Crack the Code on the Blue River Hatch

Blue River
Hatch Chart 2025

From tailwater midges to summertime hoppers, the Blue River makes you earn every take. Fish smarter with our full hatch chart and fly matching tips.

The Blue River tailwaters are legendary for their consistent hatches. Whether you're nymphing below Green Mountain Reservoir or swinging dries near Silverthorne, knowing when insects hatch is crucial. Use our refreshed 2025 Blue River hatch chart to time your trips, select the right flies, and fish confidently month by month.

Hatch Charts

Know what’s hatching, when it’s happening, and what flies to tie on—month-by-month intel from the heart of Colorado trout country. Hatches by month and type are below. 

 

2025 Blue River Hatch Chart: Crack the Code on Monthly Fly Hatches

The South Platte River is Colorado’s overachiever: part tailwater, part freestone, all attitude. From Cheesman Canyon’s spooky trophies to Deckers’ weekend rodeo, this river makes you earn every trout—but man, does it pay off. The fish are smart. The bugs are picky. And if you think you can just toss any old fly out there, well… better pack a lunch.

That’s why knowing the hatch matters. Below is a month-by-month breakdown of the most reliable bug activity on the South Platte, plus our top fly picks for matching the hatch. Whether you’re stalking sipping rainbows or dredging for grudging browns, this chart is your river-side cheat sheet. Blue River fly hatches tailwater are a gem. Blue River Silverthorne hatch timing is tricky so download our hatch chart and have them at your finger tips. 

 

View the Blue River Fly Fishing Report Here. 

South Platte River Hatch Chart – By Month
South Platte River Hatch Chart by Month
Month Main Hatch Secondary Bugs Tertiary Bugs Guide Tip
January Midges (#20–#26) Winter Stoneflies Micro BWOs Slow drifts, long leaders, light tippet. Fish deep.
February Midges (#22–#26) Stoneflies Micro Baetis Pair midges with egg patterns. Trout stay low.
March BWOs (#18–#22) Midges Early Stones Cloudy days = swinging soft hackles goldmine.
April BWOs Early Caddis Midges Focus on pods of risers. Delicate dry fly work.
May Mother's Day Caddis BWOs Early PMDs Skittering caddis and emergers dominate the hatch.
June PMDs (#16–#18) Caddis Yellow Sallies Dry + emerger combos are deadly in pocket water.
July Tricos (#20–#24) Caddis Hoppers Start early. Switch to terrestrials after the spinner fall.
August Tricos Ants, Beetles, Hoppers PMDs Prospect with a beetle + midge dropper mid-morning.
September BWOs Fading Tricos Late Caddis RS2s and emergers shine on cloudy fall afternoons.
October BWOs Midges Streamers Start with dries. Switch to meat if the clouds roll in.
November Midges BWOs Eggs Mix midge nymphs with an egg pattern for depth.
December Midges Winter Stones Baetis Drift small midge larvae slow and deep in tailouts.

 

Learn the Bugs, Land the Fish

Matching the hatch doesn’t mean being a bug nerd (though we fully support it). It means noticing size, silhouette, and how those little guys behave in the water. Presentation > Perfection. Want to fish better tomorrow? Start by tying one better knot today.

Fly Pattern Cheat Sheet Table
Month Hatch Type Best Flies Sizes
January Midges Zebra Midge, RS2 20–26
April BWO Sparkle Dun, Juju Baetis 18–22
June Caddis, PMD Elk Hair Caddis, Barr’s Emerger 14–18
August Blue-Winged Olives Sparkle Dun, BWO Spinner 18–20
October Midge & PMD Zirdle Midge, RS2 Emerger 20–24
FAQs About Blue River Hatches in 2025
  • Q: When do Blue River midges hatch most consistently?
    A: Midge activity on the Blue River is strong from January through April, especially early in the morning and late afternoon.

  • Q: Where does the Blue River have the best flows for hatches?
    A: Tailwaters below Green Mountain Reservoir and six-mile canyon near Heeney offer year-round hatches, thanks to stable flows.

  • Q: Should I fish dries or nymphs on the Blue River?
    A: During peak hatches (May–July), dries like Sparkle Duns and Juju Baetis work best. In winter and early spring, midging with nymphs like RS2 and Zebra Midge is more effective.