[Alex1389]

Hey All! I'm hoping you guys can help me out here with my soil test results.

I've attached two soil test results that I've conducted this year through Soil Savvy. The first test was on 4/4/18 (w/ the 5.58 pH), and the second test was on 5/11/18 (w/ the 4.99 pH).

1) Any recommendations on an N application? I'll be dropping some 19-0-0 w/ Dimension here soon, and I dropped half bag rate of Milorganite last week. I was thinking of dropping another half bag rate of Milo in June and calling it quits with the N until late August. I'll also hit the lawn with Greene County Greene Effect 7-0-0 at 6-9 ounces per thousand every 4 weeks. Should I skip the June Milo and save it for July instead or skip the Milo altogether until Fall?

2) I've been applying fast acting lime (purchased at Lowe's and Home Depot). I've applied these products three times since April so far at about 8-10 pounds per thousand. Should I keep this up through the summer? Is all this rain making my soil super acidic? A soil test I had conducted last Fall had my pH around 6.

3) My K levels seem to be a consistent issue. They were very low when I measured last year as well. Is it safe to apply a 0-0-50 SOP at this time of year or should I wait until the Fall? Any concerns with increasing my sulfur levels with the SOP?

Lastly, I plan on using RGS, Air8, Greene Effect and maybe D-Thatch throughout the year about every 4 weeks, so I'll likely get small doses of N and K through those products.

Aside from all of the soil issues, the lawn looks OK. I just really want to take it to the next level this Fall or next Spring. I also want to make sure I get the soil right, as I'm planning a partial backyard reno (about 3k sq ft) due to some zoysia invasion.

I appreciate any and all input!!

 

[stotea]

From what I've read, N doesn't stay in the soil very long. So N readings from soil tests are essentially pointless. Just apply the usual 1 lb/M/month or whatever.

 

[g-man]

If you have irrigation, then you could continue the 1lbN/ksqft/month, otherwise go with half a pound or none. There is no point in pushing for grow and not being able to provide water.

SOP could go at anytime except the late fall.

 

[Alex1389]

@stotea Yep -- not too worried about the N. I can always bring that up easily.

@g-man Thanks, g-man. I'll throw down some SOP and test everything again in July. Think I should keep applying this lime monthly or just try to dump a ton of dolomitic lime onto it in one shot?

 

[g-man]

I prefer not to advise from soil savvy. I don't want to recommend something that turns out being bad for your soil or lawn. Their recommendations did not include lime.

 

[Alex1389]

@g-man no worries, thanks for your help. The Soil Savvy tests leave a lot to be desired. I saw your recommendations of a few labs on another thread and will check those out as well as checking with my local extension office for options.

Have a great holiday weekend!

 

[Alex1389]

Posted these over in my journal but figured I'd drop them here as well in hopes that a soil expert can help out

Specifically on the 'back lawn' tests, I'm curious if you guys think I can go ahead with a renovation this year or if I should hold out and fix deficiencies first...

 

[Suburban Jungle Life]

Woah! That's a big difference in ph from soil savvy! Did you lime?

 

[g-man]

Im on the cell in a work meeting. One thing that I recommend, stop the lime applications. Your pH is fine and if there is still lime to be process from your applications then it could still increase.

You still could use more potassium.

I noticed that you payed for their recommendations. Im not sure I agree with them. Mainly their k-mag one. I would need to think about it.

 

[ken-n-nancy]

Specifically on the 'back lawn' tests, I'm curious if you guys think I can go ahead with a renovation this year or if I should hold out and fix deficiencies first...

First off, all of those areas have soil that is in pretty good shape. Many folks have soil that would require years of remediation to get to a soil with those test results. The soil in the "back lawn" is definitely capable of supporting a successful renovation. Other than the low potassium, it's basically at target levels for the primary nutrients and is a sandy loam.

The pH and calcium levels that you have indicate that lime isn't needed, which was not the case in the soil savvy tests. I'm curious as to if you've been continuing to apply lime regularly since the earlier posts in this thread? That would explain the increase in soil pH since that time. If you haven't been applying lime since then, I would very much question the soil savvy test results.

Your soil composition is basically a sandy loam. Potassium isn't held particularly well in a sandy soil; accordingly, regular potassium applications (sulfate of potash) are likely to just be a part of your normal lawn care maintenance, just as regular nitrogen applications are for everybody. This year, I read an article, (Soil and Applied Potassium) which contains a key quote in regard to potassium for those on sandy soils:

Loss of potassium by leaching is one reason sandy and organic soils often test relatively low in available potassium, especially when tested in the spring. These soils require precise annual potassium applications, since it is not possible to build up high potassium reserves.

After 5 years of soil tests and regular SOP (sulfate of potash) applications on our lawn, I have come to terms with the fact that regular SOP applications will be a fact of life for me, as a lawn-care enthusiast, unless I replace the soil in our lawn to have markedly more clay in it! You're in the same situation. This isn't a problem, just a fact of life. Indeed, golf course greenkeepers on sand-based greens just make regular potassium applications -- it's not a bad thing, just the way it is. I make a regular monthly application of sulfate of potash at 1#K/ksqft from May through August each year. (I avoid fall applications of significant potassium as they have been correlated with increased snow mold risk in northern climates.)

I'm curious about the Logan recommendation for the Sul-po-mag. My presumption is that they are seeking to raise the magnesium a little bit, while also helping address the potassium need. However, you don't really have a magnesium deficiency (it's just the tiniest bit low), so I'd probably just stick with the SOP to tackle the potassium need.

In all honesty, I think the other big issue to be addressed anywhere on these test results is the low phosphorus on the side lawn. Your regular Milorganite applications should address that over time, but personally I'd use the opportunity to make a single application of a decent starter fertilizer on the side lawn in late August (most states prohibit phosphorus application to established lawns without a soil test indicating a need for phosphorus).

The high sodium level on the side lawn is also atypical. I have high sodium in our front lawn, presumably from salt usage on the road. Any idea what is responsible for your high sodium level on the side lawn? The sodium level on the side lawn is the only outlier in the cations for all three lawn areas -- if not for that one difference, all three areas are giving essentially the same result in the cations, and can all be treated identically. Depending upon the explanation of that higher sodium level, I'd skip the gypsum application to the side lawn and let natural leaching (you get a fair bit of rain in NJ) take care of lowering that sodium level.

 

[Alex1389]

@Suburban Jungle Life @g-man @ken-n-nancy

I've added about 15 #/k fast acting calcitic lime to the back and side yards and 25 #/k of the same to the front yard. Definitely done with lime for now! Although I'm not sure I still believe those results -- I limed about 3/4 days before I pulled the soil probes so I'm wondering if there were still any prills left in there (despite my attempts to take the sample from a lower depth.

I'm definitely going to be adding SOP... can I get away with 2 #/k through the rest of the year or should I stick with 1 #/k?

Appreciate everyone's help and the thorough write-up @ken-n-nancy!

I'll drop some starter fert here in early September as well to help out with the Phos deficiency on the side yard.

As for the elevated sodium on the side lawn, the parkway there is adjacent to a main road. I'm thinking that is from salt usage on the roads.

 

[ken-n-nancy]

I'm definitely going to be adding SOP... can I get away with 2 #/k through the rest of the year or should I stick with 1 #/k?

1#K / ksqft per month in the growing season will supply all the potassium your turf will need. There's not a lot of benefit to applying more than that on a sandy soil; the excess is likely to just leach away rather than being stored up in the soil.

Note that some studies on cool season turf in northern areas have linked fall potassium applications with increased risk of snow mold. If you've ever had issues with snow mold, I would discourage potassium applications within about 4-6 weeks of when freezing temps typically start in your area. (Here in NH, I don't apply any potassium after Labor Day.)

1#K / ksqft would be 2# of SOP / ksqft. (SOP is 0-0-50), so two pounds of product is needed to provide 1#K / ksqft.

As for the elevated sodium on the side lawn, the parkway there is adjacent to a main road. I'm thinking that is from salt usage on the roads.

Well, that explains it. Unless you are seeing damage to the turf from the salt, I personally wouldn't bother with the gypsum application.

 

[Alex1389]

I'm definitely going to be adding SOP... can I get away with 2 #/k through the rest of the year or should I stick with 1 #/k?

1#K / ksqft per month in the growing season will supply all the potassium your turf will need. There's not a lot of benefit to applying more than that on a sandy soil; the excess is likely to just leach away rather than being stored up in the soil.

Note that some studies on cool season turf in northern areas have linked fall potassium applications with increased risk of snow mold. If you've ever had issues with snow mold, I would discourage potassium applications within about 4-6 weeks of when freezing temps typically start in your area. (Here in NH, I don't apply any potassium after Labor Day.)

1#K / ksqft would be 2# of SOP / ksqft. (SOP is 0-0-50), so two pounds of product is needed to provide 1#K / ksqft.

As for the elevated sodium on the side lawn, the parkway there is adjacent to a main road. I'm thinking that is from salt usage on the roads.

Well, that explains it. Unless you are seeing damage to the turf from the salt, I personally wouldn't bother with the gypsum application.

Thanks again! I'll throw 1 #/k down now, again in mid-August, and the last one in mid-September and re-test everything in the spring. Appreciate your help!

Parkway lawn looks fine outside of the area overtaken by orchard grass.