Soil, Nutrition and Compost

Seaweed extract can be used to reduce the effect of stress on lettuce production in water limited environments. Based on this research with cos lettuce in sandy loam soil, a similar fresh weight was achieved despite a 40% reduction in irrigation when Seasol was applied. There is a significant body of international research confirming the benefits on water use efficiency or drought tolerance using seaweed extracts.
Reduced irrigation rates can save fertiliser nutrients by limiting nutrient leaching through the soil profile. Water use efficiency may become important in Australia in 2024 and beyond as El Niño becomes more likely.

This fact sheet from VegNET Tasmania steps growers through the key considerations to maximise the use of your fertiliser, including establishing healthy plant roots, improving soil structure and establishing strong fertiliser practices using the 4Rs (right source, right rate, right time, right place).

As compost is treated to kill human pathogens, it can be used freely on vegetable crops with no withholding periods. However, evidence of treatment must be provided.

Without this evidence, compost that contains manure (or other animal products) is considered “untreated”. It therefore attracts the same food safety restrictions as raw manure.

Compliant Compost is a new, simple code of practice that can be independently verified by approved auditors. The code is focused on demonstrating that the compost will not introduce human pathogens into the environment or onto food. Compost certified using the “compliant compost” program can therefore be used on farm without restriction.

Interest is growing around biochar as both a soil amendment and to increase carbon sequestration to soil.

This fact sheet explores what biochar is, how it can be used in vegetable production, what to consider if using biochar, and where you can get it.

Soil pH has a profound effect on nutrient availability to plants and microorganisms, and thus soil and plant health.

This fact sheet shares the results of a field trial in north-west Tasmania using several treatments to raise pH in an acidic soil and a cost benefit analysis.

The potential for cover crops to provide protection from erosion is multifaceted.

In this multisite trial in North West Tasmania, seasonal cover crops were used to protect bare fallow autumn and winter soils from erosion. Read more in this fact sheet.

A healthy soil is productive, sustainable and profitable. But what exactly does 'soil health' mean for vegetable growers?

This fact sheet shares some top tips for vegetable growers when it comes to defining soil health.

There are various ways to reduce erosion, including reducing how much water runs off and the speed of that flow.

This fact sheet provides information on a trial conducted at Forthside Vegetable Research Station at Forth in north western Tasmania, which compared three treatments with a control (no treatment) to reduce the amount of water moving down a hillslope.

Soil health is closely linked to soil microbiology. This fact sheet outlines information on a broad group of soil microbes including fungi, bacteria and pseudomonas, and explains how different levels, numbers and ratios of these microbes can impact the overall health of your soil and crops.

Recycled organics are compostable organic materials, including garden organics, food waste, residual wood and timber. Recycled organics compost is derived from shredding and stockpiling these green wastes for up to six months before being screened to remove contaminants and create a compost high in organic matter, essential nutrients and beneficial bacteria.

Compost made from recycled organics is an effective, long-term soil conditioner against drought. Recycled organics will improve the water use efficiency of a farm by capturing more water and holding it for longer.

Over time, an increase in organic matter will improve water holding capacity, soil structure, soil porosity and hydraulic conductivity. Recycled organics applied to the soil surface will also reduce soil crusting and improve water infiltration.



This project is supported by the NSW Environment Protection Authority as part of Waste Less, Recycle More, funded from the waste levy.

Recycled organics are compostable organic materials, including garden organics, food waste, residual wood and timber. Compost made from recycled organics is derived from shredding and stockpiling these green materials for up to six months before being screened to remove contaminants and create a compost high in organic matter, essential nutrients and beneficial bacteria.

Managing plant nutrition is integral to producing a healthy, profitable vegetable crop. The Soil Wealth ICP team has collated a range of informative resources to help growers, advisors and other vegetable industry service providers to better manage crop-specific nutrition.

Sodicity is different to salinity, but it can still have a negative impact on soil structure and crop growth.

This fact sheet explains what sodicity is and how it differs to salinity; how to identify sodicity in soils and its impact on soil and crops, as well as management options.

Soil sampling and testing is usually done prior to planting a crop; specific in-crop testing can be useful e.g. testing for available nitrate and ammonium.

A soil test report is only as good as the care taken in sampling. Tools and equipment should be cleaned prior to collecting each sample. Completing labels and writing on bags or containers before going out to the field can save some time and confusion.

Read this fact sheet for guidance on how to take soil samples correctly and obtain reliable information on the nutrient status of your soil.

Testing for soil nitrate is important to manage nitrogen availability in vegetable crops to ensure optimal yield and quality.

This simple and easy to use guide has been developed to show how a quick nitrate test can be conducted in the field.

Phosphorus (P) is a major element (macronutrient) that plays a number of important roles in plants, such as productivity, crop quality, increased root growth, and earlier crop maturity. It is necessary for proper cell division and formation of new cells. It's important that soil P is managed correctly for crop nutrition.

This fact sheet covers the common characteristics of soil P and its availability for uptake by plants such as pH, mobility and microbial activity, and provides practical management tips and tools in line with the ‘4Rs’ - right source at the right rate, right time, right place.

The rising cost of fertiliser inputs and a greater understanding of the importance of soil health has prompted interest in the use of composts as a soil ameliorant. What exactly are composts and why would you use them in a vegetable production system?

This fact sheet provides a summary ‘breakdown’ on the current knowledge of the benefits and risks of composts, with links to further information available.

Salinity issues can appear in all major vegetable production areas; they can come and go depending on weather and changes in water quality. It can occur naturally or as a result of management practices.

Read this fact sheet to find out more about good salinity management practices on farm, salinity thresholds for vegetables, how salinity can be identified and measured, as well as appropriate EC ranges for soils and water.

The factsheet summerises cover crop selection, biofumigants, termination and incorporation for the Wide Bay Burnett region in Queensland and produced inconjunction with VegNET.

Calcium cyanamide Fertiliser, also known as nitrolime, has been used in Germany as a slow release nitrogen and calcium fertiliser with liming effect for over 100 years.

This fact sheet documents the findings from a grower-led demonstration where calcium cyanamide (CaCN2) was applied as a wax coated fertiliser prior to a carrot crop in Western Australia in 2017.

The Soil Wealth and Integrated Crop Protection case study demo site in north west Tasmania is Harvest Moon. This fact sheet showcases one of the practices employed at Harvest Moon, the ripper mulcher, which is used to manage the risk of soil erosion.

Vegetable cropping can leave topsoil vulnerable to significant erosion, and the ripper mulchers are free for Tasmanian growers to borrow and use.

Soil acidification, the drop in soil pH, is due to several factors including leaching of nitrate nitrogen, nutrient uptake by crops and root exudates, build-up of soil organic matter and use of nitrogenous fertilisers containing ammonium and urea.

Choosing the right lime product and applying it at the correct rate is important in managing soil acidification and the subsequent impact on vegetable crops.

Read this useful fact sheet to find out more about the causes and effects of soil acidification, how liming increases soil pH differently depending on your soil type, different products, as well as managing paddock variability.

Strip-till is a system of cultivation that works strips of soil where the crop will be planted or sown and leaves most of the soil covered and undisturbed.

Read this fact sheet to find out more about the benefits and challenges of strip-till, as well practical considerations out in the paddock.

Using water efficiently means applying enough water to meet the needs of the crop - not more, not less.

A soil in good condition consists of around 50% solid matter; this includes organic matter. The remaining space should be half filled with air and half with water. Organic matter is the main driver of soil health.

Read this practical fact sheet for guidance on readily available water (RAW) and soil texture, as well as healthy soil conditions.

Labile carbon is the carbon most readily available as a carbon and energy source to microorganisms.

Read this fact sheet to find out more about labile carbon and its use as a 'leading indicator' of soil health, as well as undertaking your own labile carbon field test to see for yourself.

Calcium Cyanamide Fertiliser, also known as nitrolime, has been used in Germany as a slow release nitrogen and calcium fertiliser with liming e ect for over 100 years. It was introduced into Australia by the German manufacturer Alzchemie AG Germany (www.alzchem.com) in 1996.

Nitrogen (N) is an essential nutrient for plant growth, development and reproduction, so it’s important to ensure your crops have enough!

Read this fact sheet to find out more about the steps to providing the right amount of nitrogen, managing and monitoring N, and how nitrogen use efficiency (NUE) data can be interpreted.

This fact sheet outlines key factors and the management options for the successful transition from cover crop to cash crop in vegetable production systems.

Anhydrous ammonia has long been used as a preplant and side dressing fertiliser in the cotton and grain industries. It results in a high retention of nitrogen in the soil, reduced leaching of nitrates through the soil and yield increases in various crops. However, it needs to be treated with care as it can cause injury to farm workers.

Anhydrous ammonia has beneficial effects on soil microbes, nitrifying bacteria and worms. It is more suited to row crops rather than babyleaf crops, where even distribution nitrogen in the soil is required.

Over the past four years, the effect of pyrethrum marc on vegetable crops has been compared with biochar, oaten chaff and conventional fertilisers at a trial site in Tasmania.

Pyrethrum marc can offer benefits as a soil conditioner and also as a source of nutrients for crops. Amendments can provide benefits for one or more years after application. Therefore, soil testing and monitoring combined with a fertiliser program is important for making the most of the economic benefits. Based on the crops grown and yields achieved in this trial, if pyrethrum marc was $60-65/t delivered, it would provide at least similar returns to conventional fertiliser.

Read this fact sheet to learn more about the trial, crops grown, treatments, and results.

Soil health refers to the fitness of the soil to achieve its potential, within natural or managed limitations, and be productive under
the intended land use. Healthy soils have physical, chemical and biological properties that sustain biological functioning, maintain environmental quality and promote plant, animal and human health.

This practical fact sheet outlines the importance of healthy soil, its characteristics and how to get there, as well as the main soil health issues and potential solutions.

Nitrogen is a key input into vegetable production. Applying high levels of nitrogen, either as fertiliser, compost or amendments is necessary to achieve high yields, but it can also result in nitrous oxide gas being released into the atmosphere.

This fact sheet provides useful information on the loss of plant available nitrogen, reducing nitrous oxide emissions, nitrogen management (the 4 R's) and keeping informed through soil testing.

Compost is a mixture of recycled organic materials that have been processed by natural organisms, breaking down the original materials into a usable form. Compost has many benefits for soil. It can feed plants, stimulate beneficial microbes, improve soil structure and help the soil retain nutrients, water and warmth.

This guide describes how fresh produce growers can use compost without affecting their food safety assurance program.

Compost is a mixture of recycled organic materials that have been processed by natural organisms, breaking down the original materials into a usable form. Compost has many benefits for soil. It can feed plants, stimulate beneficial microbes, improve soil structure and help the soil retain nutrients, water and warmth.

This guide describes how producers of recycled organic products can ensure that the composts they supply meet the requirements of food safety programs such as Freshcare.

Match your main soil management aim to the southern Australian summer cover crops.

Plant nutrients are commonly split into two categories:

• Major elements (macronutrients) that are required in relatively large quantities by plants, and
• Trace elements (micronutrients) that are essential for plant growth, but are only required in small amounts.

All elements must be available in a form that is useable by the plant, and in balanced concentrations that allow optimum plant growth.

Download this great summary of what the plant nutrients do, and how they need to be applied for the plant to make best use of your investment in fertilisers.

Match your main soil management aim to the southern Australian winter cover crops.

Silicon is an available nutrient for all plants grown in soil, with its content in plant tissue ranging from 0.1%-10%. Although it is not currently classified as an essential nutrient for plant growth, recent research suggests that silicon may have a significant role to play in plant health.

Read this fact sheet to learn more about the benefits of silicon on crop health and subsequent production, including improved nutrient availability, plant resistance to pest and disease pressure, and improved resilience to environmental stress. Guidance on how to choose a silicon product is also provided.

Maintaining or increasing soil carbon makes good sense – for the environment and for soil productivity. While climate scientists talk about soil carbon, you will know it better as soil organic matter. And the productivity benefits of soil organic matter are legendary:

• Providing a slow release supply of nutrients
• Improving cation exchange capacity and nutrient- holding ability
• Buffering against soil acidity
• Improving soil structure and aggregate stability
• Improving soil water holding capacity
• Reducing erosion risk.

This fact sheet summaries the opportunities and management options for mitigating or sequestering soil carbon in vegetable soils.

A healthy topsoil is a great asset to have, as this layer of soil contains the highest concentration of organic matter, micro-organisms, nutrients and biological activity. Lost topsoil can’t be replaced in a human’s lifespan. Therefore erosion, probably the biggest culprit in the loss of topsoil, should be effectively managed.

This fact sheet provides essential information on managing soil erosion, including reducing the impact of wind and water. The easy to read publication also guides decision-making on managing your irrigation system, controlling run-off water, covering exposed soil areas, improving soil structure and increasing cohesion between soil particles.

This is the first fact sheet in a series for vegetable growers. These sheets provide information about composting, compost products and how to best use them to suit your needs.

This is the second fact sheet in a series for vegetable growers. These sheets provide information about composting, compost products and how to best use them to suit your needs.

This is the third fact sheet in a series for vegetable growers. These sheets provide information about composting, compost products and how to best use them to suit your needs.

This is the fourth fact sheet in a series for vegetable growers. These sheets provide information about composting, compost products and how to best use them to suit your needs.

This is the fifth fact sheet in a series for vegetable growers. These sheets provide information about composting, compost products and how to best use them to suit your needs.

This fact sheet developed by NSW Agriculture provides a good overview of composting, its benefits and how to create good compost.

Soil salinity can cause salt burn, affect crop quality and reduce yield. Incorrect soil nitrate levels affect crop growth, quality and yield and excessive nitrogen applications are wasteful and can result in contamination of water tables and waterways. It is essential that soil salinity and nitrate levels be monitored throughout the crop cycle to ensure optimum crop growth.

Soil solution extraction and analysis can inexpensively monitor both salt and nitrate throughout the growing season to ensure optimum crop growth.

To find out more please refer to this fact sheet developed by Steven Falivene from the NSW Department of Primary Industries.

Biofumigation is the use of specialised cover crops, which are grown, mulched and incorporated into the soil prior to cropping. High biomass, especially roots, can provide the traditional benefits of green manure crops, and if done right, naturally occurring compounds from the biofumigant plants can suppress soil-borne pests, diseases and weeds.

Reduced till is a system change that relies on keeping the soil in a healthy condition through the use of permanent beds, controlled traffic, cover cropping and crop rotations rather than frequent cultivation.

This fact sheet covers the Sources of nitrogen on farm, Fertiliser use - what to do and what to avoid and a Quick guide to the main nitrogen sources in fertilisers.

Cadmium is a widespread, naturally occurring, element that is present in soils, rocks, waters, plants and animals. It is crucial to limit our long-term exposure to cadmium, as it can accumulate in humans and high levels can affect human health.

This article originally published in Vegenotes, provides an insight into managing cadmium in vegetable production.