CULTIVATING TRUFFLES IN SA

Background information for the grower … THE BASICS


Is your Area Cold Enough ?

The most important step is to establish if you have the right cold units. We need 800 cold units for truffles to be successfully propagated in your area.

Your day and night average winter temperature needs to be about 8° degrees . Lower temps are OK but higher temps are not ideal and would have to be tempered by mulching.


Site Establishment

Your site selection is the second most important step toward successful truffle production. 

Take sun and wind direction and water availability into consideration when choosing a site.

The French black truffle (Tuber melanosporum) needs a climate without extreme summer heat or extreme winter cold. Mulching and irrigation methods can modify conditions and make marginal areas suitable for truffle growing.

Truffles require well-drained soils. The French Black Truffle tolerates a broad range of soils from sandy to clay loams, including rocky soils.

Woodford truffles team of experts will work together with you to confirm the most suitable site.


Soil preparation

You should have the soil tested to measure its natural pH, buffering capacity, organic matter content and the availability of plant nutrients. The suitable soil pH range is between 7.5 and 8.3, but 7.9 (water reading or 7.2KCl) is considered ideal.

The best method is to raise the pH to 7.9, well before the trees are planted to give potential fungus competitors as little opportunity as possible.  It takes a long time, to raise the pH usually, but few farmers are usually willing to wait that long before planting.

The amount of lime required to raise the pH varies with the starting pH, the soil texture and buffering capacity and the type of lime that you use. The ideal pH is way above levels ideal for maximizing soil fertility and approaches the level where most plants begin to suffer from various nutrient deficiencies. Consequently, agricultural specialists will have a difficult time predicting the amount of lime required to raise the pH since they typically have no experience with raising pH to these levels. The task for the truffle farmer is to add lime incrementally with continued pH testing until the ideal pH is reached. Lime can take as much as a year to change the pH and it is often difficult to add enough lime in a single application so the process of applying lime is necessarily gradual. Once the ideal pH is reached it will need to be maintained with supplemental lime applications as necessary.

Ploughing before planting out is advisable to remove all vegetation and with it possible mycorrhizal contamination. A cover crop of orchard grasses are resown subsequently.

 

Irrigation

As the melanosporum truffle originates from the northern hemisphere and grows with the natural rainfall there, we need to emulate these conditions if we want to be successfully cultivating it in the Southern Hemisphere. Our ultimate spacing of trees will be 8m X 8m and we want to blanket-irrigate under the tree-canopy to keep the soil-moisture available all over.

A good supply of quality water is essential. Our specialists recommend 4 000 to 6 000 cubes per annum which includes the rainfall. Truffles require a good downpour in spring and autumn for the truffles to form and to grow to maturity. If your area's climate does not provide this, supplemental irrigation will do the trick.

 

Planting out

We like to plant about 400 trees per hectare. More trees will work as you will get mycelium coverage reaching from tree to tree earlier. We are emulating a European woodland at the edge of the forest where sunlight filters down to the ground.

Woodford will supply a mix of English Oak, Evergreen Oak as well as Spanish Rock-Rose to create the orchard suitable for your region.

 

Management

If the soil was properly prepared at the liming stage, little will have to be done for some years depending on local conditions. Additional liming is usually required at a later stage, and can be applied through spreading ‘Aquastep' chips, or in the water supply by raising the pH of the irrigation water.

Our forester will visit on a regular basis to advise on tree-pruning and disease control. Leaf sampling will show trace element shortages and corrective steps will be advised.

As we do not want to compact the soil in the orchard in any way, only a very light tractor should be used to mow and annually aerate the soil with a shallow-tined tool.

A brulé (burnt area) will form under the trees indicating that the mycorrhiza is growing and working.    At least once a year, one of our team of experts will visit the orchard to identify the mycorrhizal progress.


Harvesting

"Woodford" has employed the services of a team of animal trainers to train dogs to sniff out the truffles. The team will visit the orchard at the start of harvest time in winter to help identify the onset of production.