The Lawn Spreader Triangle calculator computes the number of bags of lawn treatment (grass seed, weed killer, lawn fertilizer) that are needed for a triangular lawn based on the manufacturer recommended area of coverage per bag and the length of the three sides of the lawn.
INSTRUCTIONS: Choose units and enter the following:
- (A) Lawn Side A
- (B) Lawn Side B
- (C) Lawn Side C
- (BC) Coverage per Bag
How Many Bags (nB): The calculator returns:
- (n) Number of Bags Needed to treat the lawn
- (A) Square footage of Yard
- (Ac) Area of Yard in Acres
The Math / Science
Few lawns are perfect triangles that be accurately measured by the length of three sides. However, it's often a reasonable way to start, and one can approximate complex areas by sectioning them. For more complex lawn size measurements, see below.
Lawns require seed and then regular treatment to have thick grass with few or no weeds.
Lawn Care Product Coverage
The following table is for reference only and based on the manufacturer's published product coverage information. Please recommend additions or corrections.
Square Feet per Bag
Lawn Care Product |
Bag Size |
Coverage |
Scotts Turf Builder (Halts CRABGRASS PREVENTEER) |
13.35 lb |
5,000 ft2 |
Scotts Turf Builder (Triple Action 1) |
11.31 lb |
4,000 ft2 |
Scotts Turf Builder (Fall) |
11.43 lb |
4,000 ft2 |
Scotts Turf Builder (Winterguard Fall Lawn Food) |
37.5 lb |
15,000 ft2 |
Scotts Turf Builder Sun & Shade Mix Grass Seed |
20 lb |
8,000 ft2 |
Pennington Contractor Mix Grass Seed |
40 lb |
3,300 ft2 |
PLEASE RECOMMEND OTHERS! |
TBD |
TBD |
The treatments for lawns often come in the form of bags of treatment (seed, weed killer, fertilizer) from the home improvement store (e.g. Lowe's). The common practice for the manufactures is to list the square feet covered by the application of one bag. This calculator will tell you how many bags you need.
The formula for the number of bags of lawn treatment needed is:
nB = A / BC
where:
How big is your yard?
If you know the dimensions of the lawn, you can enter them in one of the calculators listed here to compute the square footage of the lawn.
Size of Land Calculators
Using Google Maps to Measure Your Lawn
One great tool for measuring the size on a yard is Google Maps. Find your home, and then right click on the screen. The last option is "Measure Distance". If you use this, to outline your yard, you will also get the square feet within the outline in an info box (see image of our yard). Our yard, indicated 110,138 ft2 . If we want to treat it with, the Fall Lawn Food (above) that covers 15,000 ft2 per bag, we enter 110138 ft2 (A) in the calculator and 15,000 ft2 (BC) in the calculator to find that we need 7.3 bags. So I'll buy 8 to be safe.
- Mowing Calculator: Estimates the distance walked, area covered, calories burned mowing and time required to mow an area of grass based on mower cutting deck width, speed and whether its a push mower or riding mower.
- Lawn Spreader Calculator: Computes the number of bags of lawn treatment (grass seed, weed killer, lawn fertilizer) are needed for a lawn based on the manufacturer recommended area of coverage per bag and the area of the lawn.
- Lawn Spreader Triangle: Computes the number of bags of lawn treatment needed for a triangular lawn based on the manufacturer recommended area of coverage per bag and the length of the three sides of the lawn.
- Lawn Spreader Rectangle: Computes the number of bags of lawn treatment needed for a rectangular lawn based on the manufacturer recommended area of coverage per bag and the length and width of the lawn.
- Lawn Spreader 4 Sided (non-Square): Computes the number of bags of lawn treatment (grass seed, weed killer, lawn fertilizer) needed for a four sided lawn based on the manufacturer recommended area of coverage per bag and the length of the four sides and diagonal of the lawn.
- Lawn Spreader 5 Sided:: Computes the number of bags of lawn treatment (grass seed, weed killer, lawn fertilizer) needed for a five sided lawn based on the manufacturer recommended area of coverage per bag and the length of the five sides and two diagonals of the lawn.
- Grass Seed Calculations use SPREADER calculators above with the grass seed specifications from the manufactures.
- New Sod Calculator: Computes the number of sod pieces needed for an area based on the size of the pieces of sod.
- New Sod Triangle: Computes the number of pieces of sod needed to cover a triangular shaped area such as a yard or field.
- New Sod Rectangle: Computes the number of pieces of sod needed to cover a rectangular shaped area such as a yard or field.
- New Sod 4 Sided: Computes the number of pieces of sod needed to cover a four sided (not squared) shaped area such as a yard or field.
- New Sod 5 Sided: Computes the number of pieces of sod needed to cover a five sided shaped lawn area such as a yard or field.
- New Sod Circle: Computes the number of sod pieces required to cover the given diameter of a circle.
- New Sod Oval: Computes the number of sod pieces required to cover an oval. It also provides the oval area and perimeter.
- Straw Cover Area Calculator: Computes the number of regular square-bales of straw needed to cover an area such as a field or garden for new grass seed. The common bales are 2 string square bales of 14"x18"x"36" inches weighing between 40lbs and 60 lbs.