Undervine cultivation – A learning experience

By Caine Thompson, Viticulturist, Mission Estate

After a slow start to the growing we are now in full swing with rapid shoot growth occurring across the vineyard! With these types of weather patterns weed growth has been constant which has kept us on our toes in regards to weed control in the organic parts of the vineyard.

The conventional areas have received two weed sprays so far this season and we have now cultivated twice across the organic parts of our Mere Road vineyard. We are using the Moteo Ridge single sided front mounted cultivator (see photo below). The unit is mounted to our forklift on a tractor and uses a small disc to cut into the soil. This is followed by a blade that moves between the vines, retracting from the trunks when the sensor arm comes in contact with either vines, posts, stays or irrigation risers.

I’m pleased with how the unit is working after a few wrinkles were ironed out. We have three staff members trained in the operation of the unit and we are finding that the performance is improving as staff become more experienced in the operation.

The key really is in the set up of the machine. Our project advisor Bart Arnst spent some time with us fine tuning the set up to optimize the performance, which instantly saw an improvement in control.

Some of my key observations are:

–       After the initial “mounding up” stage of cultivation, you don’t need to cultivate too deep. If you do (like we did), the weed roots seem to sit in the same place and then with irrigation or rain easily and quickly reroot and establish, which is not ideal.

–       Instead a shallower cut takes these weeds out and pulls them from their location and moves them slightly down the row, which disrupts the weed roots

–       The sensor arm needs to be offset to the blade to give the blade enough time to retract around the vines (especially important when trunks are not straight).

–       Speed. If you go too fast the machine leaves a ‘shadow’ effect around the base of each vine and post. We have found that 3.5km/hour is the most optimal speed for our situation.

Young vine staked for cultivation

–       The speed at which the blade retracts can also be adjusted to help avoid ‘shadowing’ as well.

–       The front disc isn’t always needed. We found by removing this we aren’t getting a build up of grass in this disc which was affecting the sensitivity of the sensor arm. This was causing a ‘bulldozing effect’ which wasn’t ideal. By removing the disc we are now doing a much better job (see photo at bottom)!

–       Young vines planted within established blocks need to be protected. There needs to be something strong and rigid to activate the sensor arm so that the blade can retract and move around the vine. We are using two bamboo stakes around each vine, which protects it from both passes of cultivation. It is working extremely well, no damaged young vines when this has been done!

When Bart comes up again we will get his thoughts again on our operation and the machine itself and how it can be further refined. But hopefully we have it sorted now!

Certainly our progress in performing cultivation has drastically improved since his first visit!

A good result