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Just call me slim shady (Poa Supina experiment)

26K views 32 replies 14 participants last post by  Chinzw  
#1 ·
Hello!

I have a very shady backyard, that abuts the woods. Spring 2021 I seeded with a 25% Poa Supina mix (that I mixed myself) trying to grow grass in this very shaded area.

We bought the house 18 months ago, and since then trying to grow grass has been a legit comedy of errors.

I just want to give a little perspective as to what we started with.

This house is roughly 200 years old, we live in New England. The yard has been neglected a very very long time.

We started with a lawn of 75% crabgrass and weeds.





In addition to that there was ALL kinds of stuff buried...

Rocks...



Bricks...







Ridiculous amounts of buried tree roots..







A *PIANO HARP*!!







So we spent fall 2019 pulling weeds, then put down Scott's sun and shade. And because I have no idea what I'm doing, we didn't water it anywhere near enough. It didn't grow/died.

Then spring 2020, the Pandemic hit... so I took out my anxiety in the yard. This is when we started finding all the weird buried crap. I also planted approximately 37 gardens, beat back a bunch of invasives, and dug out a giant hedge infested with bittersweet. We wanted to try grass again, and we accidentally bought ANNUAL ryegrass seed, (again.... wicked inexperienced). I had no idea ANNUAL grass seed was a thing. So, expectedly.... it died.

Summer 2020, we did sun and shade again. But again not enough water, because I didn't know seeding in summer was dumb... and then we had.... "The Crabgrass Explosion of 2020". I briefly got SO excited that grass was GROWING..... then realized it was almost ALL crab grass, and plantain.



Fall 2020...... we tried again.... but were taken out by the leaves, we have a ton of Norway maples, and catalpa trees that have ENORMOUS leaves, and the rest of the trees are sugar maple.. I know in this picture it looks so pretty, quintessential New England. But this was basically less then an hour after leaf blowing the whole yard. The leaves just buried the brand new grass.



This brings us to.... Spring 2020 (in replies). If you've stuck with me this far, thank you!
 
#3 ·
Here is information about Poa Supina I've gathered.

Some of the information might be common knowledge to most of you, however it was not common knowledge to me... so I wanted to post it in the interest of leaving breadcrumbs behind.

Here is where I purchased the seed:

https://www.outsidepride.com/seed/grass-seed/shade-grass-seed/poa-supina-shade-grass.html

Someone local to me said that he also found it locally at Valley Green. Here is his post in a New England lawn FB group with his experience seeding a Supina patch in his yard:
https://m.facebook.com/groups/237206566959289/permalink/304380673575211/

One of the biggest draws to me is that Poa Supina spreads aggressively, with stolons (sideways above ground rooting systems), and thrives on traffic. The more traffic and abuse it gets, the more it spreads. It can be seeded at a rate of 5-10% supina in a mixture, and the supina will dominate the other grasses within 3-5 years.

Also due to this aggressive growth, it accumulates thatch quickly.

It has more shade tolerance then any other grass type, Especially in high traffic areas. It can tolerate 90% shade.

It can be mowed super short. Less then an inch, and typically prefers lower mowing heights. However it will do better in shade with higher mowing heights, at least 2 inches (so that the grass blades have more surface area in which to absorb sun, and photosynthesize).

It has poor drought tolerance, and heat tolerance, due to it's shallow roots. It needs more water the other grasses (ideally needs 1-1.5 inches of water per week.)

It has a Nitrogen requirement of 4-6lbs per 1,000 square feet, per year. I am finding conflicting information about this, and I'm unsure how much the shade will affect how much Nitrogen it should get.

It has a bright lime green color, that I'm reading can be temporarily darkened with iron. A few of the research articles did say that they expect future cultivars to be bred with darker colors, however it doesn't seem there's much urgency on that, because it's most popular in Europe where they prefer the lighter colored grass. The light color doesn't bother me at all, but I know that darker grass is generally preferred and viewed as more attractive here. I may experiment with iron to see what it does, for science..... if I can get it to grow and live 🤪

The cultivar most commonly available in the US is supranova. All cultivars are really expensive, because it's not being produced by many places, and where it is being produced, I guess the plants don't make very many seeds. For this reason, it's actually currently not being sold as a pure seed in Germany, only within mixtures.

Here are some research articles I have found:

http://gateway.selltec.com/go/eurogreen/_ws/mediabase/EG/PDF/Poa%20Supina/Lundell_1994_GM_26-27.pdf

https://cdn.shopify.com/s/files/1/0145/8808/4272/files/A3759.pdf

https://archive.lib.msu.edu/tic/mitgc/article/1998184.pdf

https://archive.lib.msu.edu/tic/stnew/article/2001mar12.pdf

https://line.17qq.com/articles/doeihgbdz.html

Here are some social media accounts and groups:

Perfect Green (Felix Traub)

https://www.facebook.com/FelixPerfectGreen/

https://youtube.com/c/PerfectGreen

He has a FB page and a YouTube channel and has a lot of videos about Poa Supina care. His channel is in German, however YouTube will auto translate on IPad and laptop, (I couldn't figure out how on mobile). Turn on closed captioning, and then you can change the language settings. The translation is imperfect, which did result in some information being a bit confusing, however Felix, and other people in the German lawn groups below were more then happy to clarify when I asked.

Here are a few German lawncare Facebook groups. Poa Supina is relatively common there, especially in shade lawns, so they were incredibly informative. They also were SO patient with my use of Google Translate to communicate with them.

https://www.facebook.com/groups/298366680973085/?ref=share

https://www.facebook.com/groups/1292465140947188/?ref=share

This Instagram also grows Poa Supina and has some information, in German. However Instagram as a platform is really unfriendly to translating, you can automatically translate the original post, but not the comments. This is annoying. This user however, like the rest of the Germans was really helpful when I reached out in PM. His videos and photos of supina's aggressive repair are pretty incredible.

https://instagram.com/privatelawncare?igshid=empf2pnfdc6x
 
#15 ·
The Lawn Monk said:
Had to laugh about all the buried treasure ya found. I feel your pain! Ripped up mine last fall and besides the bricks, rocks, and plumbing pipes, there was sooo much glass. Like, thin picture frame glass. Everywhere. I wonder if it's just a Northeast thing? Yours is coming in great!
Omg I didn't even mention the glass! Sooooo much! Before we lived here, the house was rented to younger people. So our glass is mostly bottles. And I suspect theirs.
 
#16 ·
Here's a photo of my Poa Supina experiment
This photo is of Poa S plugs I planted last October. Its along a shady road. The red square outlines the Poa S.
The other grass is a mix of fine fescue, tall fescue, and some scraggly bluegrass. There is a distinct color difference but its not intolerable. I've never been able to get a dense turf in this spot and the Poa S is doing an admiral job at it.

If you consider that the Poa S is planted over a gravel road bed with only about a half inch of dirt over it, I think its doing pretty good. Its survived a winter and is holding its own in this no-rain summer.

 
#17 ·
I have a part of my back yard with glass bottles buried in it, too. The original owners of the house were Eastern Europeans and apparently thought that was fine, from about 1965-75???? I don't get it. It's also under a couple of feet of sand, and I don't think the sand is local. It's all very confusing.

Beware of traffic when the supina is wet. It has shallow/fragile roots that sheer really easily, and then it dies. It takes traffic on dry ground like a champ. This is a cause of its failure on sports fields! You cannot, cannot use it wet!

Right now, I'm watering it to a minimum of an inch a week using Scott's lawn app to track how much rain in the last 7 days. It's so easy. I am not sure if this will be sufficient over the summer, but I also don't want it to stay too wet.

So people have helped me out with supina resources. Supina goes necrotic rather than dormant. This is a worry for it.

University of Michigan found that it held up to traffic best at 1-1.5" in height. However, it resisted summer necrosis best the shorter it was, so I'm going 1" and staying there.

This dude has a successful poa supina lawn. You can get automatic translation into English--it only messes up the words fescue and poa supina, lol: https://www.youtube.com/watch?v=mz3FOy-3Gr0

This guy tried a poa supina lawn and failed. It went too necrotic over the summer. https://aroundtheyard.com/forums2/viewtopic.php?f=4&t=7082 But notice that he raised the mow height to 2".

My poa supina has been there for nearly 4 years now, mostly badly neglected. So I'm hoping it'll pretty up and spread more aggressively now that I'm caring for it.

The boys here tend to looooove their dark green. ;) I just have an abiding hatred of fine fescue. It's a horrible grass for me. So I don't care about the shade. I just want a nice lawn-like lawn. We can be the supina girls if it works out for us.
 
#18 ·
****o1 said:
Here's a photo of my Poa Supina experiment
This photo is of Poa S plugs I planted last October. Its along a shady road. The red square outlines the Poa S.
The other grass is a mix of fine fescue, tall fescue, and some scraggly bluegrass. There is a distinct color difference but its not intolerable. I've never been able to get a dense turf in this spot and the Poa S is doing an admiral job at it.

If you consider that the Poa S is planted over a gravel road bed with only about a half inch of dirt over it, I think its doing pretty good. Its survived a winter and is holding its own in this no-rain summer.

Right?! This stuff is *magic*! I'm in love.

And I agree the color isn't bothersome at all, to me..
 
#19 ·
Lawndress said:
I have a part of my back yard with glass bottles buried in it, too. The original owners of the house were Eastern Europeans and apparently thought that was fine, from about 1965-75???? I don't get it. It's also under a couple of feet of sand, and I don't think the sand is local. It's all very confusing.

Beware of traffic when the supina is wet. It has shallow/fragile roots that sheer really easily, and then it dies. It takes traffic on dry ground like a champ. This is a cause of its failure on sports fields! You cannot, cannot use it wet!

Right now, I'm watering it to a minimum of an inch a week using Scott's lawn app to track how much rain in the last 7 days. It's so easy. I am not sure if this will be sufficient over the summer, but I also don't want it to stay too wet.

So people have helped me out with supina resources. Supina goes necrotic rather than dormant. This is a worry for it.

University of Michigan found that it held up to traffic best at 1-1.5" in height. However, it resisted summer necrosis best the shorter it was, so I'm going 1" and staying there.

This dude has a successful poa supina lawn. You can get automatic translation into English--it only messes up the words fescue and poa supina, lol:

This guy tried a poa supina lawn and failed. It went too necrotic over the summer. https://aroundtheyard.com/forums2/viewtopic.php?f=4&t=7082 But notice that he raised the mow height to 2".

My poa supina has been there for nearly 4 years now, mostly badly neglected. So I'm hoping it'll pretty up and spread more aggressively now that I'm caring for it.

The boys here tend to looooove their dark green. ;) I just have an abiding hatred of fine fescue. It's a horrible grass for me. So I don't care about the shade. I just want a nice lawn-like lawn. We can be the supina girls if it works out for us.
I have noticed that Supina really does play by ITS rules... which are contrary to most cool season grass rules. Mow short. Fertilize like CRAZY.

I do watch perfect green, his videos were super helpful. There's a couple instagrammers with successful supina lawns too.. @privatelawncare and @weekendwarriorlawn.

My yard is SO shady it's pretty ... juicy. Most of the time 😂😂

It does ok with that, with little kids. But I also have banned wheeled toys on it (they love dragging wagons around. Noooope 😂). But it did great with 6 year old sprinkler play!



I think if it were harder use, like cleats... or dragging something, that would be problematic.
 
#21 ·
I need to update from the last two weeks!

May 28th I mowed for the first time. With a reel mower. Really really gently.

Baaawwwww baby's first stripes! (this is the over seeded back of the back yard)
https://www.dropbox.com/s/8fcuj1rlcwf8gip/Photo%20May%2028%2C%201%2035%2028%20PM.jpg

PS- I mow like I'm drunk 😂

I also could begin to see the color difference between Supina and "normal grass".

Supina vs Scott's color https://www.dropbox.com/s/ijo9ce5l1xm30yw/Photo%20May%2028%2C%201%2056%2039%20PM.jpg

Memorial Day weekend (5/29-5/31) we got INUNDATED with rain. 3.5 inches over 3 days. Insane.

Before the rain vs after. 5/27 - 6/1

https://www.dropbox.com/s/rvred7wb7cupf0y/Photo%20Jun%2001%2C%207%2027%2058%20AM.jpg

The first week in June I noticed a HUGE slow down in the spread and growth. I fertilized on May 23... and then we got all the rain. Supina is hungry to begin with, and I have trees competing..... and I think the huge amount of rain pushed all the nitrogen out of the root zone. Supina has stubby little roots. ~2 inches or so.

5/22 - 5/27 - 6/4 comparison. Supina slowed WAY down.
https://www.dropbox.com/s/2e7145avt4ae78i/Photo%20Jun%2004%2C%204%2040%2046%20PM.jpg

Also on June 4th, I noticed signs of disease. The lawn really did not appreciate 3.5 inches of rain in one go, followed by a 90+ degrees heat wave😂.

Disease. https://www.dropbox.com/s/8azzs8qdc6corhg/Photo%20Jun%2003%2C%203%2029%2048%20PM.jpg

So I hemmed and hawed on whether to apply more fert. Americans were saying no, definitely do not do. Excess N in summertime promotes disease. Germans were saying Supina has a huge N requirement. Do the fert. In the end I went with German recommendations and applied more.

6/5 - fertilizer, BioAdvanced fungus control (at curative rate), and liquid Hume went down.

I got a harbor freight 4 gallon pump backpack. Do. Not. Recommend. 😂. It was so annoying and frustrating. But I got the Hume down.

ONE day later on 6/6.... fertilizer was the right move. DANG.

6/4 - 6/6 comparison. fertilizer on 6/5. https://www.dropbox.com/s/lm93spu1joa3jak/Photo%20Jun%2006%2C%2010%2026%2014%20AM.jpg

Also on 6/5 I started reducing the height of cut. Mowed at 2 inches. And started mowing daily. I also removed the Kid Highway, and set the kids loose on the supina.

Mission: "abuse supina so it grows" has begun

6/6. lower cut. https://www.dropbox.com/s/kgk02mhp4qa5hs8/Photo%20Jun%2006%2C%208%2035%2002%20AM.jpg

6/4 - 6/8 comparison. Go go go!
https://www.dropbox.com/s/tuoqvmg2pk7l2l0/Photo%20Jun%2008%2C%207%2050%2042%20PM.jpg

On 6/10 my (6 year old) son expressed interest in lawn mowing... sure! I set him loose with the reel mower on the back half of the yard (the overseeded part).

Aside from him mowing more crooked then I do... (like a human roomba 😂😂). He did a good job!

Child Labor
https://www.dropbox.com/s/2n18cgo07x103vm/Photo%20Jun%2010%2C%205%2023%2016%20PM.jpg

Child Labor Video - it'll all get mowed..... eventually. LOL
https://www.dropbox.com/s/nxw9puq3ts83v8m/Video%20Jun%2010%2C%205%2024%2049%20PM.mov

6/13 - at the German recommendation; I reduced the height of cut again(on the left hand side primarily supina area). To 1 inch. Last week was 90+ degrees. This week the highest high is 82. I figured it was a good week to test this. I mow this area daily, so if it gets pissed off, I'll just skip mowing a couple of days and let it grow out.

1 inch!!!
https://www.dropbox.com/s/vw08y0zm1ei2d5n/Photo%20Jun%2013%2C%209%2045%2017%20AM.jpg

6/6 (2 inch cut) - 6/13 (1 inch cut) close up comparison.
https://www.dropbox.com/s/zn0iiulzmfguotn/Photo%20Jun%2013%2C%2010%2059%2059%20AM.jpg

Here are some videos of the left hand, mostly supina area. After the 1 inch cut. SO thick!!!!!

I am beyond amazed at this grass (video)
https://www.dropbox.com/s/km73rbgybbztqn7/Video%20Jun%2013%2C%209%2039%2056%20AM.mov

You can see some fescue. But it's a LOTTA supina. Thick!

Thick grass close up video https://www.dropbox.com/s/g2hvg9rokg342z7/Video%20Jun%2013%2C%209%2037%2043%20AM.mov
 
#23 ·
Great progress Alison! Love the 6/4 - 6/8 comparison. My supina has always looked its best in June.

So I hemmed and hawed on whether to apply more fert. Americans were saying no, definitely do not do. Excess N in summertime promotes disease. Germans were saying Supina has a huge N requirement. Do the fert. In the end I went with German recommendations and applied more.
Just my 2 UK cents but I think both are correct. Excess N in summer heat is baaaad. But you do want enough N and moisture kicking around to try to maintain a healthy growth, spoon feeding (low rates) based on your needs is probably best. When you hear that something has huge N requirements, which supina does, definitely don't drop a big chunk of the season requirements in summer! How much fert did you drop?

Also great that you did the soil test, what's your plans for getting any lime down? If you post the results on the soil fertility thread, you are sure to get some very useful feedback.
 
#24 ·
Mark B said:
Great progress Alison! Love the 6/4 - 6/8 comparison. My supina has always looked its best in June.

So I hemmed and hawed on whether to apply more fert. Americans were saying no, definitely do not do. Excess N in summertime promotes disease. Germans were saying Supina has a huge N requirement. Do the fert. In the end I went with German recommendations and applied more.
Just my 2 UK cents but I think both are correct. Excess N in summer heat is baaaad. But you do want enough N and moisture kicking around to try to maintain a healthy growth, spoon feeding (low rates) based on your needs is probably best. When you hear that something has huge N requirements, which supina does, definitely don't drop a big chunk of the season requirements in summer! How much fert did you drop?

Also great that you did the soil test, what's your plans for getting any lime down? If you post the results on the soil fertility thread, you are sure to get some very useful feedback.
I got some lime down REALLY early season, and I'm probably due for more.

I put .75#/1k down on 6/5 and 6/17 (with dimension this app, I'm finally 2 months from seeding and I by some miracle beat the race against crab grass!). I'm also competing with a bunch of trees 😬. However probably laying off until late July at this point, summer is short in Massachusetts, but it's basically the entire month of July 😂. And I do have irrigation.

I thus far have NOT put hydretain down, I have some but haven't needed it yet. I may put it down on the areas of the lawn that get "more" sun and possibly not on the shadiest areas.
 
#25 ·
If the 0.75 N had a good amount of polymer coated N in it, no worries. It's the initial fast release portion you'd want to mostly take into account and keep as low as possible. 0.5 lb or less should be ok (e.g. if the fert had 1/3 of its total N from polymer coated N). Usually, Dimension with Nitrogen does have some polymer coated urea in it. (Sulfur coated urea without polymer tends to dump everything in the first month or so as the prills get crushed and wet, so that wouldn't help much.)

Anyway, June is a fine time to fertilize generally in our climate as long as it's not dry. N uptake is very efficient due to warm soils. But it's going to be July in another week and a half and the soils will bake. ;) I personally don't fertilize with N in July. But I would definitely pick back up in mid to late August with another 0.5 lb or so.

If you want to fertilize with N in July, I'd keep it low (0.25 lb or less per app and give it a good two weeks to judge the response for synthetic) but maybe use organic. If the grass doesn't look like it needs it, I wouldn't do it in July. I feel like July N is something that should only be done if needed.

I haven't sprayed Hydretain yet, either. But I feel like it's a bit late and I'm antsy for the right conditions (rain) so I can do it. I use it on a mostly nonirrigated area.