Intelligent Gardener (Steve Solomon with Erica Reinheimer, New Society Publishers, 2013) is a rare gardening book because it invites readers to broaden their opinion on what organic is and acquire soil-analysis skills that go beyond the repertoire of most experienced food-gardeners.

On page 93 Steve Solomon says 'I wrote this book to function like 'Analysis for Dummies'.  I will tell you only what you absolutely need to know - in the simplest possible terms.  Indeed, a better title for this book would have been 'Soil Science for Dummies', because that is what it is.  It is a clever attempt to convey the very basics of soil science, soil testing, soil analysis and formulation of fertilizer plans to non-professionals who are not afraid to be taken on a big learning curve.  

The book assumes the reader knows nothing about chemistry.  However, as Steve says on page 71, 'soil testing and all that goes with it does not match some personalities. If having a non-scientific personality describes you, using Complete Organic Fertilizer is a parallel approach to soil re-mineralisation that does not require soil testing or precise weighing and spreading of fertilizers.'

Inexperienced gardeners and those who do not wish to learn anything about chemistry might want to read Steve's book Growing Vegetables South of Australia instead.  It is an excellent general-purpose vegie-garden book. The version presently for sale in bookshops contains Steve's latest Complete Organic Fertilizer recipe and all you need to know to produce healthy fruit and vegetables.

On the other hand, if you are an experienced vegetable gardener with a commitment to feed your household on an ongoing basis, then you may learn a great deal from The Intelligent Gardener.  This sentence by Erica Reinheimer at the start of the book (page xiv) may make you interested 'this book uses organic methods, but it widens the scope of organic gardening to include some of the best techniques used by today's certified organic farmers.  The result is better, more productive gardens, more nutritious food, and the best tasting vegetables you have ever eaten.'

In The Intelligent Gardener, after providing evidence that in the 21st century we can do better than 'just compost, manure and mulch', Steve Solomon argues that a standard organic fertilizer mix can only provide what the average garden needs.  He says (page 84) 'no standard complete organic fertilizer can possibly grow food to the degree of nutrient-density that can be achieved from re-mineralisation according to a soil test result.

I will probably have to read this book a number of times before fully grasping its content, but then I would like to sample my garden's soil, have it tested, interpret the results and formulate a complete organic fertilizers specifically tailored to the needs of my garden.

For the analysis part Steve provides worksheets at the end of the book that precisely follow the report you receive back from the test-lab. Erica Reinheimer developed an alternative in the form of an online app named OrganiCalc (see https://growabundant.com/).  After paying a small fee, you simply enter your soil test results in it and it tells you what your tailored complete organic fertilizer should contain.

The aim of this book is to make available to serious vegie-gardeners the opportunity to analyse their soil themselves.  The whole process is simplified by focusing on just one carefully-chosen extraction method (type of test) and the layout of the test report provided by one carefully-chosen US company.  That of course means that (page 100) 'should you attempt to fit the reported levels given by any other extraction method into this book's system, well, the numbers simply won't work.'

It is suggested that there is a small-business opportunity here for people who easily grasp the material covered in this book and are happy to learn more. Page xi says 'The writers hope that some readers, after having learnt how to analyse their own soil, learn enough to become a 'neighbourhood soil analyst', helping gardeners collect soil samples, send them to a lab, analyse the results, and supply and mix the organically approved minerals the soil needs'.

Steve and Erica started a soil analyst cooperative (see http://soilanalyst.org/) that lists registered soil analysts (at present mostly in the USA) and supports those who want to set themselves up to test soils and provide organic fertilizer mixes to other gardeners in their communities.

The book gave me the feeling that it was written first and foremost for American readers, but that does not take away from its relevance to Australia.  If there had been more reference to Australian research, soil conditions and products and if kilograms/10 sq.metre had been used in addition to pounds/acre (lb/ac) then Australian home-gardeners would have felt more 'at home'.

Never before have I seen a gardening book on this subject for non-professionals.  For the right type of reader The Intelligent Gardener may for ever change the way they think about and treat their garden's soil.  It may lead to better organic practices and most-importantly result in more nutrient-rich organic food.

Soils ain't soils

There is an incredible difference between soils in Tasmania and soils in, for instance, river deltas like the Nile delta or Bangladesh where regular floods refresh and replenish the land at least once a year.  An island like Java has young incredibly fertile soils because of regular volcanic activity.

In comparison, Tasmania has very old soils that have provided nutrition to native vegetation for millennia and have been subject to leaching and other weather influences for a very long time.

Tasmanian gardeners may believe that adding compost, manure and blood and bone to their garden is all that is needed to provide the nutrition their food crops need, but let's consider this for a moment.

The compost you use is most likely to come from your own garden.  Elements and trace elements that healthy food crops need and that come in the form of zinc, magnesium, potassium, iodine, iron etc. etc. in your soil, will not be added to your soil as compost if they were not in your garden soil in the first place because plants use these elements if they are in the soil, but they do not manufacture them. 

Manure from Tasmanian sheep or cattle is also unlikely to have sufficient quantities of these elements because they would be lacking in the soil the sheep or cattle graze on.

Blood and bone produced in Tasmania or on the mainland most likely will also not have enough of them either, because there will be insufficient quantities of them is the soils and therefore the animals.

Steve Solomon discusses these issues in his book Growing Vegetables South of Australia.  It is not the easiest of reads at times, but it is a very good guide for Tasmanian food-gardeners, as it is specifically written for Tasmanian soil and climate conditions.

Steve Solomon argues that the only way we can make our food crops really healthy and therefore optimally nutritious is to use a 'complete organic fertilizer'.  Based on years of experience he provides a number of options and choices.  I took his advice and began to use my own mix based on his recommendations.  I am in no doubt that this has made a big difference to the health of my crops.

Here are the ingredients and quantities of the complete organic fertiliser I use:
Blood and bone 1, Lime 1/2, Kelp 1/2, Dolomite 1/2, Seedmeal 3

The result is this:

I got myself six large tubs, 5 for the ingredients, and one for the mix.  I wrote the quantity on the lid of each tub because I can never remember the formula.  With a measuring can I put each ingredient in the mixing tub and then mix well.  The mix is a potent one.  I do not use it liberally everywhere all the time.

In my garden I use a 3-year crop rotation (Legumes, then Leaves, then Roots).  I apply a little bit of the mix before sowing my Legumes, a lot when sowing/planting my Leave crops and nothing at all when sowing root vegetables.

Ingredients such as kelp are not necessarily cheap or easy to get, and, as usual, the bigger the quantity you buy, the more cost-effective it becomes.  I realise you may wish to try this before buying too much, but buying small quantities is not very economic.  Hardware stores and nurseries sell some of the ingredients.  The Roberts store near the ABC roundabout has some ingredients.  Hollander Imports along the Brooker Highway (opposite TAFE) is, in my opinion, a really good supplier with competitive prices.

In his book Steve Solomon is not afraid to give his opinion about things.  He argues, for instance, that improving sandy soils is 'doable', but improving heavy clay soils is not worth the years and effort it takes.  Well, I chose not to believe him when I tried to work with a heavy clay soil in part of my garden.  I gave up after nine years and brought in good soil from elsewhere.

Google 'Steve Solomon gardening' and you will find a lot more information on this subject.  There is even a YouTube video. The book is available at good bookshops in Hobart.

In conclusion I like to say 'soils ain't soils'.  We can not all expect to grow the same things with the same rate of success because our soils are not the same.  Making sure that our fertilizers contain what plants need is the way to success.

Testing the pH of your soil

The pH value of your soil tells you how acid or alkaline your soil is.

The pH scale runs from 1 (extreme acidity) to 14 (extreme alkalinity).

It's important to know the pH of your soil because your plants won't be able to acces all the nutrients that are available in your soil if you don't have the correct pH. Different plants, require a different pH, but many vegetables are happy in a soil with a pH between 6 and 7.

How do you test the pH of your soil?

1.You can buy a soil pH test kit from your local garden centre.


You have to place a level teaspoon of mixed soil from your garden on the test plate, add a few drops of the indicator liquid and stir. You then dust the paste with the white powder from the kit and wait one minute.

Compare the colour of your soil with the colour card provided to find out what the pH of your soil is.

This method works but I find it sometimes a bit hard to determine the matching colour from the colour card. But that might just be me.

2. Another method is checking the pH of your soil with a digital soil pH meter.


You take a sample of your soil (2 cups) and mix it with the same amount of water. You have to compact the soil and drain of the excess water. You can then push the probe in the soil, wait for 60 seconds and note the reading.

I find the digital meter easier to use then the test kit. The digital meter comes with instruction on how to use the meter and a pH preference list for flowers, trees, shurbs, fruit, vegetables and herbs.

The test kit and digital meter are roughly the same price ($20-$25).

Which ever method you use, it's important that you don't rely on just one reading. It's important to test several samples from different parts of your garden bed.

Once you know the pH of your soil, you can for example add lime to raise the pH and compost to lower the pH of your soil.