Grape growth is a bit ahead of normal this year. Grapes are at the critical 1 to 3 inch shoot length when Phomopsis cane and leaf spot infections occur. This is a critical time to take control measures for this disease. If left unchecked, the early shoot infections will spread to cluster stems and developing[Read More…]
Grapes
The 2016 Midwest Fruit Pest Management Guide (ID-465) is available for purchase from the Purdue Education Store. This publication replaces two previous annual publications: The Midwest Tree Fruit Spray Guide (ID-168) and The Midwest Small Fruit and Grape Spray Guide (ID-169). This guide provides pest management recommendations for commercial tree fruit, small fruit, and grape[Read More…]
There has been some talk about the use of promalin to help overcome the damaging effects of freezing temperatures. Only a small amount of research has been conducted on this. Dr Steve McArtney showed that promalin applied after damaging freeze events could increase parthenocarpic (seedless) fruit development. Keep in mind this was only shown to[Read More…]
As the spray season approaches, it is good to remember the profound impact water quality has on the performance of pesticides used by fruit growers. Purdue Pesticides Program recently published a guide, The Impact of Water Quality on Pesticide Performance PPP-86, available at the Education Store, 1-888-EXT-INFO or www.extension.purdue.edu/store/. I highly recommend this guide to[Read More…]
There are some potential pest and disease problems that require early season sprays. Phomopsis is a major problem on many grape varieties in the Midwest. Mancozeb should be applied starting at 1-3 inch shoots and repeated each 7-10 days, especially prior to a predicted rain event. Colleagues in Michigan and Ohio have been conducting evaluations[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…]
Frost and freeze damage was minor in small fruits and grapes. Below is a review of general guidelines for when we expect damage to buds, flowers and fruit. Developmental stage 10% kill (°F) 90% kill (°F) Apples Silver tip 15 2 Green tip 18 10 Half-inch green 23 15 Tight cluster 27 21 Pink 28[Read More…]
Early spring is a good time to make the first herbicide application of the year. There are several options for grapes, brambles and blueberries including both pre and post-emergent herbicides. In most situations, there will be some emerged weeds present in the planting at this time of the year. That means a post-emergent herbicide will[Read More…]
Spring freeze damage can be a significant economic problem for Midwest grape growers. Widespread damage occurred in 2007 and 2012 when warm temperatures in March were followed by freezing temperatures in April. Obviously this year we have had a warm February and March so it is very possible that we will have early bud break[Read More…]