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Our Projects

In partnership with communities, organisations, and sponsors, we undertake projects that benefit growers

Project - MidCoast Growers' Guide

Background to the Guide
The MidCoast Growers’ Guide: Building Resilience to a Changing Climate is a resource for home and community gardeners in the MidCoast Local Government Area (LGA). The resource may also be of interest to nurseries, market gardeners and horticulturalists, as well as to the general public.

The Guide, presented serially in eight parts, provides topical, useful, and locally relevant information and ideas to better deal with climate change impacts that affect gardening and small-scale food production at the local level. MidCoast Growers Network is grateful for support provided by MidCoast Council to undertake the work required to research and draft this resource. We hope that it will stimulate conversation and support growers in their ongoing quest for solutions to common problems.

MidCoast Growers Network is grateful for support provided by MidCoast Council to undertake the work required to research and draft this resource. The Guide links into and builds on the Scraps to Soil program, a NSW Department of Planning, Industry and Environment ‘Waste Less, Recycle More’ initiative that is funded from the waste levy. ​

Part 3 - Why focus on climate resilience?
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As are many other people, growers are taking stock of the effects of shifting weather patterns between and within the seasons:
The climate is getting warmer and climate scientists predict that many parts of Australia will become drier. The most commonly agreed prediction is for an escalation of storms and an increase in the intensity of rainfall, even possibly in areas where the total rainfall will decline. Warnings of climate change are too consistent to ignore, so garden planning must take them into account. [1]

Growers have the additional advantage of being able to witness first-hand the effects of climate change on the plants and animals they care for, and on the animals that visit. All of those who work with the soil work on finding solutions to problems such as rainfall variability, severe winds, and extremes of temperature.

You are sure to have done lots of reading yourself up to now, and hopefully what we have here can contribute to your knowledge and encourage you to read further.

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Greens (photo: Daintry Gerrand)
Climate change and its impacts

The climate change we’re currently experiencing is ‘an alteration in the composition of the global atmosphere that is in addition to natural climate variability observed over comparable time periods and created predominantly by burning fossil fuels, which add heat-trapping gases to Earth’s atmosphere’[2].

Put differently, ‘as more greenhouse gases are added to the Earth’s atmosphere, more of the sun’s heat is trapped. This causes the Earth’s average temperature to rise’ [3].

Important heat-trapping gases are carbon dioxide, water vapour, and methane. In addition to the burning of fossil fuels, emissions from human activities such as agriculture also contribute to this increasingly efficient greenhouse effect.

Climate change makes hot days hotter, and heatwaves longer and more frequent. The number of hot days (> 35°C) or very hot days (> 40°C) per year in Australia has been increasing since 1950 [4]. 

The increased warmth is set to exacerbate the natural variability in seasonal and regional climatic conditions. For New South Wales, this means an increase in the frequency and severity of heatwaves, and more powerful storms, droughts, floods and bushfires. All of these will make it more difficult to manage landscapes and ecosystems [5].

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The Midcoast region was badly affected by the Black Summer bushfires of 2019-2020 (Photo: Gayle Freeland)
Table 1 presents key predicted changes in climatic conditions for the North Coast region of NSW, of which the MidCoast LGA forms the most southerly part. The source is (click on link) NSW Government Office of Environment and Heritage (2014) [7]. The measurements reflect the middle range of predictions generated through 12 separate climate models. The data are presented as:
  • Climatic condition
  • Predictions for the near future (2020-2039)
  • Predictions for the far future (2060-2079)
Please note that all predictions are compared to a ‘baseline’ climate that is calculated on the basis of measurements taken from 1990 to 2009.
Maximum temperature
increase by 0.7°C (near future)
increase by 1.9°C (far future)

Minimum temperature
Increase by 0.7°C (near future)
increase by 2.0°C (far future)

Hot days (> 35°C) per year
13 days (3 days above baseline) (near future)
19 days (9 days above baseline) (far future)

Cold nights per year below 2°C
4 fewer cold nights (near future)
8 fewer cold nights (far future)

Autumn and spring rainfall
7 out of 12 models agree that autumn and spring rainfall will increase (near future)
9 out of 12 models agree that autumn and spring rainfall will increase (far future)

Winter rainfall
8 out of 12 models agree that winter rainfall will decrease (near future)
7 out of 12 models agree that winter rainfall will decrease (far future)

Summer rainfall
7 out of 10 models predict a decrease in summer rainfall (near future)
9 out of 12 models predict an increase in summer rainfall (far future)

Forest Fire Danger Index (FFDI) values [6]
Increase in ‘severe’ and ‘average’ FFDI values in spring and summer; slight decreases in fire weather in autumn (near future)
Both ‘severe’ and ‘average’ FFDI are projected to increase (far future)

As evident from these model-based projections, the already variable climate of NSW is predicted to alter to such an extent that past models for guiding agricultural and horticultural practices will become less reliable. In particular [8]:
  • Plants may benefit from warmer conditions and higher carbon dioxide levels, but will be vulnerable due to more variable rainfall. Increased drought and bushfires will lead to a decline in productivity.
  • There will be less winter chilling for fruit and nuts, and a potential increase in the distribution and abundance of some exotic weeds.
  • Some pests are likely to migrate southwards.
It is also noteworthy that the changes to temperature and rainfall are predicted to firm up as the decades go by, with the climate for the MidCoast by the 2070s on path to being quite unfamiliar to us.
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Declaration by MidCoast Council: Climate Change and the MidCoast [link]
 
MidCoast Council recognises a state of climate emergency exists, with the elected Councillors declaring a climate emergency in October 2019 [link]. In declaring a state of climate emergency, Council affirmed that urgent action is required by all levels of government to take clear steps to avert a climate crisis.

This declaration recognises our commitment to mitigating the impacts of climate change over a number of years. It also recognises the responsibility of all government, including local councils, to reduce carbon emissions and help our communities adapt to the impacts of climate change.

We need to plan for the unavoidable impacts of climate change, especially the risk of inundation of low-lying areas, accelerated coastal erosion, the reduction in annual rainfall, stream flow and water supply. To do this we are developing a risk-based Climate Change Policy and Action Plan, to both manage and reduce our greenhouse emissions, and adapt our practices to reduce our impact on the environment and our communities.

Gardens in a warming climate
Gardening in the 20th century was largely about civic beautification. In the 21st century, gardening has an additional role to play in helping communities build resilience in rapidly changing times. Most of the land in urban areas is privately owned, and the green infrastructure gardeners create on their properties links with other gardens to create corridors in and between communities [11]. Collectively, gardeners can have a huge ecological impact.

Temperature averages and ranges are shifting. Observed increases in frost-free season length and changes in hardiness zones have gardeners questioning how confidently they can rely on frameworks that have historically provided the foundation for planning and achieving gardening success [12]. More than ever, gardeners face the consequences of an increasing number of extreme weather events, and the increasing strength of those events. These include prolonged periods of excessively warm temperatures, drought, heavy downpours, and floods [13].
 
Challenges for growing in a warming climate emerge in four key ways [14]:
  • temperature
  • rainfall
  • bushfires
  • pollinators
Temperature
Longer and more severe heat waves are likely to be more common in keeping with the temperature increases discussed in Table 1 (above). Intense heat can cause heat stress and sunburn to plants. Especially for annuals, it can lead to premature bolting, and to reduced yields due to increased evaporation and loss of soil moisture. Warmer winters mean less frost, making it more difficult for crops like apples and stone fruit to set. It also means that many insects remain active, leading to potentially greater pest issues for gardeners. [15]

Rainfall
Droughts are expected to increase in occurrence and severity across much of Australia. At the same time, extreme rainfall events (heavy downpours in a short period of time) are also expected to increase.

This variability makes the capturing and storing of rainwater more difficult than would be the case with more regular, but less intense, rainfall. It also makes rainfall capture and storage even more important as a strategy.

Since most vegetable and fruit plants need regular watering to produce well, water scarcity will be a challenge for gardeners. There is also potential for flooding and waterlogging in the wrong part of the growing season for some crops [16].

Bushfires
The risk of bushfires is exacerbated by drought, dry fuels and soils, and heat. All of these factors have been ‘aggravated by climate change’ [17].

Drought makes vegetation more flammable and more likely to support extreme fire behaviour and spot fires; and additional heat makes it easier for sparks to take hold. Climate change is lengthening the bushfire season, leaving less time for hazard reduction burning [18].

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Pollinators
Warming temperatures may create a mismatch in timing that disrupts current pollination relationships.

Changing temperatures are resulting in plants flowering at different times than they have in the past, which impacts the pollination patterns of key species like bees[19].

The effects of increased temperatures on pollinator-plant relationships continue to be researched, for example the effect of heat on the structure, colour and scent of flowers, all of which are ‘critical cues in attracting pollinators’[20].

Climate resilience

Resilience refers to ‘the capacity of a system to react to disturbances by restructuring in such a way that its capacity for maintaining key functional processes is upheld. Resilience implies transformative capacity and active capacity building’ [21]. This suggests that it is not only the garden that is robust and that it can ‘bounce back' from adversity, but also that gardeners are resilient as individuals and as a collective.

Resilient gardeners are informed, are open to learning – especially if it is experiential learning – and are connected with other gardeners and to their local communities.
 
One strategy for resilient gardening is to intentionally observe and record changes, and to notice the relationships among those changes. In this way, we can track the elements and complexity of our gardens, and how they interact with other systems, such as the climate and weather systems:
‘Intentionally observing and documenting changes in our gardens leads to a heightened awareness that is a powerful tool in cultivating sustainable gardens and contributing to wider community sustainability’ [22].

We can ask the kinds of questions that will help us better understand the system as a whole. On this basis we can better prepare for the future. Questions might include:
  • What happens to the soil as plants reach maturity, and eventually die?
  • What happens to the plants and animals as soil health and water quality change? [23]
  • What is going to be most useful to do as a priority so as to help the garden rebound after an intense heatwave or a severe rainfall event?
Think about it

When seen as a whole, gardeners contribute to putting in place conditions more suited to the conservation of biodiversity. They also contribute to garden-centred social networks, based on the exchange of seeds and seedlings, food, knowledge, and other resources.

Greater biodiversity, combined with networking at the person-to-person level, helps to buffer the household and community from social, ecological, and economic disturbances. In this respect, resilience can be described as an emergent effect of other outcomes achieved in the home garden: resilience emerges when gardens are healthy, and when gardeners are connected and feel in control.

Source: based on Taylor and Lovell (2014) [24]

Reflections

What does ‘resilience’ mean to you as a grower?

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A resilient Australian (photo: Ron Woods)
References

[1] Marshall, T., 2012, Design for climate change, Organic Gardener, ABC, Sydney, https://www.organicgardener.com.au/articles/design-climate-change
[2] Cornell University, 2018, Gardening in a Warming World: A climate smart gardening course book, https://cpb-us-e1.wpmucdn.com/blogs.cornell.edu/dist/1/7755/files/2018/11/Course-Book-Fall-2018-289zx3u.pdf
[3] Climate Council, 2019, The facts about bushfires and climate change,  https://www.climatecouncil.org.au/not-normal-climate-change-bushfire-web/
[4] ibid
[5] NSW Department of Planning, Industry and Environment, n.d., Weather and climate in New South Wales, https://climatechange.environment.nsw.gov.au/About-climate-change-in-NSW/Understand-climate-change
[6] FFDI values below 12 indicate low to moderate fire weather, 12-25 high, 25-49 very high, 50-74 severe, 75-99 extreme and above 100 catastrophic. Average FFDI values are often used to track the status of fire risk – the highest average FFDI occurs in spring, and the lowest in autumn. (NSW Government 2014, op cit, p. 14)
[7] NSW Government Office of Environment and Heritage, 2014, North Coast Climate change snapshot, file:///C:/Users/117289/Downloads/NorthCoastsnapshot%20(1).pdf
[8] Climate Kelpie: Rounding up climate tools for Australian farmers, n.d., Climate drivers in New South Wales, http://www.climatekelpie.com.au/index.php/climatensw/
[9] MidCoast Council, 2020, Climate Change and the MidCoast, https://www.midcoast.nsw.gov.au/Environment/Climate-Change-and-the-MidCoast
[10] MidCoast Council, 2019, MidCoast Council declares climate emergency, https://www.midcoast.nsw.gov.au/News-Media/MidCoast-Council-declares-climate-emergency
[11] Greenbelt Foundation and the Royal Botanical Gardens, 2018, Gardening in a changing climate. Greenbelt Foundation, Ontario.
[12] Cornell University, 2018, Gardening in a Warming world: A climate smart gardening course book, https://cpb-us-e1.wpmucdn.com/blogs.cornell.edu/dist/1/7755/files/2018/11/Course-Book-Fall-2018-289zx3u.pdf
[13] ibid
[14] Urban Agriculture Forum, 2020, Climate Smart Food: Gardening in a Changing Climate – Part 1, https://uaf.org.au/blog/climate-smart-food-gardening-in-a-changing-climate-part-1/
[15] ibid
[16] ibid
[17] Climate Council, 2019, The facts about bushfires and climate change, https://www.climatecouncil.org.au/not-normal-climate-change-bushfire-web/
[18] ibid
[19] Urban Agriculture Forum, 2020, Climate Smart Food: Gardening in a Changing Climate – Part 1, https://uaf.org.au/blog/climate-smart-food-gardening-in-a-changing-climate-part-1/
[20] Jaworski, C., 2019, How will climate change impact pollination? AXA Research, https://www.axa-research.org/en/project/coline-jaworski
[21] Olsson et al., 2016, Peri-urban food production and its relation to urban resilience, Sustainability, 8(12), 1340, https://doi.org/10.3390/su8121340.
[22] ibid
[23] Cornell University, 2018, Gardening in a Warming World: A climate smart gardening course book, https://cpb-us-e1.wpmucdn.com/blogs.cornell.edu/dist/1/7755/files/2018/11/Course-Book-Fall-2018-289zx3u.pdf
[24] Taylor, J.R. and Lovell, S.T., 2014, Urban home food gardens in the Global North: Research traditions and future directions. Agriculture and Human Values, 31: 285-305.


Part 2 – Minimising water loss
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Maintaining the focus on the soil introduced in the first part of the MidCoast Grower's Guide, Part 2 discusses how well-structured soils contribute to maintaining soil moisture and minimising water loss. We consider water challenges in the MidCoast area, and additional ideas and tools to help you to maintain a dual focus on good soils and sound water management as you look forward to gardening for the long term.

Gardening for the long term includes preparing for periodic water shortages. 
​Steps you can take include strategic soil preparation and planting; mulching; and careful watering that minimises the use of potable water, while making the best possible use of rainwater. A key principle: Keep the soil covered!

Water challenges in the MidCoast area
​
​There is a close connection between temperature and the hydrological (water) cycle. This cycle describes the continuous movement of water on, above, and below the surface of the Earth, as well as the movements among water’s liquid, vapour, and ice states. The water cycle is affected by temperature: ‘Warming temperatures associated with a changing climate increase the rate of evaporation of water into the atmosphere, which will dry out some areas, and fall as excess precipitation on other areas.’
[1]
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Following protocols, water restrictions are put in place by Council as a response to shortages (source: MidCoast Council)
​Water management issues for communities on the MidCoast to consider include:
  • Water security in light of population growth and increased demand
  • Sustainable effluent management
  • Climate variability
For the region as a whole, ‘climate variability is likely to mean longer drought periods and more intense storm events’.[2]

A feature of the region is the experience of ‘wet droughts’, where raw water is unsuitable for harvesting due to its poor quality. There is the risk too of the loss of coastal assets due to sea level rise and storm surges.
[3]

For further information, take a look at MidCoast Council's information on Managing water use: Water restrictions [4]
Making the best use of available water
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Raised wicking beds (photo: Pat Burrows)
Soil preparation
The steps you take to prepare and nurture your garden soil contribute immensely to its moisture-retaining qualities. Methods include practising no-dig gardening and sheet-mulching wherever possible, and minimising soil compaction by using raised beds and designated pathways. The underlying principle is: the least disturbance to the soil, the better[5].

Soil conditions can be improved by breaking up any layer of hard subsoil or clay, and using infrequent but deep watering. These methods will enable plants to send their roots deep down, which also has the function of building up the soil profile, and adding organic matter at depth. All of this contributes to the soil’s water storage capability, and improving the ability of roots to find water[6].

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Farmlands in the valley of the Barrington River (photo: Ron Woods)
Did you know?
Apart from leading to high levels of carbon storage in the soil, improved organic matter content and continuous soil cover with plants or mulch keeps the soil structure in good condition.

​This helps the soil to cope better with more intense rainfall, which is predicted for many parts of Australia as the climate changes, because it can absorb moisture faster, thereby reducing run-off and erosion.[7]
Water wise planting
​
​
There are several planting options that are modelled on the way plant communities develop in natural ecosystems. When adopted by gardeners, these models are designed to use plants, soils, mulch and microbes to slow and treat storm water runoff [8]:
​​Rain gardens of any size or shape are strategically located in areas of the garden that are slightly lower in elevation. Stormwater is channelled into these dips, which can be planted quite densely, including with plants that tolerate being waterlogged for periods of time.

Bio-swales are shallow vegetated channels that can be used to direct surface runoff to rain gardens or other areas where the water can be absorbed and put to best use.

​Xeriscaping focuses on water conservation by designing a part of the garden to house plants that are drought resistant. This leads to the creation of a micro-landscape that requires much less watering[9].
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Rockpool with channeled rainwater (photo: Ron Woods)
​Practising crop rotation is key to avoiding disease build up and nutrient depletion in the soil. The health of your soil is also improved by using nitrogen-fixing plants such as legumes. Through their symbiotic relationship with nitrogen-fixing bacteria in their roots, ‘legumes convert atmospheric nitrogen gas into ammonium’[10].

​The use of groundcovers can also assist in conserving soil moisture and preventing erosion[11]. One way to do this is to incorporate as many perennial edibles into the garden as possible. Not only do they provide food, they also help to hold soil together with their roots, preventing erosion. They are generally more deeply rooted than annuals, and thereby more drought tolerant. Since they do not need to be replanted each year, there is less disturbance to the soil, helping the soil food web we discussed in Part 1 to thrive.
​In addition to water-wise planting, applying mulch, worm castings and compost to your garden soil will mean that you:
Spend less time weeding and watering
Use less synthetic fertilisers, or none at all
Promote healthier soils, and thus plants
Save time and money
Keep green waste out of landfill  [12]​
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Well mulced, and well watered, and the corn seedlings love it! (photo: Brett Cooper)
Watering
An essential aspect of managing and conserving water is to build a deep understanding of what happens to water in your garden. On this basis, you can adopt strategies that make the best possible use of rainwater, while minimising the use of potable water:
  • Install a rainwater tank wherever it is feasible to do so.
  • Hand watering and drip or micro-irrigation will conserve water by allowing you to direct the application where it is needed[13].
  • Applying water slowly will encourage infiltration and reduce runoff. Less frequent, deep watering also encourages deeper root growth to areas where the soil stays moist longer.
  • Integrate terraces, rain gardens and bio-swales into the garden. These are useful for slowly conveying and dispersing rainwater throughout, while preventing erosion of the topsoil.
  • Passive rainwater harvesting diverts water overland to vegetated areas for immediate use, and is another means of minimising surface runoff.
Local voice
Marnie Johnson, Misty Ridge
​
​The key to good soils is to aim for a minimum 30cm of rich, living topsoil that is well balanced in terms of its composition. To achieve this, take the time to carefully analyse your soil to work out what is going on, and then find the means to remedy deficiencies. It also requires acknowledging squarely what we’re dealing with in Australia.

Our ancient soil is becoming more hydrophobic (water repellent) and downgraded, and is struggling to hold on to the water needed for plants. With climate change, we’re seeing the atmosphere drying out especially during periods of extreme heat and dry, and sucking moisture not only from the soil, but also from the plants.
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Understanding your soil (artwork and text by Marnie Johnson)
Minimising water loss is key to good gardening, and it all begins with the soil. Here are some of the things we have done at in our garden at Misty Ridge near Gloucester Tops to get to the point of using up to 60% less of recommended water.
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Using soil inputs such as biochar, seaweed, compost and manures increases the retention of water and nutrients and makes for a happy crop of leeks (photo: Marnie Johnson)
​Start off by doing a soil profile. Dig in to shovel distance and see what you have in terms of subsoil, topsoil and humus. Check the soil layers for the depth of organic matter, sand, clay, minerals, and rock.

​
Test and adjust the pH:
  • pH values < 7.0 indicate acidic soils
  • pH values > 7.0 indicate alkaline soils 
  • 7.0 is considered neutral

Many of the things we grow like soils with a pH of 5.5 to 7.  

Add nutrients and aim to get life (bacteria, fungi, earthworms and others) into the soil through adding soil probiotics and lots of organic matter (discussed in Part 1 of the MidCoast Growers Guide) . 

At Misty Ridge we use inputs such as biochar, worm castings, wood vinegar, seaweed, compost, manures and others to increase water and nutrient retention. 
Keep the topsoil and its humus content protected through extensive mulching and the minimising of bare soil. There are differences of opinion on how deep the mulch should be, but at Misty Ridge we have preferred very deep mulch. This is good for reducing evaporation, protecting soil, and feeding microbes. Opinions also differ on using woodchips as mulch. Remember, as any mulch decomposes it uses up most, if not all, nitrogen from the soil. Also pine and eucalypt mulches feed the fungi that can make the soil plates hard and hydrophobic, so be sure to monitor regularly. Some useful mulches include rocks, straw and under-sowings (e.g. green manure).
 
If you’ve done all of the above, you should have improved water retention and reduced water use by at least 40%.

​Marnie is happy to share her wisdom and experience with others

​Visit her facebook page at 

www.facebook.com/marniesgarden/
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Marnie's Garden (photo: Marnie Johnson)
References
​[1] Cornell University, 2018, Gardening in a Warming World: A climate smart gardening course book, https://cpb-us-e1.wpmucdn.com/blogs.cornell.edu/dist/1/7755/files/2018/11/Course-Book-Fall-2018-289zx3u.pdf
​
[2] MidCoast Water, 2015, Our Water, Our Future 2045: MidCoast Water’s Integrated Water Cycle Management Strategy, MidCoast Council, p. 21.
​[3] ibid

[4] MidCoast Council, 2020, Managing water use: Water restrictions, https://www.midcoast.nsw.gov.au/Water-Services/Managing-Water-Use/Water-Restrictions
​[5] Marinelli, J., 2019, The Hidden Carbon Trap in Your Garden? It's All About the Soil, Audubon, https://www.audubon.org/news/the-hidden-carbon-trap-your-garden-its-all-about-soil
[6] Heft, T., 2013, A garden plan to survive heat waves, Big Blog of Gardening, https://www.bigblogofgardening.com/heat-waves-garden-design/
[7] Marshall, T., 2012, Design for climate change, Organic Gardener, ABC, Sydney, https://www.organicgardener.com.au/articles/design-climate-change
[8] Cornell University, 2018, Gardening in a Warming World: A climate smart gardening course book, https://cpb-us-e1.wpmucdn.com/blogs.cornell.edu/dist/1/7755/files/2018/11/Course-Book-Fall-2018-289zx3u.pdf
[9] ibid
[10] ibid
[11] Urban Agriculture Forum, 2020, Climate Smart Food: Gardening in a Changing Climate – Part 2,   https://uaf.org.au/blog/climate-smart-food-gardening-in-a-changing-climate-part-2
​
[12] Brisbane City Council, 2020, Compost and organic waste recycling, https://www.brisbane.qld.gov.au/clean-and-green/green-home-and-community/sustainable-gardening/compost-and-organic-waste-recycling
​
[13] Cornell University, 2018, Gardening in a Warming World: A climate smart gardening course book, https://cpb-us-e1.wpmucdn.com/blogs.cornell.edu/dist/1/7755/files/2018/11/Course-Book-Fall-2018-289zx3u.pdf
​Summarising the material in Parts 1 and 2:
By focusing on your soil, you will have provided the best possible conditions for your plants to flourish. Your garden as a whole will have greater resilience to challenges such as highly variable rainfall, and extremes of heat and drought. Good soil preparation can also contribute to making best use of the water that you do have by keeping as much of that moisture right there where you want it - in the soil.

Healthy soils help water to penetrate more deeply in order to reach plant roots. They help to reduce erosion when rainfall is heavy by absorbing moisture faster. 
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New growth through the mulch (photo: Daintry Gerrand)
​Reflections
How would you describe the system of mulching that you have adopted in your garden?

​Which are the materials and processes that have worked best, those have not worked so well, and those that are still in an ‘experimental’ phase?

​Part 1 – From the soil up
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Scraps to Soil
There are basically four options for dealing with the plant waste you have from the lawn, garden, landscape, and kitchen. The organic matter can: 
  • be composted in another on-site location
  • stay in place for decomposition
  • travel off-site to be put in a landfill
  • travel off-site for composting  
(Cornell University 2018 Gardening in a Warming World: A climate smart gardening course book)
​Of these four options, travelling off-site to be put in landfill is the least desirable. Food waste in landfill accounts for a significant amount of methane emissions.

The Scraps to Soil program
 focused on reducing organic waste going to landfill by providing an off-site means for composting in selected locations throughout the mid North Coast. The program is a NSW Department of Planning, Industry and Environment 'Waste Less, Recycle More' initiative that is funded from the waste levy. MidCoast Council took part in this initiative, working together with other councils as part of the MidWaste Regional Waste Forum. Scraps to Soil included a schedule of workshops run throughout the year across the LGA, online composting and worm farming tutorials produced by Tumbleweed, and a downloadable resource focusing on composting and worm farming.

Participation in 'Scraps to Soil' – Nikki Dixon, Bungwahl Public School
Bungwahl Public School took part in the Scraps to Soil program. One of the outcomes of this participation has been a reduction in lunchbox waste. Furthermore, the learnings from the program are integrated into a broader teaching/learning program at the school, in which children gain hands-on experience with gardening and composting, as well as enjoying the fruits of their labours.
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Photos: Nikki Dixon

​​Pupils helped to set up compost stations in the school’s permaculture garden (above). The compost is used to enrich the soil, such as in this delightfully repurposed boat where flowers for the share table are grown. It also provides herbs for the kitchen. 
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Did you know?
Soil carbon is the result of interactions among living plants, fungi, bacteria, and other soil organisms. Through photosynthesis, plants use energy in sunlight to convert carbon dioxide and water to the sugar glucose that they need to survive and grow.
Some of this liquid form of carbon, along with amino acids and other compounds, is also secreted by their roots, feeding soil organisms and promoting the production of humus.

Source: J. Marinelli (2019)
​Composting and worm farming are both excellent means of making use of plant waste, including kitchen scraps; and of contributing to the health of your soils. We'll look briefly at each in turn.
 
Composting
A regular routine of composting and mulching is one of the main ways in which gardeners actively perpetuate the carbon cycle[1]. Through onsite composting, we provide ourselves with a highly cost-effective plant food that is also beneficial to soil health. As well as creating organic fertiliser, composting reduces greenhouse gases, saves water, and dramatically reduces the amount of waste going to landfill, since around half of all household waste can be turned into compost[2].

Compost bins or heaps should be located on soil, not concrete, so that they drain well and that worms and bacteria can enter the bin to decompose the waste. All compost bins or heaps need a balance of organic materials that:
  • are high in nitrogen, such as chicken manure, and blood and bone
  • contain carbon, such as dried leaves and shredded paper
  • contain both carbon and nitrogen, such as green garden prunings and kitchen scraps.

Other considerations when setting up the compost heap or bin include that it needs to be easily accessible; to have enough water for the contents to be moist, but not wet; to have oxygen, which is done through the periodic turning over of the contents; and to have warmth, but preferably not direct sunlight all day[3].

When added to your soil, compost contributes to the soil’s humus content, that is, the dark, organic material that forms in soil when organic matter decays. Earthworms often help mix humus with minerals in the soil. When humus is in the soil, more nutrients such as nitrogen are available for plants. In addition, humus helps air and water move more easily through the soil so that oxygen can reach the roots of plants[4].
 
Worm farming
Worm farming is an approach to speeding up the natural occurrence and benefit of earthworms in your soil. You can buy worm farms from large hardware or gardening stores, or make your own. Worms eat almost all the nitrogen-rich materials that you would add to a compost heap. ‘One worm farm can consume the kitchen waste created by a two or three person household’[5].
 
Ingredients to avoid in your worm farm: 
  • Citrus products such as orange and mandarin peels
  • Onions
  • Chilli and garlic
  • Dog and cat manure
 
If you are going away on holidays, the worm farm will be fine to leave for up to two months. For this purpose, you would fill an entire tray with harder vegetables such as celery, pumpkin, carrots, and broccoli stems[6]. Worms will eat approximately half their body weight in food per day.

​The liquid that accumulates in the bottom tray of your worm farm is the ‘worm juice’ or ‘worm tea’ that you can use to replace the other fertilisers you might normally use. Dilute the liquid until it is the colour of weak tea (approximately 1:10 ratio), and use this to feed your plants every two to four weeks. The main product of the worms are their castings. They will be full of rich nutrients for your garden, and are ready to use when they are a rich, dark colour that resembles soil[7].

[1] Urban Agriculture Forum, 2020, Climate Smart Food: Gardening in a Changing Climate – Part 2,   https://uaf.org.au/blog/climate-smart-food-gardening-in-a-changing-climate-part-2
[2] Frankston City Council, 2015, Sustainable Gardening, https://www.sgaonline.org.au/pdfs/sg_frankston.pdf
[3] ibid
[4] National Geographic, 2020, Humus, https://www.nationalgeographic.org/encyclopedia/humus/
[5] Brisbane City Council, 2019, Worm farming, https://www.brisbane.qld.gov.au/clean-and-green/green-home-and-community/sustainable-gardening/compost-and-organic-waste-recycling/worm-farms
[6] ibid
[7] ibid
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Twilight at the Tops (Photo: Ron Woods)
Local voice 
Lee Fieldhouse, Island Biologicals ​

There is a definite link from good soils to gardens that are more resilient. Good soils enable water to penetrate and stay, and they contain microbes. If your soil is functioning microbially, you’ll be better able to withstand climate extremes because a high level of organic matter is constantly being cycled through the soil. The carbon in turn increases the soil’s ability to hold water.

Soil microbes include bacteria, protozoa, and fungi. They are extremely tiny, you are not able to cast your eyes upon them. One teaspoon of good soil contains an incredible number of microbes - they make up a large proportion of life on Earth.  These microbes are cycling the nutrients of the world by turning organic matter such as crop residues, grass and pieces of wood into humus-rich soil that plants can draw from again.

Plants also provide food to microbes through carbon-rich secretions from their roots – that’s how carbon is sequestered into soil. What plants do is an important part of the carbon cycle. The microbes in turn access minerals from further away and feed them to the plant’s roots. When artificial fertilizers are used, you’ve cut off the relationship between the plant and the microbes and carbon sequestering doesn’t work so well. The plant no longer needs to work to find its nutrition and no longer returns its carbonates to the soil.

To build good soil, remember that soil, microbes and plants are in a constant symbiosis, they can’t live without one another. Keep the carbon cycle going. Don’t put plant material and kitchen scraps into landfill. Having bare soil is detrimental, so have living plants or organic matter that is breaking down (mulch) on the surface of the soil at all times. This also helps to slow runoff and to keep more water in the soil.

​Find ways to provide some shade. If you’ve got 40 degrees, the plants and the life in the soil will like a bit of shade. Through composting, you’re putting the building blocks of soil functioning into place. Compost adds organic matter as well as microbes to your soil. You’re aiding plants to grow better and to photosynthesise better, but it’s not fertilizer. It is also an excellent way to turn organic waste into a highly valuable gardening resource.

Worm farming is another way to feed your soil. To better understand why it’s useful to farm worms, think of the earthworm as having three parts: the front end is a detritus shredding machine; the middle part is a fermentation chamber that breaks down the matter with the help of micro-organisms and heating; and the back end is a bio stimulants distribution area. Worms will tunnel around, bringing air and water into the soil, taking organic material deeper down, and bringing minerals up.

​Through turning the soil in this way, all non-mechanically, they create an environment for more microbes to exist. To encourage worms in garden beds, add organic matter, keep mulch on, and try to garden with minimal mechanical disturbance. Keeping the soil covered is what the earthworms would prefer.

Tips for worm farming: keep it in the shade, that’s number one. Don’t overfeed, worms can only consume so much. Leave the tap open, and capture the liquid in a bucket if you wish to use it.  A well-functioning worm farm shouldn’t smell bad. If so, it means something isn’t going right, usually that it’s too wet. If so, put in more dried leaves and other things that will soak up that moisture. The castings are ready to use when they are pretty much all in the bottom tray, and most of worms in the second level. You shouldn’t recognise anything in it any more – then it’s ready.
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​Lee shares topical information on soils, composting and worm farming at the Island Biologicals website, see  https://www.biocast.com.au/​​
​Reflections

​Think of additional ways in which you could best make use of the organic waste that your garden and household generates and avoid any of it going to landfill.

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For this project, the Midcoast Growers Network was sponsored by MidCoast Council as part of the Scraps to Soil program . The program is a NSW Department of Planning, Industry and Environment 'Waste Less, Recycle More' initiative that is funded from the waste levy. 
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