This vintage is pretty amazing. We’ve had no pressures like rot. The canopies are open and healthy. Shoot sizes are in balance. The crop level is slightly low and there is a nice display of fruit.

We have had ideal weather, with temperatures from the high 70s to low 90s, mild nights and adequate humidity (low humidity can hurt us more than heat). All the shoots are lignified (turned brown and woody), the seeds are starting to ripen, and the year has progressed very nicely so far.

This has been a dry growing season, and the soils have dried up quickly. In block 190 at Donum, for example, we dry farmed and didn’t irrigate last year until the end of harvest. After three years of cover crops using up water there, the vigor of the vines has been controlled. Now the neutron probes show that the soil is dry to the bone. There is no reserve in the ground and beginning today, we expect several days of temperatures near or at 100 degrees.

The old wisdom was that you stop irrigation and stress the vines to concentrate flavors before harvest. There was an almost romantic notion that stress could create character in the grapes. Next we began thinking in terms of a water deficit management curve, where we tried to provide just the minimum amount of water for the vine to function.

According to Dr. Phil Freese, our viticultural consultant, research has now shown that after the grapes reach 20 degrees Brix sugar level, you can replace water to an evapo-transpiration level of 100% (calculated using a grape crop coefficient) without changing the sugar, pH or total acidity values.

By not stressing the canopy and providing the water it needs to function in a healthy manner, the vine will attain ripeness levels by producing sugar and not as a result of dehydration. And with the vine functioning during “hang time,” we may get full ripeness at slightly lower sugars.

Now our thinking is that it’s better to provide a little extra water rather than not enough. In practice, we take leaf water pressure readings to provide us with a snapshot, like taking blood sugar, of the vine’s condition right now. If the need is indicated, we’ll provide small doses of water, about five gallons each, then take another reading in three or four days and adjust accordingly. We have to maintain a healthy, active canopy right into harvest, because we often get levels of heat that they never experience in Europe.

For those who would denigrate our drip irrigation, citing the European model, we remind them that in Europe they often receive 10, 15 or more inches of rain during the growing season, and in some famous locations, their vines are “dry farmed” where the water table is just a few feet below the vineyard.

Once again, the individual characteristics of the site totally determine the appropriateness of particular viticultural practices.

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