Grass in Colorado (or just Kentucky Bluegrass in general)

If anyone knows about this stuff, any information would be greatly appreciated. This is my first summer in a new house. I fertilized the grass a few weeks ago. The 2 pics are from early May and today. I have these dark green spots that seem to be evening out (or taking over, I’m not sure which). I am concerned that it’s crabgrass or poa annua, neither of which would be good. It may also just be good grass. I have no idea. It’s definitely different than the “normal” grass. Anyone know what’s going on? Should I just let it be and take care of it normally?

Early May:


Today:

 

I often have the same issue on my grass. I have balanced the ph, fertilized it, aerated it, and made sure the sprinklers are giving even water. The only thing I have left to consider is the quality of the soil under the grass is just a little better that other areas. Here’s mike for reference, don’t mind the kiddo.

 

Yours looks a lot more even than mine, it looks awesome actually. Do you know what month you took that picture? Mine seems to be improving as the weather warms up.

 

The pic was taken a couple weeks ago. Mine is also improving with weather but I still have some spots that are a fuller green than others. Like you, I’m in the high desert in Prescott AZ. It’s hard here since grass doesn’t grow naturally for us.

One thing that I have considered doing is over-seeding with a warm season grass then top dressing about 1/2” with some new healthy soil. I may eventually do that but I’ll give the grass some time first.

Edit: another thing I’ve recently started doing is mulching the grass instead of bagging it. This allows for the nitrogen rich mulched grass to fertilize the grass and also allows the layer of thatch to get nutrients as well.

 

Thanks. My parents live in Chino Valley so I know that area. I’ll keep that idea in mind. Since it’s new, I’ll probably just fertilize, water, and mow often this summer and see how it goes. I didn’t aerate but may try that next year. If it doesn’t end up looking good, I’ll look into those ideas. It may be ok but looks pretty bad so far, and it’s almost June.

 

Since it’s new then you definitely don’t need to aerate. I had sod put in last year and only aerated because the dirt the sod was put on wasn’t the best dirt. The areas that the grass is full and green had fresh soil (to add a little slope for drainage) added before the sod was put in.

What are you doing for a watering schedule?

 

I am watering Monday, Wednesday, Friday. The sprinkler system has 7 zones, and I’m running it for 15 minutes per zone. It starts at 6 AM. I am definitely open to suggestions on that, I kind of just made that schedule up as a starting point. The lot is about 1/4 acre if that matters.

 

I have mine going daily at 5:30 for 10 minutes. I seem to be getting decent results this way. I did try a deep watering once a week but I got mushrooms in my yard when I did that so I don’t water for more than 10 minutes anymore.

Your grass alone has 7 zones? My back yard grass area is only about 1500 sq/ft so it’s 2 zones.

If you have 7 zones of grass then I would suggest starting a little sooner. From what I’ve understood, watering with the morning sun on it is hard on the grass and some of the water is evaporated by the sun. Watering earlier allows the water to soak into the soil before evaporation happens. I’m no expert here but that’s just what I’ve been able to find online.

 

It has 7 zones, but there appears to be a lot of overlap. It could probably be done with 5. I am going to change it to start at 5 AM. I had it at 6 so that the grass would be dry when I took the dog out but that’s not the best way to plan this. Thanks, I appreciate it!

 

You’re welcome. One thing you may want to do is add a little bit of seed then a little mulch over the seed in the areas where the grass is thin. I had some areas in between the sod strips that needed some help.

 

I set the sprinklers to start at 5 tomorrow. I’ll give it a little longer and then consider seeding. It is growing fast so I am hoping it fills in quickly.

 

Ill break this up so it's not just some super wall of text.

I skimmed this post, you mentioned dog? Those look like urine/poo spots. Urine does strange things to grass depending on what your feeding your dog and urine can bleach or behave like a shot of fert. Poa Annua is a thin whispy blade that sends up thin "straw" like stalks when it matures with tiny white/yellow flower buds in my neck of the woods. From this distance, it doesn't look like Poa Annua. Crab grass will run thicker blades of grass that look like tiny spear tips. They are a rizome/stolon grower which is similar to Kentucky blue. You'll want to confirm whether or not Colorado has any fert restrictions before starting a fertilizer program. This seems like a lot of information but check out this Colorado State University article listing. I find it easier to get information from those around you. Also, if you're over-seeding, there's two seeding windows: spring and fall. Most DIY over-seed in the fall since it's a 'set it and forget it' to green up in the spring but it is possible to over-seed in the spring when soil temps reach average 55 degrees but you may be fighting weed germination at the same time. You can check your average soil temps with an electric thermometer. Just jab that into the dirt about 4 to 6 inches below the soil line to get a reading if the misses allows, or you can be lazy and check out this fantastic tool from greencast that allows you to pick a place and date to build your yard schedule out by checking out average temperatures/forecasts.

Pre-emergent weed control prior to winter dormancy (temperature dependent) which should control early weeds in the spring. This'll take a bit of research on your end to find out what weeds are prevalent in your neck of the woods which sets what chemicals you pump into your yard. Most of the big box stores carry your typical Round-up, Weed-b-Gon, etc.. but if you want to pro it up, you'll need to get your weed control items from domyown or Amazon, or wherever. In the spring, you can control weeds with an application of post-emergent weed control. Liquid application rates are typically faster acting but granular products usually treat for a longer time in my neck of the woods. You'll want to measure the square footage of your yard to adjust rates as according. There's a difference in "bag-rate vs App rate". Bag rate is typically in a "2500 sq ft to 5000 sq ft", and app rate is typically in lbs per 1000 sq ft. I can't find a good pic of a bag of fert, but it's usually listed on the front of the bag for bag rate, but if you look on the back you'll see app rate in per 1k sqft. I base all my calculations off of App rate. Get yourself on of those small paint buckets from the hardware store and a scale to measure out your granulates. Liquids are similar but you need to see how much product comes out of your applicator before spraying on your yard. You can do the bucket challenge by taking a 5g bucket and timing how long it takes to spray 5 gal into the bucket and measuring how much water is left in the mixing canister. Now you'll know how long it takes for you to spray out 5 gal of product and how much product your getting out. It sounds complicated, but "The Lawn Care Nut" has a lot of videos on this subject. I keep it easy with granular products.

Snow mold. Coming out of winter, you might see snow mold spots if you have sitting snow on your yard for long periods. These typically will heal on their own but in my neck of the woods, we don't see much snow so you'll have to look this up on your own.

Water is important, Kentucky blue needs 2" per week, but you should still measure out your sprinklers watering rate. Don't just trust what the previous owner had set. Get a rain gauge so you don't over water and if that picture is your only grass patch, I would take a few Dixie or Solo cups and cut the tops off so they are smaller - think petri-dish. They'll need to be at least 3 inches in height. Scatter about 4 of them around your yard before your sprinklers go off and measure how deep the water is after they complete their run cycle. If your watering twice a week, you'll be looking for about 1" per cycle for 2" per week. Colorado weather forecast might push rain in your watering schedule so adjust as needed. One of those fancy rain-bird units that connects to wifi would help to turn off sprinklers if rain is in your forecast +-3 days. Deeper watering is better than short watering, if that makes sense. Basically, longer watering periods are better than many shorter watering frequencies - think: that water needs to reach the bottom of the root.

Set your mow height to around 3.5-4" and try to mow at least twice a week during the active growing period, especially after you burst fert all over your yard. Don't cut off more than 1/3 of the grass blade, you could stress your yard which turns it brown. It will recover when watered and treated with respect. You can remedy a lot of yard problems just by mowing. Weeds can't keep up with active mowing and expel all their energy attempting to grow out which results in them dying when treated with a post emergent weed app. Grass is a hearty plant and will recover most everything you do to it. For the dog spots, you might want to think about training your dog to do its business in a certain area of the yard or you can get a patch of astro-turf and train the dog to go there if you're combating yard spots. If that's not a possibility, try different food brands. This method is the long game since results aren't instant.

The Bag vrs Mulch debate: I'm in the mulch wheelhouse. My reasoning behind this is, you're spending money fertilizing your lawn which in turn, gets absorbed into the blades of grass. When you mow, your chopping those little bastards down to tiny bits that break down and get reabsorbed into the lawn. If you're bagging, you're removing the fert that was absorbed and taking it off-site. Basically, it's up to you.

Lastly, if you want to go crazy, you can get a soil test done. I haven't done this personally so I can't recommend a specific kit but it's nice to know what your yard is lacking or has too much of so that you can adjust your soil amendments as necessary. Not all Fert's are the same, but they all follow the N-P-K ratio of Nitrogen - Phosphorous - Potassium (yeah, science). Think of it this way, Nitrogen drives the bus: meaning nitrogen is going to push growth in both roots and plant, nitrogen moves through the plant faster than the other chemicals so the effects aren't long lasting from high nitrogen hits. Phosphorous helps the plant store energy in the roots for healthy roots, and potassium helps the plant resist disease among other things. These are commonly referred to as Macro-nutrients, or the building blocks of a healthy yard strata. Micro-nutrients are more like targeted hits such as Iron or Lyme, you'd find out what your yard is lacking if you ran one of those soil tests. If you want a quick pop of luscious green, put down a liquid application of Iron 2 to 3 days prior to your event and you'll have the greenest yard on the block. Be mindful that liquid or granular iron will stain concrete so don't get any on your patio or driveway. You'll be crying all the way to winter. Iron burns out quick so expect to have a green iron punch for about 5 days total before it grows back down to normal color. Now you can choose between Organic fert (milorganite is what I run, you can thank the nice people in Milwaukee WI for providing their poo), or Synthetic fert. If you're new at putting fert down, I would suggest starting with an Organic fert since you cant really mess that one up by doing a heavier application. If you go heavy with a synthetic fert you have a higher chance of burning your lawn or putting unwanted yellow stripes. There's also a hybrid type of both organic and synthetic but those are specialty and I don't think you can get them at the big box stores, at least I haven't been looking. Practice with the organic fert and once you get comfortable putting those down, then you can move to the synthetic ferts as they have to be measured out and put out evenly or you'll be asking for trouble.

I'm no expert on your grass type but there are some excellent yard peoples on the YouTubes, namely 'The Lawn Care Nut' who had a Kentucky blue before he moved to a southern climate so you'll have to search his earlier videos. 'Jake the Lawn Kid' has a Kentucky blue yard. 'Ryan Knorr' reel mows low and has a northern family of grass, I can't remember which at the moment. Lastly, 'Conner Ward' who also mow's low and lives in a northern climate. These channels is where I have gleaned all my yard knowledge over the years of home-ownership. I know this has been long winded but I hope it helps you out.

-J

 

Thank you for that, I really appreciate it. I will definitely be coming back to this post. I read it all now, but will need to reread it as I am doing things.

I think the dog pee theory is probably right, with the nitrogen causing the green spots. The front yard has a lot less of those spots, but does have some because he pees out there occasionally.

I mow twice a week for the reason you stated. I also used an organic fertilizer for the reason you stated. I have thought about doing the measuring thing with the cups, just need to actually do it. It is a new build, so I didn’t have a previous owner to get a baseline yard care routine from.

Again, thanks, this post will be looked back at many times as I tweak my routine!

 

@JustAddMud

What a post! Thanks for all the info. I’ve been going full retard on my yard so your post is super helpful for me as well.

as for the ph balance of the yard, if you want the good grass I haVe heard that’s important. I use a little $20 probe from Home Depot and it works well. Take a small cup of soil from the yard and get it muddy with distilled water. It’s important to use distilled water since tap water has a bunch of stuff that will throw off the test. Make sure the probes are clean and stick the meter in the cup of muddy soil for about 10 minutes. The meter will tell you what your soil is rich in.

 

If I was to give you the short and dirty (you'll have to adjust depending on weather/soil temps):

1. When soil temps are starting to hit 45-50 degrees daily average, get out the wide bladed wire rake and rake your blades of grass so they stand back up if they were impacted by snow mold and put down an application of pre-emergent weed control.

2. Soil temps hitting average daily of 55 degrees. Over-seed now if you want or wait until the fall when temps dip again. First application of fert and you can start your watering regimen at this time.

2.a. Spot treat weeds with a post emergent as they come up or you can blanket treat after about 2 months post 'pre-emergent' application. The active ingredients should be different, otherwise you may damage your turf.

3. 3 months after first application of fert, you can do a second application of fert. This should take you to winter dormancy.

4. 3 to 4 weeks prior to soil temps hitting 55 degrees again before winter, apply a fungicide which will help prevent snow mold in the winter. Fungicide should be rotated every other season, meaning don't use the same active ingredient to prevent the fungus from building an resistance to it. There are 3 main types but I cant remember off the top of my head so as long as you rotate the active ingredient, you'll be good to go.

4.a. If you want to over-seed, this would be the time to over-seed to prepare for next year. Also at this point, you would de-thatch (mechanically or chemically: I prefer mechanical de-thatch) then core aerate (rent the machine, your back will love you), then over-seed followed by a top dressing that you rake into your soil to help fill in the holes you made from the core aerator. I'd leave the cores on the yard, let them break down back into the soil but if you want to reel mow, you'll want to rake them bad boys up.

4.b. Winterize your lawn by feeding it a half(subjective; some say 1/3) rate of fert. If you're feeling ballzy, this would be when you'd run the synthetic fert since you need a fast acting fert to kick root growth into high gear the last 4 weeks before the ground starts to shut down. This step isn't required but it will help your yard wake up in the spring.

5. Keep mowing until the grass starts to turn a tinge of brown, you might want to take your grass down another 1/2" than normal at this point. Meaning, if you're mowing at 4", mow this one at 3.5", .. etc.

-J

 

I will have to look into this. For $20, there's no reason not to give it a try and see what it says.

Thanks again. We moved into this house in late December of last year, so I didn't have a chance to do any of the prep work. I basically just waited for it to start growing this year, raked it well, fertilized it, and began mowing (always mulching). When comparing it to the other new houses on my street, it is one of the best looking lawns. I need to look into what to do this year though to prepare it for the next winter.

 

Thats a good starting point however, not all grass thrives in the same PH. Centipede grass that I have likes higher almost acidic soil whereas the northern varieties like lower PH. Don't get me wrong, that is better than not doing a test but doing a soil test where you list your grass type when you mail it off will give you tailored results specifically for your grass. I really should take my own advise and get one done. Just a note on soil tests, take a few across the yard, like one where you're getting full sun and one under a tree or shade as they might be different.

-J

 

Lawn care is a labor of love, I'm still playing catch up on my yard and I've lived here 3 years now. The previous owner didn't take care of the lawn and it was 50/50 weeds/grass. It takes time, don't expect a quick turnaround, especially with animals in the yard. Just keep up the routine and you'll see drastic improvements over the course of the years. I'm over-seeding with centipede which takes 12-18 weeks to germinate, thats watering lightly 3x a day until germination then I can cut back to 1-1.5" a week. I'm starting to loath Centipede but it's supposed to be a low mx lawn once established. Ugh.

-J

 

Here is a little reference. I just took this picture out the window, which shows my side yard and the neighbor’s back yard. I don’t think he has done anything yet (not even mowed), so I can see that I’ve done some good. You can also see the common area in the background, but that’s older grass so it has had more time to establish itself (a few years I think).

 

Just saw this, sorry I skimmed quickly and missed this post originally. I would try to push watering to just 2 days a week, heavy 1" per zone. ~ 1/4 acre isn't that large and seems to be an average yard size for the Burbs. I would set your watering schedule to run Monday and Thursday. Early morning waterings are better because it allows the grass to soak it up and dry through-out the day. If you water at night, the grass stays wetter longer and this can introduce molds and fungus. If you're treating for this, then it shouldn't matter but if you're starting to see a lot of mushrooms growing, I would see if you can tweak your watering to occur for times that will allow for your yard to dry out before shutting down for the night.

-J