CaliTriDude Soil Test Results

[calitridude]

[andy10917]

Please write a paragraph or two about what your lawn's situation is, what your goals are, your current watering/mowing habits/etc. We can't help you if we have no idea what is currently being done and how/what you want to change...

[calitridude]

Phoenix Valley, Arizona
~1000 sf
Bermuda & winter rye grasses
Jar shake test settled out pretty homogenous - clay appearing
12" x 12" hole test drained >2 inches per hour

My soil often looks "parched earth" despite frequent watering and use of a general fertilizer. The soil seems to "crack" when it is dry, and is very hard.

"Tree side" sample grows under large mesquite trees with extremely limited direct sunlight
"Good lawn" gets direct sunlight

Bermuda grass does not grow under the trees (leaves me with 4 months of dirt for half the lawn), and the rest of the grass looks anemic
Winter rye does well throughout the whole lawn. I use manure and starter fertilizer when I put in my winter lawn.

I am wondering if I should transition to fescue or another grass species to get a year-round lawn, or if this is a soil issue?

Thanks all for the help!

[andy10917]

I went to interpret these tests, and found out that they are a year old. Is that right?

[calitridude]

That is correct. I had some difficulty posting initially, and gave up temporarily. I am looking to rehab the lawn now that we are settled in the home. Hoping for guidance do decide what species of grass to proceed with, whether to use seed or sod, and whether the soil needs to be augmented or simply rehabilitated. Thank you again.

[andy10917]

While the numbers look very different from one test to another, the general profile is pretty similar. There is a single number on the tests that is accounting for almost all of the differences. It's the TEC, which gives us the soil's nutrient holding capacity. It's far higher in the Tree area, and therefore the nutrients present are higher. This could be a higher amount of clay that you mentioned - in the Tree area.

The hardness and cracking are probably related to the very high amount of Magnesium in the soil - Magnesium in high amounts makes the soil "tight". Normally we would recommend the use of Gypsum to displace some of the Magnesium with Calcium, but that's not as easy when the Calcium is already at or near the full amount it should be at, with a high pH.

Since this is a lawn soil with its challenges coming from too much of Magnesium and clay, AND it is in the Southwest, I'm going to go out on a limb and recommend we give Gypsum a try for a year and see what happens. Look into whether "fast-acting" Gypsum is available in your area. If it is, get back to me. If not, we'll try standard "garden gypsum".

Not much else is wrong with the soil - once again, it's not easy to remove things that are too high.

I'm a little concerned about your use of the words "frequent watering" - could you please elaborate on that?

Lastly, Bermuda is a sun-lover and you're never going to get it to do well where there is shade. I can't offer how TTTF is going to do in your location and that soil, but I'm sure that Bermuda under trees isn't going to do well.

[calitridude]

Thank you for the input. I will see if the fast-acting gypsum is available. I have standard garden gypsum on hand. How often should one apply the gypsum?

Historically I have been watering daily, typically at night, for about 3-5 minutes depending on the time of year. I have not tested to see how deep the watering penetrates. I am currently between grass species, and so I am not watering as I wait for the Bermuda to finish going dormant.

[andy10917]

I will see if the fast-acting gypsum is available. I have standard garden gypsum on hand. How often should one apply the gypsum?

The amounts needed/applied will vary (a lot) by the type of Gypsum. The frequency will be around 90 days between apps.

Historically I have been watering daily, typically at night, for about 3-5 minutes depending on the time of year. I have not tested to see how deep the watering penetrates. I am currently between grass species, and so I am not watering as I wait for the Bermuda to finish going dormant.

That is exactly opposite of the recommended watering regimen: deep and infrequent. Watering should be around 1" of water, once a week. Use tuna cans or cat food cans to determine how long it takes to put down 1" of water. Warning: it could be a couple of hours.