Fungicide Timing, Rapid Corn Growth & Soybean Challenges

July 2, 2025 Edition

The 2025 growing season continues to challenge us, but our fields are progressing — and we’re seeing several key trends emerge across our trade territory. Here’s what our agronomists are observing this week, along with recommendations to help keep your crop on track.

The corn crop around the region has pushed through a wild June. Most fields are now at V7 to V10, and some are nearing the stage where we say, “it’s too big to spray.” If you haven’t already applied post-emerge herbicides, your window is basically closed. A few scattered fields might still be okay, but for most, the cutoff point for safe herbicide use has passed. That means: what’s out there in terms of weeds is likely staying.

Now comes rapid growth stage. Corn is taking off — what was knee-high last week could be shoulder-high by next week if heat sticks around. Tasseling isn’t far off.

Disease Alert 🚨

With all the recent moisture and high humidity, we're entering a stretch of prime conditions for disease development. Tar spot was confirmed in our area late last season, so while we're not sounding the alarm just yet, it's definitely something we’ll want to monitor closely as the season progresses, and you should have a clear-cut plan for.

Fungicide Strategy: If your field has good yield potential (no drown-outs, good stand), a tassel-timed fungicide can be a game-changer. We recommend using:

You’re already going across the field — make it count.

Soybeans have been through it: excess moisture, hail, wind, and cool temps. All that leads to yellowing, slow growth, and patchy stands. Some areas have even had stand loss, which can delay canopy closure and increase weed pressure.

We’re starting to see R1 (first flower) in many fields. That means:

Weeds Aren’t Done Yet

Killing weeds in this environment has been tough. A strong Liberty or Enlist + Roundup mix with full adjuvant load is going to be your best shot at clean fields. Don’t skimp on:

Cutting corners on adjuvants now = tough weeds later. Kill them while you still can. Using a high-quality adjuvant is our #1 recommendation we can give to you. 

Small grain acres are limited, but where they’re growing, they look solid. If you didn’t apply fungicide at flag leaf or flowering, it might be too late — but if the crop isn’t flowering yet, you may still have time to protect yield. Keep scouting! Aphids have been seen just across the border in SD, and they can show up quick.

Alfalfa is often the forgotten crop — but it shouldn’t be. There’s a perfect storm of:

Better Feed. Better Beef (or Milk). It all starts here. These issues are hitting tonnage and feed value hard. Scout your fields! Even a small investment in insecticide, fungicide, or foliar nutrition can add value and pounds per acre.

This season has already thrown us hail, wind, waterlogged fields, tornadoes and delayed growth. Some crops are looking great — others are barely hanging on. There’s no one-size-fits-all answer right now, and every field is different. That’s why your relationship with your agronomist matters more than ever.

A common question we’re getting: "How long can my crop survive in standing water?”

Answer: It depends. Stage of growth, duration, and air/soil temperature all matter. But the longer a crop is submerged, the higher the risk of yield loss.

We also know some growers can’t get a ground rig in. Crop care by air is a solid alternative. Aerial applications may not be perfect, but they can help knock weeds back and keep the rest of the crop growing.

👉 Tough conditions call for tough choices — and timely decisions. Let’s make the best of it.

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