# Help with analyzing Soil Test results, for Bermuda sod install



## LushLife18 (May 10, 2021)

Short version: I'm installing Bermuda sod (Tahoma 31) in a couple weeks, and just got the Soil Test results back from Virginia Tech. My layman's quick take is that it looks like I need to focus a little on K and especially P, and maybe increase pH a smidge. But what do the more seasoned guys (especially those that know Bermuda) think… how should I amend the soil?



Also, a little background on my renovation: the area is about 10K sqft, and has the unique "feature" of having two large HDPE culverts/pipes running under the yard diagonally, routing a creek underneath our property. The pipes are only about 6 feet wide, but the water doesn't drain well above them. There are about 12" of soil above the pipes. We hired a drainage contractor who will be adding 20-28 cu yds of soil and re-grading the entire area to raise the level 2-3" as needed. Some of the dirt will actually be harvested from my hillside behind the area being renovated. After the re-grade, they will install a layer of McGill Compost and then the sod. Then, looking ahead a bit, I am planning to inter-seed the Bermuda with KBG in the late summer/early fall to try to establish a Bluemuda stand over time. I plan to do the soil amendments after the re-grading but prior to sod installation. Are there any other amendments or changes I should make to the soil profile, before the sod? For example, is my soil depth of ~12-14" in the area above the culvert sufficient for Bermuda rooting, or do I need to add more? Here's a pic of the area:


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## Virginiagal (Apr 24, 2017)

The Va Tech report assumes you will be tilling for a new establishment. If you were, you could apply the whole amount of lime and the first fertilizer application and the compost and mix it all together. But tilling brings up weed seeds and can make the yard bumpy. You have an experienced contractor doing the work, don't you? Use his judgment. You want a smooth even surface to put the sod on. If you don't till, spread 50 lb per 1000 sq ft of lime. You can do another 50 lb per 1000 sq ft in the fall. A starter fertilizer will give you the phosphorus. Thereafter look for a fertilizer with about equal amounts of nitrogen and potassium. Bermuda is fertilized throughout the summer.


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## Virginiagal (Apr 24, 2017)

Sorry, misread the report. They aren't recommending extra K except for the first application. Just nitrogen will do.


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## Virginiagal (Apr 24, 2017)

Giggling says Bermuda roots can go to six feet but most are in the top six inches.


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## LushLife18 (May 10, 2021)

Virginiagal said:


> The Va Tech report assumes you will be tilling for a new establishment. If you were, you could apply the whole amount of lime and the first fertilizer application and the compost and mix it all together. But tilling brings up weed seeds and can make the yard bumpy. You have an experienced contractor doing the work, don't you? Use his judgment. You want a smooth even surface to put the sod on. If you don't till, spread 50 lb per 1000 sq ft of lime. You can do another 50 lb per 1000 sq ft in the fall. A starter fertilizer will give you the phosphorus. Thereafter look for a fertilizer with about equal amounts of nitrogen and potassium. Bermuda is fertilized throughout the summer.


thanks @Virginiagal! It's a 10K sqft area, so that'd be 500lbs of lime  Yep the contractor is very experienced. I do not believe he plans to till. So it sounds like the best plan is to spread the lime on the bare dirt just prior to laying sod.

Looking at Lime products, I see a few options.
1. Soil Doctor Pelletized Lawn Lime, 40lbs for $5. https://www.lowes.com/pd/Soil-Doctor-Pelletized-Lawn-Lime-40-lb-Organic-Lime-PH-Balancer/3062133

2. Greenlawn Ultrafast, 50lbs for $24. Much more expensive. Do I need this superfast acting one, or can I go with the cheaper option above?
https://www.southernstates.com/catalog/product/p-19017-greenlawn-ultrafast-lime-50-lb


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## Virginiagal (Apr 24, 2017)

Go for the less expensive regular lime. You can do 50 lb per 1000 sq ft with that one, With the fast acting one you are much more limited in how much you can apply at a time, so you would be making smaller applications over a longer period. I can't see the back of the bag to read the instructions, but if 50 lb covers 10,000 sq ft as the front says, that's only 5 lb per 1000 sq ft. It would take years to put down the 120 lb. per 1000 sq ft in twice yearly applications at that rate. The fast acting limes do react quicker and raise pH faster but the effect is short lived because you can put down only so much at a time. The instructions probably give other rates, maybe 10 lb per 1000 sq ft or a little higher, but it's not going to be anywhere near 50. The slower acting limes will react gradually over the next few years. Your pH at 6.1 is acceptable as is. They are making the recommendation to get you to the target pH of 6.5, Your soil is apparently somewhat heavily buffered, meaning it takes more product to make a change than on a lightly buffered soil.


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## LushLife18 (May 10, 2021)

Virginiagal said:


> Go for the less expensive regular lime. You can do 50 lb per 1000 sq ft with that one, With the fast acting one you are much more limited in how much you can apply at a time, so you would be making smaller applications over a longer period. I can't see the back of the bag to read the instructions, but if 50 lb covers 10,000 sq ft as the front says, that's only 5 lb per 1000 sq ft. It would take years to put down the 120 lb. per 1000 sq ft in twice yearly applications at that rate. The fast acting limes do react quicker and raise pH faster but the effect is short lived because you can put down only so much at a time. The instructions probably give other rates, maybe 10 lb per 1000 sq ft or a little higher, but it's not going to be anywhere near 50. The slower acting limes will react gradually over the next few years. Your pH at 6.1 is acceptable as is. They are making the recommendation to get you to the target pH of 6.5, Your soil is apparently somewhat heavily buffered, meaning it takes more product to make a change than on a lightly buffered soil.


@Virginiagal Excellent advice; thank you! I will go with the regular lime.


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## Virginiagal (Apr 24, 2017)

I ran across something about Bermuda while looking for something else. Take a look toward the end: " Recommended limestone applications to achieve a soil pH of about 6.4 are shown in Table 3. If diseases such as take-all patch of bentgrass, summer patch of Kentucky bluegrass, or spring dead spot of bermudagrass are of concern, maintaining lower soil pH (5.4 - 5.7) may be desirable, and reduced or no limestone should be applied to achieve this level." I don't know how common spring dead spot is or if it's anything to be concerned about.
https://mda.maryland.gov/resource_conservation/Documents/consultant_information/2005%20I-E2%20p1-5%20s5.pdf

That led me to see what I could find about best pH for Bermuda and I found this which referred to a study saying Bermuda prefers 5.5-6.0. I looked but couldn't find the study it references.
https://turfexplorer.com/ph-for-bermuda-grass/

So, maybe you should consider not doing any lime?


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## Virginiagal (Apr 24, 2017)

@LushLife18 I'm tagging @Mightyquinn in case he has some insight on the best target pH for Bermuda. VA Tech has a target of 6.5 but what you have now, 6.1, might be better. He might know something about spring dead spot too. Did you see the Bermuda Bible in the warm season forum?
https://thelawnforum.com/viewtopic.php?t=1651


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## Mightyquinn (Jan 31, 2017)

Hello @LushLife18

SDS(Spring Dead Spot) in bermuda is rare and I wouldn't really concern yourself too much about it, I have my own theory on a cause of it but if I remember correctly there is no cut and dry cause behind it. As for the pH, at 6.1 you are fine and 6.5 is optimal and it what I am trying to shoot for in my lawn so if you already have the lime then go for it if not you can always add it later or even next year if you wish. I doubt your pH will move a whole lot anyway without the lime with your CEC and OM %. Bermuda is a pretty resilient grass and will grow a nice lawn in a wide range of conditions as long as it's getting 6+ hours of sun a day and you are feeding, watering and mowing it regularly is all it really needs to thrive and look good.


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## LushLife18 (May 10, 2021)

Mightyquinn said:


> Hello @LushLife18
> 
> SDS(Spring Dead Spot) in bermuda is rare and I wouldn't really concern yourself too much about it, I have my own theory on a cause of it but if I remember correctly there is no cut and dry cause behind it. As for the pH, at 6.1 you are fine and 6.5 is optimal and it what I am trying to shoot for in my lawn so if you already have the lime then go for it if not you can always add it later or even next year if you wish. I doubt your pH will move a whole lot anyway without the lime with your CEC and OM %. Bermuda is a pretty resilient grass and will grow a nice lawn in a wide range of conditions as long as it's getting 6+ hours of sun a day and you are feeding, watering and mowing it regularly is all it really needs to thrive and look good.


@Virginiagal @Mightyquinn Thanks for the in-depth thoughts and analysis on the option for amending with lime in preps for my Bermuda!

The other consideration is prepping for inter-seeding Bluegrass in the fall, since I am shooting for establishing a Bluemuda stand. From what I've read from some of the extension offices, KBG thrives at 6.5-7.

I already have the lime, so I will go ahead and apply it, with the goal to shoot for 6.5 or so. Thanks again for the advice!


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## Virginiagal (Apr 24, 2017)

Good luck to you! I think it is adventurous enough to do either a Bermuda establishment with all the short mowing every few days or a KBG overseeding into anything and here you are doing both. You can search for bluemuda on the forum and there is some discussion of it. You could send private messages to those that have tried it or post something and tag them to get their attention if you have some questions. Be sure to read herbicide labels carefully to see what's safe on what kinds of grass. I guess you're doing some weed killing now with glyphosate to kill off everything growing now, You have irrigation in place or at least a plan for hoses and sprinklers? Preemergents are wonderful but they will prevent your grass seed too so pay attention to rates and when protection will wear off.


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## LushLife18 (May 10, 2021)

Virginiagal said:


> Good luck to you! I think it is adventurous enough to do either a Bermuda establishment with all the short mowing every few days or a KBG overseeding into anything and here you are doing both. You can search for bluemuda on the forum and there is some discussion of it. You could send private messages to those that have tried it or post something and tag them to get their attention if you have some questions. Be sure to read herbicide labels carefully to see what's safe on what kinds of grass. I guess you're doing some weed killing now with glyphosate to kill off everything growing now, You have irrigation in place or at least a plan for hoses and sprinklers? Preemergents are wonderful but they will prevent your grass seed too so pay attention to rates and when protection will wear off.


Yep. Been reading and listening to Brian Winka and Dr. Gregg Munshaw's stuff on the bluemuda and a few others as well.

Irrigation system is going in just after the sod install. Will need it for the future KBG!

Thank you for the advice. It is much appreciated!


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## Virginiagal (Apr 24, 2017)

It's good you have some reading material on this. You could probably find some emails for Brian Winka and Gregg Munshaw. One thing I'd ask them is whether you should wait a year before the overseeding. I read one article and it seemed like they were doing this on well established Bermuda. They described fraze mowing (not for the faint of heart!) as prep for overseeding, and I can see how that would open up a seedbed for KBG. But should you do that on fairly new sod? Also, ask about the fertilizing. The article I read said 2-3 lb of nitrogen per 1000 sq ft for the whole year, consistently spring through fall. That doesn't seem enough for either Bermuda or KBG. How would you apply a very low rate? How often? I'm guessing they do it with spray instead of granules. But maybe small amount of a slow release granule fertilizer would work. While you're reading, do some reading on c3 and c4 grasses. KBG is c3 and Bermuda is c4. They do photosynthesis differently. Crabgrass, by the way, is c4 and that's why it can dominate in the summer against cool season grasses.


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