Final weekly vegetable update of 2021 9/15

Crop updates 

• Cucurbits: It seems like all of the winter squash is ready all at once this week. Every year I get a few photos of squash with sunscald. Symptoms can range from round spots to general discoloration on the upright surface, especially in lighter skinned squash. Keep in mind that fruit that have been exposed to direct sunlight in the field due to powdery mildew or other vine die-back are more susceptible, and that curing should happen in a shady place to avoid exacerbating sunscald. Read more about curing squash and pumpkins here.
• Cole crops: This fall has been ideal for cole crops, with cool nights and warm (but not too warm) days. I'm seeing so many beautiful photos of radishes lately! We may start to see splitting in radishes in areas that receive substantial rainfall in the next couple of weeks; consider harvesting a bit early if a major rainfall event is predicted in your area. This has also been ideal head-setting weather for broccoli and cauliflower, and with fewer disease problems than normal, it's turned out to be a great year for these crops.
• Tomatoes and peppers: This was a big week for tomatoes and peppers. For growers who had sufficient access to irrigation, this has been one of the best tomato and pepper years in recent memory. These crops are putting out their last flushes before winding down with the cool weather.There still has not been a late blight detection in the state, and most other common disease problems have been minimal. 

The hottest, longest season peppers are coming into maturity. Photo Lindsey Miller.

• Garlic: Growers in Northern Minnesota can start to think about planting in the next week or so. Growers in the Southern part of the state should wait about 3 weeks. To get you in the mood for garlic planting, I highly recommend checking out the recent episode of the Vegetable Beet: The garlic guru - From clean seed to scaping.
• Sweet corn: As sweet corn harvest nears its end, corn earworm trap counts remain above the threshold across the state.
• Carrots and beets: During my farm visits in the past week I've seen some of the healthiest, best stands of beets and carrots that I've ever seen.We're seeing a bit of Cercospora in beets, and some aster yellows in carrots, but for the most part these issues are sporadic. Despite the season long drought, the heavier rains in the last few weeks may mean harvesting root crops will be a bit challenging for growers with heavy soils. 

Photo: Lindsey Miller

Vegetable weather report

Around one inch of rain is projected for most of the state this week, with more like 0.1-0.25 projected for a pocket of Western Minnesota ranging from around Montevideo to Grand Forks. The US drought monitor still shows most of Northern Minnesota in extreme drought, with a pocket of exceptional drought spanning Red Lake. But, the drought in much of the state continues to lessen in severity. Nighttime temperatures are still not projected to reach freezing within the next 10 days or so, even in the far northern part of the state.

7 day precipitation forecast, weather.gov

This is the last weekly vegetable update of the season, but you can continue to monitor the drought and learn about Minnesota weather and climate through the UMN Extension Weather Talk blog.

Problems in the field and things to anticipate this week

New soil health resources

As the end of the season rolls around, it's a good time to reflect on what's working well, and new practices you'd like to try. When we conducted our needs assessment in 2019, Minnesota fruit and vegetable growers identified soil health as their top priority for research and outreach. So, we've been slowly building a collection of tools and resources. The first is a new section on our website dedicated to soil and foliar testing, nutrient management, reduced tillage, and cover crops. 

One thing we're learning (and will post more data about this winter) is that many vegetable farms are over reliant on manure as a fertilizer source, and this is resulting in sky high phosphorus levels, as well as soluble salts. Fall is a great time to get a soil test, which can help you understand nutrient concentrations in your soil. Our team is available to help you navigate nutrient management decisions this winter. Check out the video below to learn about soil testing on diversified vegetable farms, including how often to test, which tests to do, and when to combine samples vs. test fields separately.

Staying connected this winter

As we transition into fall, our team is planning a variety of events, and participating in a number of conferences. Winter can be long and lonely, so these are great opportunities to stay connected to fellow growers and to get new ideas for next year. Stay tuned to our newsletter for more information; here's a sample of events to come:

• An online farmer to farmer discussion series about resilience to climate change (and resilience in general) in collaboration with LSP. This is a continuation of our farmer to farmer event series from 2019 and 2020. If you missed these last year, you can check out the virtual field days from 2020 that were the foundation of our winter gathering discussions. We'll use a similar format this year, with virtual field days (20 minute videos) followed by Q&A with the farmer, and a farmer to farmer discussion.
• Online grower gatherings to discuss how the season went. These will be crop specific. We for sure plan to do this for pumpkin growers and broccoli growers this fall, but we're open to suggestions if folks want to do this for other crops as well. 
• The Organic Vegetable Production conference (usually held in Madison WI) will be online this year.

Technical assistance

 If you're seeing interesting things in your fields, need help identifying problems, or just want to share photos, we'd love to hear from you! Growers can reach out directly to me any time at hoida016@umn.edu, and you can submit questions and requests for diagnostic help here.