Sodding materials can vary depending on the region you live in. Soil
conditions change throughout the world, and grass varieties are chosen
by sod farms to thrive in the areas they service.
Where I live there is good quality, and cheap soil. This is due to western cities expanding into farming areas, but this may be the opposite in your area.
In rocky sections of the east coast soil is often expensive, as it is trucked in from far away.
Loam is usually sold by the yard, and sod is usually sold by the square foot, or roll. It isn't difficult to calculate how much sod you will need once you know the dimensions of your area, but topsoil is a little more challenging.
The importance of good soil
Before we get into estimating sodding materials, we first want to discuss the soil you already have. We also want to discuss the importance of a good base of soil.
It's been said in landscaping many different times and ways, you don't put a $20 dollar plant in a $2 dollar hole.
The same thing goes for a healthy lawn. Don't cheap out on soil.
Spreading an inch or two of loam over a heavy clay base is not going to bring you long term success.
It will bring you long term grief instead.
If you have good soil that is rich in nutrients and not heavily compacted, you may not need a lot of loam (if any at all).
However, if you are renovating an existing yard, the lawn may have been in poor shape for a reason, and now is the time to correct it.
Your Goal with Soil
To have a successful lawn for the long term you need to have good soil composition, along with the proper PH balance. "Loam" is just a healthy mixture of rich organics, sand, clay or other fine sediments. Loam has the ability to take moisture relatively easily, and retain it as well.
When this balance is off with excessive sand or clay, it is called "Clay Loam", or "Sandy Loam" accordingly.
Combined with proper lawn care, this soil will allow you to have a nice thick, lush, green lawn with deep roots. Your lawn will combat weeds, drought, heat, cold, pests, and diseases much better. It will also require less chemical treatments and fertilizers saving you money and the environment.
A nice rich loam also has billions of microscopic organisms called microbes. Microbes turn the building blocks into soluble foods for the root system. For those of you that practice organic fertilizing, these microbes are vital in breaking down organic fertilizers to feed the roots.
Generally, the east cost of North America has a more acidic soil from the rains. The dryer regions of the west tend to have a more alkaline soil. You should have your soil tested before you begin if you are unsure of what the conditions are.
If you can, try to test at different locations in your yard. (The conditions can vary from point to point.) You can purchase soil test kits from most garden centers to measure the pH level of your soil. pH is a number scale to measure if you soil is acidic (below 7), neutral (7), or alkaline (above 7).
Most grasses do well with a pH level of around 6 or 7, but it's up to you to know what's best for the variety you are using. The lower the pH number the more acidic your soil will be.
If your soil is too acidic, you will want to bring up the pH level by applying lime. This will help neutralize the acidity. The effectiveness of the fertilizer will be reduced when pH is not in the right range. Your lawn will not respond to the fertilizer, with adequate growth and color changes.
It's important not to raise the pH level too fast, or too much at
one time either. This can have damaging effects on your lawn. If the
soil is very alkaline, than you may have to use sulfur, or an iron
sulfide enriched fertilizer to lower the pH level.
If you want to know if you have clay soil, take a handful of dirt and squeeze it into your hand. Clay will stay together in a tight ball when you roll it around.
Clay soil is very poor for draining water, and contains very little oxygen. If you have a lot of clay in your soil you should remove enough of it from your yard to allow for about six inches of loam, or amend it by tilling in organics.
Tilling and amending soil
If your budget is limited, and loam in your area is very expensive, you can make your own loam. use the dirt you already have and till in amendments. There are many different amendments you can use. Check with your garden center or landscape supply store to see what the have available to use.
I have grown some beautiful, lush, thick, and green lawns creating my own loam, at a fraction of the cost of trucking in large amounts.
Tilling can be very hard work, so be prepared for it. If your soil is parched, dry, and hard, soak the area to be tilled one or two days before you till. Don't till when it is wet or soaked, let it partially dry out for a day or so. This will make tilling a little easier.
Till down six to eight inches if you can, and break up the hard packed dirt underneath. This will allow you to remove large rocks that may impede root growth (one to two inches in diameter). Tilling will loosen up the soil so the grass roots can penetrate deeper into the ground. It will also allow oxygen and water to penetrate the root system much more effectively.
Add in your amendments and till the area again thoroughly so you have a consistent quality soil. If your soil is very heavy with clay, you can add sand and organics to break up the consistency of the clay to improve drainage. Again, your goal is to build a nice rich loam. If squeezed in your hand it will form a ball, but will crumble apart when your roll it around.
Using organics is the best soil building amendment.
Hopefully, now you have a better understanding of soil, and the importance of having the proper depth of good soil? You may spend a few hundred dollars more up front for an extra load or two of loam, but you will save that in the long term having a much healthier and environmentally friendly lawn.
To estimate the amount of loam requires you to know the dimensions of your area. You also need to know that loam can compact more than almost any other material. The compaction rate of soil is usually around 30%.
This means that whatever estimate you end up with, you will have to order additional amounts.
If not, you will find your soil depth too shallow for healthy root growth.
Loam is usually sold by the yard. To convert cubic feet to yards, divide the cubic feet by 27.
An area that is 40 ft. Long by 40 ft. wide and has a requirement of 6 inches of loam will look like this.
40 ft. x 40 ft. = 1600 sq. ft. times a depth of 6 inches (.5 of a foot) = 800 cubic ft.
Divide this by 27 (Conversion factor from cubic ft. to yards) = 29.62 yards of loam.
If you are curious on how we got the (.5 of a ft.) just take the inches and divide by 12. (12 inches in a foot)
Depending on whether the trucks are a single axle or tandem axle, it could be a 10, 12, 14, or even a 16 yard load. I would suggest adding a few yards to this number to account for compaction, and round it off to 32 yards. (A little bit more won't hurt you, but not enough will).
When it comes to ordering sodding materials, you need to know the square footage of the sodding area. Your supplier will be able to tell you how much you will need from your square footage estimate. This is a calculation you have already made from estimating soil.
Wastage from cutting
Make sure you when buying sod you add on about 3% to 5% to your order. You will be cutting sod for curves and other places giving you some wastage.
If you have a curvy yard, go with 5% to 8% in wastage. You will be able to use some of the wastage pieces for filling in here and there. Try not to use the really small scraps. Small pieces have a much harder time establishing when used around perimeters.
If you have a sod farm that sells direct to the public, you can eliminate the middle man to save more money. Sod is very heavy so plan on having it delivered, even if you own a half ton truck. (It will cost you more in fuel from multiple trips, and repairing broken springs than the delivery charge.)
There are probably a few dozen different varieties of grass in the world depending on where you live. Fortunately, the suppliers do all the leg work on finding the ones suited best for your purpose and region.
Ask around or visit a few different suppliers and check on their record of service when you can. Hopefully, you find one that has been consistently providing high quality sod in your area for years. You may find smaller suppliers that have good quality sod as well.
There are lesser quality suppliers with anything. With sod, you will find the quality is poor, and they have inconsistent cuts. (This makes it harder to work with.)
The last thing you will require for materials will be a good starter fertilizer. This will encourage root growth for you newly laid sod. The coverage amounts should be included on the bag itself. (If not put down a couple of pounds for every thousand square feet or so.)
Now we have covered Sodding Materials we can move, onto grading your yard...
Table of Contents: Sodding a Lawn
A. Sod Site
E. Laying Sod