ESTABLISHING A TRUFFIÈRE
In Europe, truffles thrive in nutrient poor, calcareous (lime) soils and a temperate climate. Therefore to establish a truffière in Australia we choose areas with similar climates including rainfall & winter frosts, sufficient available water for drought proofing, and apply a great deal of lime to replicate the European soil types.
- Cold winter temperatures with a few frosts
- Hot summer temperatures for initiating truffle formation
- Free draining soils, suitable for altering with lime
- Sufficient Irrigation water (drought proofing)
SOIL AND NUTRIENTS
Our Australian soil are typically acidic, and need to be ameliorated with lime and/or dolomite to adjust the pH to the desired level (pH 8). A soil test is required to determine how much lime is required to raise the pH (see Truffle Soil Test page) along with other key characteristics.
A soil test is important to determine other nutrient levels, physical properties (drainage, etc.) and the results considered for suitability regarding truffle production. Desirable soils for traditional farming may not actually be suitable, conversely poor soil types do not automatically preclude possible truffle production.
For example, Agricultural soils that have been heavily fertilised (NPK) or had chicken manure used often or recently, may be too rich in available phosphate and may not be suitable for growing truffles.
Soil preparation -ripping
See notes on the Truffle Soil Test page
Nutrition of trees
Truffle trees generally do best in soils that are low in available mineral nutrition, especially phosphorous. This promotes the symbiosis with the truffle mycorrhiza. The truffle absorbs phosphorous and other nutrients from the soil and provides them to the tree roots. In turn the tree provides the truffle with photosynthesised carbohydrates and sugars for its growth.
The general advice is not to use mineral NPK fertilisers but to encourage the organic system. A healthy organic soil is rich in Actinomycetes (a false fungi responsible for decomposing organic material) and many types of soil bacteria especially photosynthetic bacteria and nitrogen fixers. These become the food sources for the next level of protozoans which keep spring tails and other macro fauna happy. You can usually identify when your soil is bio-active by the strong presence of tiny animal life, including earthworms, and a rich “earthy mushroom” smell (this is the actinobacteria at work). The result is freely available organic nitrogen and a range of naturally chelated plant nutrients. In short a healthy, well balanced soil.
Generally the required level of organic activity in Australian soils is low so plan to stimulate soil microbes with organic supplements (see information on kelp, fish emulsion, worm leachate, biochar and molasses). The Truffle Ready Soil Test is able to make recommendations for the addition of organic supplements.
The applied calcium (lime) can be leached over time however building a strong organically rich soil will tie up the calcium and reduce the losses.
The following is a schedule of soil preparation activities;
- The initial preparation activities involve ripping the soil to a depth of 20cm followed by cultivation of the top soil to a fine tilth.
- Following the soil test, the advised quantity of agricultural lime and/or dolomite is applied by a belt spreader. Bio-char (if recommended) should also be applied at this time. This is needs to be incorporated usually by rotary hoeing.
- Allow about 3 to 6 months for the alkaline reaction within the soil to occur.
- Approximately two weeks prior to planting, the required organic stimulants and trace elements are applied.
- Prior to planting the irrigation laterals, solenoids and lines are installed and buried.
- Truffle colonised trees are planted
- Tree guards are immediately fitted to protect the plants from the weather and animals.
- Adequate fencing, preferably electrified should be installed around the entire truffière to prevent tree damage from rabbits, wombats, etc. Foxes have also been known to dig up ripening truffles also.