I've owned my house for 14 years. Over the 14 years, Milorganite was the primary N source. I did not use any other fertilizer, so no potassium was being put down over this time and I've been using SOP to raise potassium levels. 7k sqft of elite KBG and elite TTTF. The core grasses of my lawns are at least five years old (overseeded here and there over the years for fall repairs).
I always mulch-mow...14 years. In the spring/fall, I mow 2x a week to 3x a week, but I am experimenting with Trinexapac-Ethyl (a plant growth regulator that slows vertical growth) which would slow that rate to ~1x per week. In the summer, I slow down to every two weeks and try to time my cuts around when a cool period/rain period will take some of the edge off the stress from cutting.
My irrigation practices are evolving at the moment. I used to do none and I found that weeds move in and bits of my lawn would die. This year I would like to irrigate to prevent dormancy. It takes a full day to get down half an inch of water across 7k sqft and $20 in water. I don't think I can live with weekly watering of half an inch, but maybe every two weeks as needed. I don't have the experience with watering during the summer to know if 0.5" every two weeks is enough to prevent dormancy during drought. I would never water every day or frequently...only for renovation germination purposes.
I have a large blindspot in understanding lawn diseases and identifying them. I only know rust and powdery mildew. When my KBG lawns were young, they get both of those diseases during the inactive seasons and grow out of them during the active seasons. I could be missing diseases in the summer that are killing my turf and not necessarily drought. It's something I'm working to learn more about. All that said...I'm not aware of any chronic lawn diseases in my lawn that I'm concerned about.
I did have a significant grub problem in the summer/fall of 2021 (beetles were in my garden like crazy in the previous years) and that devastated my backyard lawn after the summer (that's what I believe happened). Longstory-short, I treated for grubs immediately and I have been putting down Scott's Grub-ex every year since in May. No problems since.
My inputs from the last 9 months:
*Note: the lbs per K is the actual product from the bag.
09/19/22 - 2 lbs per K Potassium Sulfate(SOP) (0-0-48)
09/20/22 - 3.57 lbs per K Elemental Sulfur
09/21/22 - 2 lbs per K Ironite
10/01/22 - 2 lbs per K Fast Acting Gypsum (Earth Science brand)
10/06/22 - 2 lbs per K Ironite
10/09/22 - Fast Acting Gypsum (Earth Science brand) 2 lbs per K
10/21/22 - 2 lbs per K Ironite
11/07/22 - 2 lbs per K Ironite
12/05/22 - 2 lbs per K Ironite
02/15/23 - 5.7 lbs per K Super Iron Plus (16.5% iron humate, 1% Manganese of which 0.4% is soluble, 2% total & soluble Magnesium)
03/23/23 - 51.43 lbs per K of traditional gypsum
03/24/23 - 5.7 lbs per K Super Iron Plus
03/24/23 - 17 lbs per K of Ammonium Sulfate (20.5-0-0 24% Sulfur)
04/05/23 - 17 lbs per K of Ammonium Sulfate
04/05/23 - 2 lbs per K Potassium Sulfate(SOP)
04/21/23 - 1 lbs per K Andersens Humic DG
04/21/23 - 1 lbs per K of Iron Sulfate (30% iron)
04/21/23 - 0.93 lbs per K of Ammonium Sulfate
04/21/23 - 0.5 lbs per K of SOP
04/27/23 - Grubex at the bag rate
05/24/23 - Soil cores pulled for THIS test.
06/02/23 - 2 lbs per k of SOP
Why the elemental sulfur? To lower the pH to the optimal range.
Why Gypsum? To leach magnesium and add calcium to balance the cal to mag ratio.
Goals:
In a year, I'd like to convert my lawns to a mono stand of KBG and fight quackgrass in the future with Certainty (Certainty kills TTTF if my understanding of the label is correct). I would like to perfect the soil nutrient balance to support the healthiest grass. I'm down for buying micronutrients and mixing them with Milorganite. I also have a nice battery backpack sprayer and a hand boom for blanket spraying FAS/KH/BLSC etc.
I have been concerned about the pH of my lawns over the years and I did my first and only treatment of elemental sulfur in Sept 2022. My front yard has come down from 7.0 to 6.8. My backyard is still high at 7.2 (prior Logan Labs tests had backyard pH at 7.3 to 7.5). The turf quality and color differences between the two lawns are something I notice. My target is 6.6 to 6.7 for pH. I plan to continue another elemental sulfur treatment. Let me know if you have thoughts for or against another elemental sulfur application.
I have been concerned with the Cal to Mag percentage ratios. Last year, I began using gypsum to leach magnesium and add calcium to try to balance the ratios. This might be ineffective and I'd love to understand what your thoughts are on fixing the cal:mag ratio in my specific circumstances.
Note: I have never used a lime product that would introduce magnesium. Only Super Iron Plus, but it was a tiny amount of magnesium and only a few bags. No plans to ever use it again. No idea where the high magnesium levels came from in my soil and they've been that way since 2011 (see 2011 Logan Labs Soil test below).
I would love to get a breakdown from you folks on what you think of my soil, where the target levels should be, and what to use to get there.
Thank you so much for taking a look!
The 2023 test was strictly 3" to 4" core depth only. (This is the standard I'll use going forward.)
The 2022 test was strictly 2" to 4" core depth only and I reported the depth as 3" to Logan Labs.
The 2011 test was pulled at approximately 6" and I reported the depth as 6" to Logan Labs.
May 2023 Soil Test:
Aug 2022 Soil Test:
Jan 2011 Soil Test Backyard Only:
