Spring Oats Seeding Date: Seed Spring Oats in March?

As winter is becoming more unpredictable by the year, whether it is cold in December, record warm in February, or moisture levels well above or below average, what remains predictable is farmers wanting to get started early. Farmers eagerly await the arrival of the growing season, especially in the state's southeast. When the weather provides, should farmers take advantage of early spring to seed spring oats in early March?

To answer this question, let's go over some basic information about oats, list some research findings on spring oats' seeding date, and then we can reach a conclusion with some level of confidence and peace of mind.

Agronomics of Oats

Oats are cool-season annuals for forage or grain production. They grow rapidly at cool temperatures and reach the milk stage 55–65 days after germination. Spring oats can tolerate light frosts but won't take a harsh freeze. Interestingly, the time of oats' establishment can affect their ability to withstand cold. Late summer or early fall-seeded oats can be killed by several hours of temperatures below 27°F. Spring-seeded oats, which are often more tolerant, are killed when the temperature drops below 5°F. Spring oats need soil temperatures of at least 35°F to germinate. Still, higher soil temperature (above 45°F) will accelerate germination and promise a vigorous stand. Even though oats are a cool-season crop, the yield will suffer when the temperature drops to 65°F or lower.

Optimum Planting Date

Researchers from different states studied the optimum seeding date for spring oats. The Ohio State University research recommends early April as the optimum seeding time. New York research shows that the optimal planting date was April 18 and suggests that for each day past the optimal date, the average yield decreases by about 1 bu/acre. In southern Ontario, early April seeding had a lower plant population, higher yield, an earlier heading date (5 days earlier), and a longer vegetative period compared to late April-early May seeding.

For Pennsylvania, April 15–May 10 are the usual planting dates for spring oats. Research has shown that spring oats yield decreases by approximately 1 percent per day when seeding is delayed beyond the optimum seeding date. How to know the optimum seeding date for spring oats? The best way to determine the optimal seeding date is to check soil temperature in the seeding and root zones for oats (1.5 to 2 inches). It should measure at least 45°F and remain consistently warm for at least 2 weeks before seeding. Soil temperature can be checked with any thermometer that reads 30 to 65°F.

Concerns When Seeding Early

When we seed spring oats earlier than the recommended optimum dates, we must pay close attention to several factors.

• Weather conditions can change sharply during a Pennsylvania March. Oats seeded in spring are relatively tolerant to cold conditions compared with other species; however, they can still have damage leading to yield drag. Cold weather, right after extended periods of warm weather, can kill the rapidly growing, recently germinated oats stand. This injury can lead to yield loss through a decreased population, tillering capacity, or even a stand failure. The earlier the crop is planted in March, the higher the possibility of adverse weather conditions.
• Early spring is usually accompanied by soggy soil and fungal development. If the soil is not well-drained and the seed doesn't get enough oxygen to germinate, seed rot can occur. The newly developed roots can be rotted in wet soil, even after germination. Lower soil temperature, which slows spring seedling growth, can exacerbate fungal issues in newly established oats.
• Oats planted earlier than usual will mature earlier than usual. How many days earlier is variable, depending on late spring temperatures and oats cultivars, but farmers must consider how harvest time fits with other farming operations. Earlier maturing oats can be beneficial if the operation is in a double-cropping system. If the oats are used as hay or silage, drying to the correct moisture content can be challenging. Frequent spring showers, with consistent wet soils, can prohibit the matured spring oats harvest at the right growth stage or moisture, potentially reducing forage quality.

Summary

All in all, it comes to the risk-to-reward ratio for all the decisions we make for agriculture. Research may show that April 15–May 10 is the optimal planting range for Pennsylvania, but this is 10-year-old data that doesn't account for climate change or farm-specific needs. Research provides a starting point. If you want a planting date more specific to your farm:

1. Monitor the soil temperature (not air temperature) until it is consistently above 45°F for at least two weeks.
2. Determine when the soil is workable without excessive moisture.
3. Be sure that early-maturing spring oats can be harvested on time with the weather patterns in your location.

Starting in March, farmers should monitor fields, inspect and maintain necessary equipment, and ensure seed and field treatments are on hand. If the conditions go in the right direction, seeding spring oats can happen quickly.