In Michigan we have used approximately 284 DD42 from March 1 as the start point for king bloom on Macs. This is in our Michigan State University Fruit Management guide E-154, from a chart originally prepared by Phil Schwallier of MSU. This is based on pre-1990 weather data in the Grand Rapids area of Michigan.
In recent years we have been getting more DD before March 1...so ignoring what happens before Mar 1 is now becoming problematic. So, I generally add on 25 DD42 to the total and use a target of 310 DD42 from January 1 as the start point for king bloom for Macs. Not sure if this works for your area. 1/2" green is approx 205 DD42 from March 1, or 230 DD42 from January 1 with my fudge factor. Bill Shane On Wed, Mar 31, 2010 at 9:18 AM, William Sharp <[email protected]> wrote: > I am In the Shenandoah Valley of Virginia and we are about 1/2" green tip > (or a little further) on Red Delicious. It is supposed to be quite warm the > next couple of days and I am trying to predict when apple bloom may be i.e. > will it be within the next week. Does anyone have info on using DD to > predict bloom? > We are not yet at bloom on peaches, but I expect it to start tommorrow.. > > Bill Sharp > -- Bill Shane District Extension Educator SW Mich Res & Extension Center Michigan State University 1791 Hillandale Rd, Benton Harbor, MI 49022 269-944-1477 x 205; 269-208-1652 cell
