As we’ve talked about previously, once winter chilling is fulfilled, the rate of tree growth and development is largely dependent on temperature. This is clearly evident in the data over the last 10 years (see Figure 1). In 2012, we had an extremely early and warm spring, rapid accumulation of Growing Degree Days, and very[Read More…]
Apples
The recent spate of cool, wet weather has left one organism happy, Venturia inaequalis, the fungus that causes apple scab. Most of the state just underwent an extreme scab period, and unfortunately, few of us could do anything about it because of the combination of rain and wind. The revised Mill’s table (from http://www.fruit.cornell.edu/tfabp/revmills.htm )identifies[Read More…]
Due to the COVID crisis, all Purdue Extension meetings have been cancelled until further notice. Some may be offered by distance education, but no in-person meetings will be allowed. Most Purdue Extension staff are working from home. We are available to answer your questions by email, phone or through social media. Our contact information is[Read More…]
Growth and development in fruit crops is continuing slowly across the state due to cool temperatures and resulting low growing degree day accumulation. It’s been a rough start to spring to say the least. Frost and freeze damage from the April 15-16 events has become more obvious, and there are still risks of freezing temperatures in[Read More…]
What is the best way to assess bud damage from cold temperatures? Drs. Tara Baugher and Jim Schupp at Penn. State University have put together a nice page with some excellent photos explaining how to assess fruit bud survival: http://extension.psu.edu/plants/tree-fruit/news/2016/assessing-fruit-bud-survival-and-crop-potential I would add that unless you find that more than 90% of your buds have[Read More…]
Over the last week many areas of the state have experienced minimum temperatures likely to cause bud damage. Many areas experienced low temperatures of 24-26 F (according to weather stations) although one grower reported a low of 22 F. As experienced growers know well, it’s not just the temperature as such that’s important, but the[Read More…]
Apples in Lafayette are approaching pink. IN more southern areas of the state apples are past full bloom and into petal fall. Frost damage to crops has been widespread in southern areas of the state. Fruit crops are in early stages of growth across the state. In southern areas peaches and apples are in bloom[Read More…]
Due to the COVID crisis, all Purdue Extension meetings have been cancelled until further notice. Some may be offered by distance education, but no in-person meetings will be allowed. Most Purdue Extension staff are working from home. We are available to answer your questions by email, phone or through social media. Our contact information is[Read More…]
“Timing is everything.” No truer statement has ever been uttered, especially in the orchard, where the timing of fungicide sprays from “pink” (bud stage) through petal fall requires an almost psychic ability to anticipate pesticide timings. Abundant ascospores production occurs at pink and continues through petal fall, increasing the risk of infection until petal fall[Read More…]
It can be useful to compare this growing with previous years. The typical way we calculate growing conditions is by calculating Growing Degree Days (GDD). This is somewhat similar to the method many are familiar with for calculating codling moth emergence. In Figure 1, we see the accumulation of GDD over the last 10 years.[Read More…]