Vineyard Soil Update – August 2010

Keeping in Balance

Rich Williams, Vineyard Manager and Robin Dicey, our Viticultural ‘Godfather’, have just undertaken some very detailed analysis of our soils across our eight different vineyard blocks and the very informative soil test results are now back. Ideally soil should comprise 25% water, 25% air, 45% minerals and 5% organic matter with the ideal soil pH should be between 6 – 6.5. In terms of our minerals, we have known all along that our soils are very low in Magnesium and nutrients have been applied for a few years now to try and bring it back into line.

It hasn’t seemed to have much of an impact on the soil and through tissue analysis it has been shown that the vines are still deficient in it. This can have repercussions on growth as it is a major factor in photosynthesis.

We are now using the Albrecht system and the way it works is to put the main soil nutrients back in balance with one another so that these forms of nutrients are not locked up. These main soil nutrients are Calcium, Magnesium, Potassium and Sodium. The Base Saturation of these nutrients changes depending on how much organic matter we have in the soil (which in our case is very low) and soil pH. Because our soils are less able to hold as much as they could, it is very important we at least have our base nutrients in balance so that the plants are able to take them up when they need them.

Also it seems our soils are very low in trace elements such as Boron, Zinc and Copper. The first two have some of the biggest influences on flowering and pollination than any other so it is important we have them in the soil.

What the test results have shown is that we are not far out of balance of our major nutrients on the whole. Some blocks are a little more out of balance than others. i.e. the Lake Front block is very well balanced in base elements however it is a bit out of balance in trace minerals; the Ski Slope is quite out of balance on the base elements and a little out on trace minerals; the Fruit Bowl/High Wire block is very good on base elements but not so with the trace minerals, etc. Getting these all back into line is key to continued quality in the wine.

We are about to undertake this long-term program to increase our soil fertility and bring all the blocks into perfect balance and maintain good stewardship of our land which is farmed according to the certified Sustainable New Zealand program.