Replant problems and possible solution

Years ago I read that some vintners have problems with replanting individual vines. I now share this experience: one position at the bottom of the Grenache has been 0/3 (original died along with two replants), and another replant at the top of the Syrah has taken but is stunted.

The entire bottom Grenache row is weak and has never been harvested (vineyard is 9 years old). I thought the row suffered from afternoon shade from a large oak, but my vineyard guy suggested that roots from the tree could be the problem. I didn’t think so, as the row is 15’ from the tree’s drip line. But this weekend digging the hole to prepare for replant 3 sure enough there were roots coming from the oak’s direction - stealing water from the vineyard’s drip system. This explains the bottom row’s weakness as well as the problems with prior replants.

I plan to dig a 3-4’ trench below the bottom row and bury some kind of root barrier. But I have 3 Grenache to replant now, so I plan to put them in biodegradable “pulp pots” - then into the ground. Hopefully the pots will allow the baby vines to get strong before roots from nearby trees or adjacent adult vines steal their water (and possibly also prevent growth by plant to plant inhibition).

This got me thinking about the Syrah replant at the top, which though planted 3 years ago and given an extra drip emitter failed to grow. I decided to see if adjacent vine roots could be the problem, and dug two narrow trenches between the baby and adjacent adult vines. Sure enough there were large roots coming in - including some 1/2" ones probably from a landscape shrub 10’ away (red tip photinia).

After digging through the roots I stapled a bare copper wire to inhibit new root growth:

Then I lined the holes with plastic to prevent re-growth (from a garden waste bag)

Then buried everything, trimmed the plastic edges, added a bit of fertilizer, and gave baby a big drink

Now with fingers crossed let’s see what happens this season

Thanks for posting this. What is the function of the copper wire? Never heard of this measure.
I’ve had better luck replanting with Ubervines from Duarte than I ever had with regular dormants or green-growing, but I can’t say anything I’ve tried has been worth the effort.

I rented a Ditchwitch and trimmed the oak roots back to their dripline today. That gives the vines at least 10’ of no-compete zone. I had about 450’ along the edge of the vineyard where the vines were getting outcompeted by adjacent trees. It had been about 15 years since the last time I had done it, and that was probably 10 years too many. I got a ride-on version and would strongly recommend that sort of mass. It made quick work of a 40" deep slice through a whole lot of oak roots up to 2-2.5" in diameter. I had thought of dropping in some sort of plastic barrier, but the hassle involved, contrasted with the ease of this job, made me think that just cutting this trench on a more regular basis was the more efficient approach.