# Macros, micros, lime, the works



## rbvar (May 28, 2020)

Waypoint results from last week:










Background: Have been using a local lawn care company, basic every-other-month fert + Barricade + post-em program. This year, starting in May, I started supplementing what they were doing. In the off months, put down some granular 16-4-8 (plus humic and micros) at about 0.5#N/M. Between the service's granular applications and mine, I also did some liquid fert+kelp+micros applications, probably around 0.2#N/M each time. Every few weeks I'd do some mix of RGS, Air8, and D-Thatch. A home soil test in June showed PH around 5 and low NPK. Around 4th of July, put down a bag of Mag-i-Cal at the max rate of ~7.2#/M.

Since June, have been maintaining HOC around 1.25-1.75" with a manual reel. Was hoping to go lower this year, but realized too late how much the reel floats. Previously was using a rotary, but lowest setting there is 1.5" and was seriously scalping the slightly sloped and quite bumpy lot. Tried to be consistent with 1-1.5" water weekly with 3-4 days between watering, but weeks-of-drought then a week of solid rain pattern, plus the like 100 degrees all July surely messed with that.

Finally got tired of flying blind, so sent in soil sample to Waypoint. Will do it again at a more appropriate time like late winter, but wanted to see were things stood now.

Next steps:

1. PH still low. Ca low, Mg in optimum range, so I'm assuming I should stick with calcitic lime? Ok to get another application in this season, maybe mid Sept, or is 2.5 months not long enough between?

2. Waypoint recommendation for K: given texture class, guess this means 1#/M K2O this fall? And as S is a bit low, opt for SOP at 2#/M (minus whatever #s K the lawn service uses for their fall app)?

3. P: TSP this spring if I can find it?

4. N: Waypoint and my home test both showed no N. Assuming this plus low CEC means the bermuda is taking up whatever doesn't leach away? Should I be looking at heavy N apps next year? More foliar?

4A. August is an off month for the lawn service, and I have a bag of Scott's Green Max I got on sale ready to throw down this week. Any concern with that given Fe already high?

5. Micros: Anything I should be doing here? Ca would be going up with the lime, S with the SOP, right? How about the Boron? I am looking at next year doing a leveling project, 1/4" of Super Sod Leveling mix (70% sand, 30% Soil3). Is that additional OM likely to address low B?

Goal next year, now that I have a mower that (with enough multiple passes) can scalp super low in spring, to maintain 0.75 or 1" HOC. Anything else I should be putting in place or planning now?

Thanks!


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## Virginiagal (Apr 24, 2017)

Do you know exactly what the lawn company is applying and how much? Is there a reason you're not doing all the applications yourself? I would suggest having one person in charge of applications and writing down what was done when.

You need lime. For regular lime, you can put down 50 lb/1000 sq ft at a time, twice a year (fall and spring). You've done 7.2, leaving 192.8 to go. Do half in late fall (like November), half in the spring. Maybe you can find regular calcitic lime (Wake Stone has it in N.C. quarries so maybe it is distributed somewhere near you). If not, you can use dolomitic lime. You can continue use to use the fast acting calcitic lime but you'll be doing it for years to get to the total lime needed.

For the phosphorus needed, the easiest way is to use a balanced fertilizer like 10-10-10 for one application, where you put down 1 lb of N , 1 lb of P205, 1 lb of K2O per 1000 sq ft. That will leave you with 5 more lb of N over the year and 2 more lb of K2O to do. They suggest doing the phosphorus in the spring so you could plan the balanced fertilizer app for then.

You could do 1 lb of K2O this fall with SOP. Maybe do it on the month the lawn service isn't doing anything. With the balanced fertilizer app in the spring, that will leave you with 1 more lb of K2O to do over the growing season next year, which you might do with fertilizer that contains K or with a separate K2O app.

Don't worry about the N not showing up on tests. It jumps around. A test score means nothing. 6 lb of N a year is pretty heavy. Even without knowing what the lawn service is doing, it sounds like your grass has been getting a lot of N. High iron is not a problem, so ok to use the Green Max. The CEC is on the low side but it's not terrible. Generally for a low CEC you would do slow release fertilizer or spoon feeding. Don't increase the amount, just how it's spread out.

I would not worry about the boron. The compost you're using in your leveling mix may help. You can follow it on subsequent soil tests and see if it goes up or down.


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## Virginiagal (Apr 24, 2017)

You're aware that the compost component of your leveling mix will decompose? If leveling is the goal, it would seem to be more prudent to use stuff that won't decompose. Also there's the question of how well it's mixed. Maybe discuss this with the warm season forum?


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## rbvar (May 28, 2020)

Yeah, I should have paid attention all this year to what the service was applying, but didn't think of it until the application last month: July app was a 24-5-11 + 4% iron + Barricade, one full 50# bag so 1.5#N/M. Stuck with them this year for a couple reasons. One, it's a small outfit, just a couple guys and wanted to support them with everything happening this year (admittedly sounds like lawn/landscape has been less impacted than many other small businesses), plus I wasn't sure if I'd really be getting into this hobby. Other main issue is pre-em/disease control; been spraying with Ortho Dial, currently don't own or have practice with precise spraying. But I probably will take on everything next year.

Agree that the compost works against the leveling, so it's kind of a combined smoothing and soil health project. Honestly more of a top dressing/back-fill after core aeration, probably around 1/8" except in a few big dips and ridges where I twist my ankle. Actually started this plan on part of the lawn this year (and did vet the idea in the Warm Season forum), so this is completing that effort. Then 2022 look at the serious leveling project with 100% sand.

Guess in addition to soil test, I should mention problem areas. Common general issues with tract-built relatively new construction: compaction, buried rocks and construction debris. Screwdriver test doesn't look good if things have been dry for a while. Been addressing with mechanical and liquid aeration, and trying to promote root cycle. Overall, turf seems ok. Would like thicker, but thinking that a true spring scalp and 0.75-1" HOC (and maybe some verticutting) will promote that.

Do have one area, about 300 sq ft, that doesn't act like the rest. It just doesn't like to put on vertical growth. It gets same full sun as the rest of the back yard, there's no physical separation (above ground, anyway) between it and the rest of the back yard, soil there is no more compacted than the rest (in fact, it seems like on of the better areas of the back), it isn't the area that dries out first, so really not sure what's going on. It greens up fine, it seems as thick as the rest, pull test seems fine, no obvious bugs or disease, but while I have to mow like every 2-3 days to maintain 1/3rd rule on the rest of the lawn, when I get to this area the reel just spins, no blades high enough to make contact. It was the same last year with the rotary, blade was just hitting air.


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## Virginiagal (Apr 24, 2017)

If you are aerating, that is such a good time to apply lime so it gets further into the ground. The problem with liming at the time of seeding is the lime is on top of the ground with the seed and it could be quite alkaline right there and acidic underneath. So I suggest putting the 50 lb/1000 sq ft of regular lime (calcitic or dolomitic, whatever you can find) down immediately after aerating while the holes are the most open. The top dressing will provide some separation for the seed from the lime (assuming you top dress before seeding).


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## Virginiagal (Apr 24, 2017)

Could debris underneath be part of the problem with the 300 sq ft area? Could a metal detector help locate stuff? In areas near sidewalks I would suspect overflow of gravel into the yard area when they were creating the sidewalk. In particular problem spots it might be worth digging to see if you find an obstruction. Get them out if you can.


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