Planting a new vineyard is a major investment. Finding available sites in suitable areas is not always easy. However when a potential site is found, it is essential that the suitability of that site is evaluated against the type of grapes and wines the purchaser intends growing there.
That means looking at (meso) climatic information, orientation, availability of water and of course the soil.

The soil forms a major part of what the French call Terroir, and will have a major influence on how the vines will perform and which vines or rootstocks are most suitable for the site and type of grape/wine intended.

It is imperative the soils are tested before purchasing/planting any vines. This soil test should not be limited to a simple Basic test of the topsoil. It should include comprehensive testing of both the top and subsoil.

The analyses should include organic matter content, sometimes reserve phosphorus, sulphur and nitrogen levels.
In many cases it is desirable to establish nitrogen levels (available as well as reserve (organic) nitrogen because of the effect nitrogen has on vigour.

Trace element tests are important to determine potential problems (high copper levels in old orchard soil, or low boron for instance). In some areas soluble salts or high chlorine levels could also be a problem.

Structure and texture of the soil should be examined, as well as the nature of the parent material. Structure and texture of the soil are extremely important parameters for vine growth, especially for the production for quality grapes. It determines the amount of moisture a soil can hold, whether there are likely to be problems with waterlogging (big problem for vines) or compaction layers restricting root development.

A number of pits should be dug to investigate these parameters. The presence of compacted layers can also be detected using penetrometers to measure soil strength (measuring the force needed to push a rod with special cone into the ground). Compaction can have major effects on vine performance, often growers are not aware of the presence of compaction layers or hardpans and/or the consequences of these problems.

A trial conducted in our own research vineyard (pictured) clearly indicated the serious effects of compaction on newly planted vines.





Where irrigation is going to be used the quality of the water needs to be checked. AgConsult can help you with this site evaluation anywhere in New Zealand.

We have provided training for a number of different companies.  Training included issues like:

• General soil and fertiliser issues
• How to interpret soil test data
• Effects of fertilisers in terms of nutrients and soil biological activity
• Liming options and effects on soil
• Calcium uptake in plants (horticulture)
• Plant requirements
• Soil biological activity including:
• Importance of mycorrhizal fungi
• Suppression of soil pathogens
  

Study Tour, Spanish Vineyard