Unwanted rootstock growth

There are lots of good reasons to use rootstock-grafted vines aside from their ability to grow in phylloxera-infested soils. We have rootstocks for dry areas, salty soils, high pH soils, nematode-infested soils etc.

However, grafted vines do cost more than own root vines, and for good reason - there is a lot of hand work that goes into producing each one. One of the important steps is the disbudding of the rootstock before the scion is grafted to it. If the buds are not removed, the rootstock can grow underneath the scion, and has the potential to drain some of the rootstock's reserves away from the scion, or in some cases, result in the withering away of the scion.

So one thing a viticulturist hates to see (or that I hate to see, anyway!) is something like this in the vineyard:

Here is 101-14 rootstock growing out from below ground on a Pinot noir vine. This is a case where the disbudding, which is done by a machine these days, went wrong, and a growing point was left on the rootstock of the grafted vine.

It can be difficult to spot if the machine has done a good job of removing he buds, but there's another chance to catch an error like this while the vine is in the nursery, growing the season after the graft is made.

Obviously, however, some of these devils get through and make it in to the commercial plantings.

What to do? Well, I certainly don't want them in the vineyard, so it was time to get down on my hands and knees and get rid of them. It's not as simple as pulling up the shoot, as if you do this there will invariably be some part of the shoot left, or some embedded buds will be left behind. So let the digging commence!

You need to cut the base of the shoot right out, much like you need to cut a node out on a trunk if you don't want to see any shoots arising from there later in the vine's life.

Therefore, you need to dig down to the base of the offending rootstock shoot, and use a pair of secateurs or similar to cut the shoot out, taking some of the bark and wood out from around its base. This should remove any basal buds that will be hiding in the shoot.

This picture shows where the rootstock shoot joined a vine - I used the secateurs to cut out a portion of the trunk around the base of the shoot. I leave the hole open for a day or two so that the wound can heal up in the dry and hopefully prevent any nasty soil organisms from working their way in there. Then the soil can be pushed back in.

If the job has been done right, and all the buds have been removed - no more rootstock growth. If it hasn't been successful, you'll have to do the job all over again!!

I hate digging in the soil around the vines, so I do my best to get it done right the first time!!!