Wines I'm Making: Waiting to Harvest 2011 Grapes

I did a proper test of a representative sample of grapes in our small backyard vineyard today. It seems we still need to wait. I'm nervous only because I'm afraid whatever has been stealing grapes will steal too many before I get a chance to pick. Yesterday I checked the nets carefully again and closed a few small holes. I don't know if they were new holes or holes I'd missed before.

The Cabernet grapes tested at 22 brix and a pH of 3.13. The Sangiovese, from which we will make a rosé, as usual, tested at 20 brix and a pH of 3.10. One school of thought says grapes for red wine should be picked when the square of the pH times the brix reading is around 260 and that whites grapes (or red grapes for rosé) are optimally ready when that formula yields 200. Using this method, the Cabernet grapes are at 215.5, the Sangiovese at  192. If the grapes were at the targets I usually use (the Cabernet at 24.5 brix, the Sangiovese at 22 brix), the Cabernet would be about right if by that time the pH had risen a little--say, to around 3.3. The Sangiovese grapes are closer. In any case, I think waiting is the right decision for both. So far, there is no sign of mold or other damage to the grapes, although I did notice a yellow jacket in a grape with a broken skin. Vigilance is in order. What we really need is a few days of temperatures in the upper 80s (which may be wishful thinking--the 10-day outlook is for cloudy skies and temperatures mostly in the mid-70s). The past four days of dry warmth have done little to raise sugar levels. The waiting game continues.