At this point in the season, and for simply patching up on grade, I'd opt for sod.

Annual Rye is ugly as heck and doesn't always die without some help.

 

^ +1 You're also very late to be planting KBG. You'll need about 60 days before your average first frost date for it to germinate and establish. Depending on the variety, you may not see germination until end of the month/first week of October. That won't give you enough time.

I would either sod this Fall or plant PRG or TTTF or a mix of both with the intent of killing it off next July and getting your seed down by the end of August, latest. Ideally mid August. That seems like a lot of work and a waste of time and money, but you will have much better success if you start the process earlier.

 

Thanks, @Harts and @Sinclair .
Its too hot here to plant much before the end of August. Our first frost is late October, sometimes early November.
KBG winters pretty good here, we can get some sub zeros, but its usually just shorts spells, and mostly in the teens (F) or above.

I was able to start some ShureShot KBG from United Seed on September 17 last year and it did great. Admittedly that was a later start than desirable. I used a straw blanket with nylon mesh backing for that. It worked well, but I think it brought some weeds with it, and there are still places I can see the mesh.

I had peat down for this years project (different area), but it keeps getting washed away in the rain storms.

I'm going to have to put some more seed down now. Maybe I need to go back to the blanket.

 

You know your climate better than I do. If you think you can get KBG down and established, go for it. I would mix PRG thought, not Annual Rye.

 

Thanks, @Harts and @Sinclair .
Its too hot here to plant much before the end of August. Our first frost is late October, sometimes early November.
KBG winters pretty good here, we can get some sub zeros, but its usually just shorts spells, and mostly in the teens (F) or above.

I was able to start some ShureShot KBG from United Seed on September 17 last year and it did great. Admittedly that was a later start than desirable. I used a straw blanket with nylon mesh backing for that. It worked well, but I think it brought some weeds with it, and there are still places I can see the mesh.

I had peat down for this years project (different area), but it keeps getting washed away in the rain storms.

I'm going to have to put some more seed down now. Maybe I need to go back to the blanket.

I started a KBG section with temps 95F+ and it germinated fine. How hot does it get up there in canada?

 

Is there a downside to planting Annual Ryegrass with KBG to help with erosion while waiting for the KBG to germinate?
I'm patching some areas that are on a grade.
Would the Annual Ryegrass die out and leave me with just the KBG? That's what I'd like.

Yes, there are major downsides to planting annual ryegrass with KBG. The annual ryegrass will not all be as easy to selectively eliminate as is commonly thought. Also, the annual ryegrass will compete with the KBG starting as soon as it germinates and impede the development of the KBG you are trying to grow!

My personal perspective is to only plant that which you want to be there long term. If you want an eventual lawn of only KBG, then sow only KBG seeds.

If you need to deal with a severe erosion issue on a slope, do so through seeding blankets, tackifiers, non-seed-carrying mulches such as PennMulch or even hydroseeding. However, planting some other type of grass along with the KBG will cause more pain than gain.

 

I'm not in Canada, I'm in central ohio.
I don't have irrigation, so its pretty hard to keep it wet with temps in the 90's F.

 

Is there a downside to planting Annual Ryegrass with KBG to help with erosion while waiting for the KBG to germinate?
I'm patching some areas that are on a grade.
Would the Annual Ryegrass die out and leave me with just the KBG? That's what I'd like.

Yes, there are major downsides to planting annual ryegrass with KBG. The annual ryegrass will not all be as easy to selectively eliminate as is commonly thought. Also, the annual ryegrass will compete with the KBG starting as soon as it germinates and impede the development of the KBG you are trying to grow!

My personal perspective is to only plant that which you want to be there long term. If you want an eventual lawn of only KBG, then sow only KBG seeds.

If you need to deal with a severe erosion issue on a slope, do so through seeding blankets, tackifiers, non-seed-carrying mulches such as PennMulch or even hydroseeding. However, planting some other type of grass along with the KBG will cause more pain than gain.

Thank you!!
No Annual Rye for me.

 

@badtlc despite what my classmates when I went to college in Virginia thought, it does not snow all year round

July and August gets into the 90s consistently, we'll over 100 with humidity. We have days when it's hotter here than many parts on the south.

The downside is we have a long winter, spring and fall. I like it hot. Hate the cold.

Mid August for Ontario is the perfect time to seed. Temps may still be high 80s, low 90s but the days are shorter, the sun is lower and watering frequently cools the soil down.

 

You'll need about 60 days before your average first frost date for it to germinate and establish. Depending on the variety, you may not see germination until end of the month/first week of October.

Realize this is a bit OT but seems like OP has his answer so this seemed like a good opportunity to ask.

I always see 2-3 weeks suggested for KBG germination but my reno had widespread germination within a week. Many other KBG reno journals seemed to have similar experiences. Is that 2-3 weeks driven by:
- hotter August temps accelerate germination, and if I went seed down now I'd experience much longer germination period?
- Applying a general rule to protect the slowest germinating seeds to ensure all have adequate time, even if some germinate in a few days?

Or some combination of the above/something else entirely? Not questioning the advice at all, just trying to reconcile it to the timing I saw on my reno.

 

I always see 2-3 weeks suggested for KBG germination but my reno had widespread germination within a week. Many other KBG reno journals seemed to have similar experiences.

The time required for germination of Kentucky bluegrass varies according to conditions (temperature, moisture, etc.) as well as the specific variety of KBG. Close to ideal conditions for "quick" cultivars of KBG can result in widespread germination of just about all the seeds in 5-7 days.

Is that 2-3 weeks driven by:
- hotter August temps accelerate germination, and if I went seed down now I'd experience much longer germination period?
- Applying a general rule to protect the slowest germinating seeds to ensure all have adequate time, even if some germinate in a few days?

Or some combination of the above/something else entirely? Not questioning the advice at all, just trying to reconcile it to the timing I saw on my reno.

As you surmised, the 2-3 week guideline is to cover the slower cases. Even if 5-7 days is the "ideal scenario" there are usually areas that are not quite as moist as they should be, or were slightly underwatered, or maybe dried out a little too much one day, or that are staying too wet, or are cooler due to more shade, or that got a little too soggy for a day due to natural rainfall, etc., which can make a section take a little longer. The seed could also be a variety of KBG that is slower to germinate. My understanding is that the 2-3 week guideline, as you surmise, is to cover those cases, too. Having a person decide that since they have a sparse area after 8 days that they need to put more seed down in that area might end up with an overcrowding situation, which would be less than optimal.

 

Awesome info, thanks @ken-n-nancy

 

Faster germination aside, just to hold dirt in place and it outcompeting KBG in this respect, I recall a article of a few than when Rye was seeded with KBG, there was -?- a chemical that Rye gave off that did not allow KBG to prosper and in subsequent years, the turf was manly all Rye with lil none KBG, even when KBG was seeded more heavily than the rye. I'm sure someone more seasoned might know the article I speak about

 

Faster germination aside, just to hold dirt in place and it outcompeting KBG in this respect, I recall a article of a few than when Rye was seeded with KBG, there was -?- a chemical that Rye gave off that did not allow KBG to prosper and in subsequent years, the turf was manly all Rye with lil none KBG, even when KBG was seeded more heavily than the rye. I'm sure someone more seasoned might know the article I speak about

The following article is an easy-to-read one, "Conversion of Ryegrass Fairways to Bluegrass: Impossible Dream?" which may be a summary of the journal article you remember. There have been other similar articles that I've seen as well.

In any case, I think it is generally accepted that overseeding KBG into a stand of ryegrass is a futile endeavor for everybody except the seed manufacturer...

Of course, that's a slightly different situation than seeding both together. Other articles indicate that ratios of over 80% KBG in a KBG/PRG mixture can result in mixed stands, even KBG-dominant ones, after 3 years in northern climates which give significant PRG winterkill.

 

From Zac Reicher

https://turf.purdue.edu/how-much-perennial-ryegrass-kentucky-bluegrass-in-a-mix-3/

 

@g-man good article. I found the invasion of poa A somewhat alarming, even though they say probably not typical. But 20%?! Sure hope I don't yield those results planting 100% KBG.

 

That's was before tenacity. There are more studies from UNL using round up, tenacity and other products.

 

Realize this is a bit OT but seems like OP has his answer so this seemed like a good opportunity to ask.

I always see 2-3 weeks suggested for KBG germination but my reno had widespread germination within a week. Many other KBG reno journals seemed to have similar experiences. Is that 2-3 weeks driven by:
- hotter August temps accelerate germination, and if I went seed down now I'd experience much longer germination period?
- Applying a general rule to protect the slowest germinating seeds to ensure all have adequate time, even if some germinate in a few days?

Or some combination of the above/something else entirely? Not questioning the advice at all, just trying to reconcile it to the timing I saw on my reno.

The germination time can be very misleading based on appearances.

Did you put down a KBG mix? Many mixes of 3+ KBG cultivars I have seen include one cultivar that is a "fast germination" type. These will germinate in 10-14 days where as many other cultivars will be 21-28 days. If that is what you had, you may have had widespread germination of the "fast" cultivar but you probably did not yet have widespread germination of the other slower types.

 

I just planted 100%KBG, and my results seemed like everything and all cultivars germinated at about the same time, and was about within 7 days of seed down. Given all cultivars were of "elite" variety including midnight/blue note/award, and an even mix. Every morning felt like Xmas in the first few days, but barer spots remained bare, and still are at about 23 days after seed down. Could one cultivar still pop up? Sure I suppose. But given the coverage I've got, I'd be shocked if anything that is going to emerge will start now.