Spring 2025 has brought a mix of hot, dry, and windy weather across much of the Prairies. Many areas are experiencing lower-than-ideal rainfall, which is beginning to influence crop development.
Grasses are pushing out seed heads earlier than usual. Prolonged heat and limited moisture can stress plants and lead them to enter their reproductive stage sooner, which often results in an earlier harvest window.
Under typical conditions, tall fescue is swathed in mid to late July, perennial ryegrass from late July to early August, and timothy in early August. However, current crop development suggests that more swathing could take place in late July than usual.
If cooler, rainy conditions arrive during July, growth may slow down slightly. This can actually benefit the crop, especially as grass seed heads are pollinating and filling during this period. Having adequate moisture is important for that process.
How to Know When It’s Time to Harvest #
Harvest timing on grass seed production crops can be tricky. A lot of knowing when it’s the right time comes from experience growing the crop and recognizing the signs. For newer growers, it can be intimidating not knowing exactly what to look for when the crop might be ready to swath. If it’s done too early, you could lose bushel weight or seed quality. Too late, and seed shatter losses start to add up. Your local Seed Production Specialist is there to help figure out the best time to get started.
There are a few signs to watch for when your seed crop is getting close to swath timing. One of the easiest to spot is a colour change. When your fescue or perennial ryegrass starts turning more of a tan shade, that’s a good sign you’re getting close. For perennial ryegrass specifically, you can grab a few seed heads and shake them into your hand. If the seed shatters fairly easily and most of what lands in your palm is tan-coloured, the crop is likely ready. A few green seeds are okay, but if most of the seeds are still green, it’s not quite there yet.
If you think the crop might be ready, doing a test cut can help. If the stubble is mostly tan or whitish, it’s probably good to go. If the stubble is still mostly green, give it a bit more time to dry down.
In tall fescue, seed heads will ripen and you’ll start to see the stem just below the head change colour as well. That’s a helpful indicator it’s getting close to swathing.
For timothy, watch for “tipping”—that’s when the tips of the heads start shelling seed, leaving a thin core poking out from the top. Once that starts happening, it’s a good sign the crop is ready to be swathed.
| Crop Species | Signs of Maturity | Swath Timing | Harvest Timing |
|---|---|---|---|
| Perennial Ryegrass | – Crop is tan in colour – Seeds shatter easily when shaken into palm – Mainly tan/ripe seeds – Tan/white stubble when cutting | Late July – Early Aug | ~ 7 days after swathing |
| Tall Fescue | – Crop is tan in colour – Mainly tan/ripe seeds -Stem below seedhead is tan in colour | Mid – Late July | 5 – 7 days after swathing |
| Timothy | – Crop is tan in colour | Early Aug | 5 – 7 days after swathing |
These crops will remain in the swath for about seven days (weather dependent) before they see the combine.
Tips for a Successful Seed Production Harvest #
- Utilize your Seed Production Specialist for support! They will help you determine proper harvest timing and can help with combine settings.
- Swathing at night or early in the morning can help reduce shatter losses.
- Crops can change a lot in a day. When it’s getting close to swath timing, keep a close eye on your field so you don’t miss the ideal window.
- After harvest, monitor crops in the bin and use aeration when needed.
Thinking Ahead to Stand Establishment #
Success begins with proper stand establishment. You can start preparing now to get your stand in the best shape possible for it’s first year of seed production. If you have seeded a stand this spring, plan in the fall to apply fertilizer; this helps the stand take off more quickly the following spring. When harvesting the companion crop on your stand, leave eight to 10 inches of stubble to allow for the best chance at snow capture and overwintering success. Thinking about planting next year? Try to get your field as clean as possible beforehand to minimize problem weeds in crop and reduce competition for your new stand.
To learn more about producing seed with BrettYoung, click here.
