Interpreting Soil Test Results
So here are the results for the soil. I took it from a dead patch on the lawn (Bermuda). According to the test I have basic soil and low nitrogen, typical Arizona lawn conditions. The test says that Bermuda grows best in soil that is 6-7 on the pH scale. So I'm thinking I will be adding blood meal (for increased nitrogen) and something to lower the pH. Any second opinions on that? Or is there a product that can do both at once?
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If the soil test indicates it is near 8, then the usual thing to do is to add sulfur in increments to lower pH one point at a time. The amount you need depends on your soils' cec. Sandy soils need less than clay. To take the pH down from 8 to 6.5 would take in Sandy soil = 30 lbs, clay = 45 lbs of elemental sulfur spread over 1000 sq ft by a drop spreader.
You would have to measure the area you need to amend and calculate how much sulfur you actually need. Usually, to drop it a point at a time, it would be best to apply half the sulfur and retest in about 6 months. It takes that long for the sulfur you add to be used by the soil organisms to affect soil pH. If it is moving in the right directions, add the rest.
Sulfur does bring the pH down, but you will probably have to add it again at regular intervals because if your soil is basically limestone because of the geology of the area, you cannot alter that permanently.
What you can do to help plants grow better is to add an acidic amendment or compost. Peat moss is an acidic amendment that will help keep the pH higher longer. The alternative would be to get an acidic compost or make your compost more acidic by adding sulfur to the compost and spreading it.
Compost does a lot for the soil. It will help to retain moisture and grasses are among the thirstiest plants around. Compost will feed the soil web, and that will keep your grass healthier and hold on to nutrients better. Most of all compost has buffering capacity. It can buffer the pH of the soil so that even if the pH measures in the extreme range, it will behave more like it is neutral. It does help if you can find an acidic or at least neutral compost. Most composts will test at a pH near 8.0 unless it is made up of mostly acidic feed stock like oak and pines.
A friend makes compost for me and I told her that I could not use the compost unless it was more neutral since the soil pH was already alkaline at pH 7.8 and the plants were showing it. So she started adding sulfur to the compost while it was being made, it did not affect the quality or the speed that the compost was being made and it did ultimately end up with a compost that tests at near neutral pH of around 7.2.
You would have to measure the area you need to amend and calculate how much sulfur you actually need. Usually, to drop it a point at a time, it would be best to apply half the sulfur and retest in about 6 months. It takes that long for the sulfur you add to be used by the soil organisms to affect soil pH. If it is moving in the right directions, add the rest.
Sulfur does bring the pH down, but you will probably have to add it again at regular intervals because if your soil is basically limestone because of the geology of the area, you cannot alter that permanently.
What you can do to help plants grow better is to add an acidic amendment or compost. Peat moss is an acidic amendment that will help keep the pH higher longer. The alternative would be to get an acidic compost or make your compost more acidic by adding sulfur to the compost and spreading it.
Compost does a lot for the soil. It will help to retain moisture and grasses are among the thirstiest plants around. Compost will feed the soil web, and that will keep your grass healthier and hold on to nutrients better. Most of all compost has buffering capacity. It can buffer the pH of the soil so that even if the pH measures in the extreme range, it will behave more like it is neutral. It does help if you can find an acidic or at least neutral compost. Most composts will test at a pH near 8.0 unless it is made up of mostly acidic feed stock like oak and pines.
A friend makes compost for me and I told her that I could not use the compost unless it was more neutral since the soil pH was already alkaline at pH 7.8 and the plants were showing it. So she started adding sulfur to the compost while it was being made, it did not affect the quality or the speed that the compost was being made and it did ultimately end up with a compost that tests at near neutral pH of around 7.2.