Cumulative growing degree days and indicator plants tell us that the onion maggot fly (Delia antiqua) and cabbage maggot fly (Delia radicum) flies are active across the state. Data from weather stations around the state show we have reached 250 GDD (Celsius, base 4C) in all regions except in the Berkshires. They are each likely to be found on or near their host crop – Aliums for onion maggot, and Brassicas for cabbage maggot.
Downy mildew (Pseudoperonospora cubensis) was confirmed on cucumber in Vineland, NJ. The current weather patterns are unfavorable for the northward spread of the disease, but with a source of inoculum near to MA it’s time to be vigilant. Watch the weather, regularly scout cucurbit fields for disease occurrence,have appropriate fungicides ready, and visit http://cdm.ipmpipe.org/ if you have internet access.
Growers throughout the Northeast need to be on the lookout for a downy mildew of basil, a disease that is relatively new to this region. This disease has the potential to cause serious losses in basil throughout New England.
Late blight has been found on tomato and potato in Long Island, and on potato in VA and DE. Given the location of the infected fields and predominately southerly winds at this time, MA growers are at moderate risk. Conventional growers should consider a preventative spray program including protectant materials, which may already be in place for control of other tomato diseases. Fields should be scouted regularly and carefully, especially in low areas in fields, wherever water accumulates, and fields where Late Blight occurred previously.
Our first confirmed case of downy mildew has been reported in Rehoboth, MA. Conditions are going to be favorable for the spread of this disease over the weekend and early next week. If you’re not already including a downy mildew specific material in your spray rotation now is the time to start, at least for crops where protecting the foliage is still important. This disease requires a different class of fungicide for good control – the materials you’re using for powdery mildew and other typical diseases may not be effective against downy mildew. Apply these chemicals in a tank mix with
On 7/18 late blight was reported on tomato in Essex county, in southwestern Ontario, Canada and also on potato in Caribou county, northern Maine. The closest incidence of confirmed late blight this year has been in Hartford County, CT in early July. The hot and largely dry weather has helped keep the disease from spreading quickly, but it is still possible that we will be seeing this disease in before the end of the season.
Regional Update. On August 3, late blight was confirmed in a home garden in northwestern Vermont near Burlington. Other new reports of late blight this past week were on potato in Maryland, New Brunswick, and Prince Edward Island. Additional new locations were found on Long Island in unsprayed tomato in gardens and in conventionally managed potato during the past two weeks. Symptoms observed on Long Island resembled drought stress than late blight, perhaps reflecting the unfavorable conditions for disease development.
When vegetable growers across New England are asked what resources they rely on most for information about producing vegetables, the New England Vegetable Management Guide is always high on their list. Updated every two years by vegetable specialists from the Universities of Maine, New Hampshire, Vermont, Connecticut, Rhode Island, and Massachusetts, it consists of 250 information-packed pages with latest on cultural practices, nutrients and soil fertility, and pest management.
Introductory sections cover:
The last Census of Agriculture conducted in 2007 showed positive trending for Massachusetts: 27 percent growth in farms both in crop and livestock sales and an increase in direct sales from farms from $42 million in 2007, compared with $31 million in 2002 -- to name just a few. The Census of Agriculture, conducted every five years by the U.S. Department of Agriculture’s National Agricultural Statistics Service (NASS), is a complete count of U.S. farms and ranches and the people who operate them.
Please see https://www.surveymonkey.com/s/late-blight for a short, anonymous survey that will help us us understand how growers are managing late blight presently, and how we might better serve their needs. The survey is primarily for farmers who grow potatoes and/or tomatoes for sale. We welcome information from farms of all sizes, and both organic and conventional management practices. The survey is anonymous and should take less than 10 minutes to complete. It can be accessed at