I’ve continued to take notes and track the 2008 season, which thus far has had as its “defining moments” severe frosts at the end of March and again during the third week of April.

Monday, May 5th:
Today Nabor and I stood in a low bowl on The Donum Estate and took in the vineyard landscape. He observed that while cold air normally flows in from the north, it came instead from the south during our recent frost, flowing like water and reaching a fairly high level in this bowl. Once it hit the hillsides, the cold air had nowhere to go but up.

Normally we see differences between vines up on ridges and those down in the swales. Water drains from the ridgelines quickly, and due to their elevation and exposure, vines up there are in warmer as well as drier conditions. But with something like 30 nights of cold weather this spring, the variation is more pronounced. The bowl was affected by continual cold air as well as by two nights of frost.

As we looked around, the vineyard reminded me of the visual effects of flood waters. We could see a frost line. Nabor pointed out that even on individual vines, lower points were damaged while higher points were unaffected. We saw considerable variation in shoot maturity on single vines, and that can be problematic. We can only hope that the vine will compensate and even out its maturation as the season progresses.

Even vineyards with wind machines or overhead sprinkler irrigation for frost protection had problems this year. During the last frost, we had wind machines go on at 11 pm and run until after 6 in the morning. In one instance, the temperature dropped so fast that the gas apparently froze in the line, and the little computer on the wind machine displayed a “help” message.

The fans on wind machines are usually at a height of 40 feet so that they can move air from a warmer layer down to ground level. This time the air was so cold that the fans just moved more cold air.

Usually sprinklers provide the best protection, but not if they run out of water, and some growers have used up their water supply. Micro-sprinklers have such a low flow rate that those lines also froze.

Most of our blocks have cane-pruned vines, which are more flexible, but some say they were hit harder than cordon-pruned vines. With severe cold, the sap recedes. Alternating cold and warm weather can also put the vine in shock. Nabor cut a cane where the shoots were withered, and it was dry. Then he cut a sucker off of the same vine’s trunk and it bled sap. We’re sure the trunks and roots are ok.

We’ll keep shoots even though they appear to be too far behind, because we want to leave growing points and keep the vine in balance. I don’t want to create a few huge canes. We don’t want to rub off damaged buds because they contain back-up systems; there’s still something there that wants to push.

We drove maybe 150 feet to the top of a ridge, and the vines on the crest were really green. Over that short distance, it’s as if we had moved ahead a month in development. In this nice weather, these vines are moving nicely and are close to flowering. I expect bloom in the next two weeks.

Many of our blocks look good. We’re ok and we’re coming back. I expect we’ll get as high as ten clusters (about two pounds) per vine, and that translates to about one ton per acre for those vines with frost damage, whereas undamaged vines normally would produce four to five pounds per vine.

As we looked around from atop the ridge, we saw a lot of green. To a grower, green means growth and that means hope. Nabor said we have to recharge our mentalities. He told me his new computer password is “hope.”

Friday, May 16th:
We’ve had three very warm days in a row with temperatures from 99 to 102 degrees F. The nights have been very warm with a hot wind blowing. Suddenly we are seeing an explosion of shoot growth and the internodes (distance on a shoot between nodes or areas where lateral shoots develop) are extended. It’s as if the vines are on steroids.

In Carneros, the Martini Pinot Noir selection is farthest along in flowering. Lots of calyptra (little caps of fused petals) have come off. Flowering may have been too fast and could affect fruit set. We’ll see.

Our 290 and 390 blocks, hit by frost, are still behind but catching up. Even where there was no frost but the vineyards were cooler longer – in the swales and flats – there is diminished growth, but they are gaining on the vines on the ridges. Overall, the vines are not as uneven as we had expected. If flowering moves along quickly, we’ll see how much the vines have evened out by veraison (when grapes soften and turn color).

We had a dry spring and our probes showed that the soil profile was pretty empty, so we put on water. We’re glad we did, because this heat has not stressed the vines. We have enough water, and we’ll need to stay on top of that situation this year.

I walked the vineyards early today. It was a gorgeous morning with the light playing on the rolling hills and a hot air balloon drifting by. The vineyards look healthy, and I feel very positive. Green is back!

Friday, May 30th:
I visited our Russian River Valley vineyard on Wednesday. The vines looked good – everything has come back since the frosts. We may just get growth and not a lot of crop from secondary buds that pushed out after the primaries were damaged. We’ll see.

Both there and in Carneros, the brief heat spell in mid-May tightened the period of flowering. Within a week, we went from 5% to 100% bloom. I walked our Donum Estate vineyards on Tuesday, and I observed that flowering is finished and the grapes are starting to set. Lateral shoots are pushing out and the vines are moving to the wires. Again, it will be hard to say what we have in terms of crop until the berries size up.

The cool Memorial Day weekend, which included a few hours of modest rainfall on Saturday, has persisted through this week as cloudy mornings are followed by sunny afternoons. As we see more green, we also see less unevenness, and that remains cause for us to be positive.

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