By Jacqueline MacLaurin, Viticulture Technician, Wither Hills
Spring has arrived.
September has been a busy month — the calm before the storm of growing season. Growth appears to have been slower to start this season, which in hindsight has allowed us to complete tasks in the vineyard. The last of the broken posts have been replaced; we have chosen to use Eco-steel posts. Due to the new prohibition on using treated timber posts as replacement posts under USDA and Canadian organic rules from 1 July 2010, many treated post alternatives have arisen. It is well worth researching the options available and pairing the alternatives to your site, plant canopy growth and likely harvest method.
I have chosen the Eco-steel posts because of the ease of putting them in the ground and attaching clips to the post. Major factors in my decision were the price and availability, making sure there was a ready stock we could purchase from. So far the only issue we’re having is the height of the holes in the posts matching with our desired lifting wire heights. I will be sure to cover in future blogs how they respond to a full canopy with our gusty norwest winds, and going through the machine harvester.
Other tasks in the vineyard during September included lifting the irrigation wire to a height of 500mm above ground to accommodate undervine cultivation in the organic blocks, and picking up large rocks that prove a hazard to machinery. When choosing to convert from standard management practices to organic management practices, one of the major choices that needs to be made is how to manage the weeds or unwanted plant species under the vine. Again there are several choices for undervine management, and it’s best to choose that which suits your site. The two most common options are undervine cultivation — disturbing or cutting the roots of the weeds to limit growth; and undervine mowing — cutting the weeds off at ground level.
On our site, located on stony alluvial soils, we have chosen to use a Braun undervine weeder. As we have become more familiar with this piece of equipment and the implements that can be used in conjunction with it, we have seen some great results in the block. In September we did our first post-winter mounding pass with the weeder. The biggest test around weeding is the strength of character in you, as the manager or owner, to allow your vineyard to look ‘rustic,’ and to change your belief of what a vineyard ‘should’ appear to look like from the outside.
On site we also had an old weedspray unit, previously used to apply soil drenches to another organically managed block, that we have mounted on the back of the tractor used for undervine weeding (UVW). Through this we are able to spray a mixture of seaweed, Effective Microorganisms (EM) and molasses onto the soil every time we do a pass with the UVW. This brew is a great food source of sugars for the microorganisms in the soil, hopefully increasing their populations.
As mentioned above, we have tasked the team with picking up large rocks in the organic blocks. Under previous management the rocks have largely been undisturbed, but with the cultivation of the inter-row and undervine we have unearthed rocks — many of them, and some dangerously big. Due to the rocks being undisturbed for a long time, with the first pass of the UVW they may flick out and go into the inter-row, where in our situation they have posed a problem for mowers and machinery alike. Hopefully as the soil becomes more friable the rocks will roll with the passing of the UVW and no longer be an issue. At the moment we will continue to pick up the large rocks out of the vineyard when time allows.
I will aim to follow these activities through the season and share our experiences with you. If anyone has any questions, feedback or ways in which they have managed similar issues in their own situation please get in touch and share.
Enjoy the new season of Spring.