Lawn Seed Calculator

Lawn Seed is evaluated from Lawn Area, Grass Type and Seeding Type. The calculation reports Pounds of Seed, 5-lb Bags Needed and 20-lb Bags Needed.

Results

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About the Lawn Seed Calculator

Lawn Seed is treated here as a quantitative relation between Lawn Area, Grass Type and Seeding Type and Pounds of Seed, 5-lb Bags Needed, 20-lb Bags Needed and Seeding Rate Used.

The calculator uses a multi formula configuration. Each reported value is read as a direct evaluation of the stored rules with the declared field formats and units.

Formula basis:
Pounds needed = (area / 1,000) x seeding rate (lbs per 1,000 sq ft) x seeding type multiplier
New lawn: 100% of seeding rate
Overseeding (thin lawn): 50% of seeding rate
Heavy overseeding (very sparse): 75% of seeding rate

Interpret the outputs in the order shown by the result fields. Optional inputs affect only the outputs that depend on those variables.

Formula & How It Works

The calculation applies the following relations exactly as recorded in the metadata:

Pounds needed = (area / 1,000) x seeding rate (lbs per 1,000 sq ft) x seeding type multiplier
New lawn: 100% of seeding rate
Overseeding (thin lawn): 50% of seeding rate
Heavy overseeding (very sparse): 75% of seeding rate

Each output field is produced by substituting the supplied inputs into the relevant relation and then applying the declared rounding or text format.

Worked Examples

Example 1: New Kentucky Bluegrass lawn: 4,000 sq ft, Chicago area

Inputs

area: 4000 grass_type: Kentucky Bluegrass (cool season) seeding_type: New lawn (bare soil)

Pounds of Seed: 10 lbs. 5-lb Bags Needed: 2 bags. 20-lb Bags Needed: 1 bags. Seeding Rate Used: 2.5 lbs/1000 ft^2

With Lawn Area = 4,000, Grass Type = Kentucky Bluegrass (cool season) and Seeding Type = New lawn (bare soil) as the stated inputs, the result is Pounds of Seed = 10 lbs, 5-lb Bags Needed = 2 bags and 20-lb Bags Needed = 1 bags. Each value corresponds to the declared output fields.

Example 2: Overseeding Tall Fescue lawn: 8,000 sq ft, Charlotte NC, thin areas

Inputs

area: 8000 grass_type: Tall Fescue (cool season) seeding_type: Overseeding (thin existing lawn)

Pounds of Seed: 28 lbs. 5-lb Bags Needed: 6 bags. 20-lb Bags Needed: 2 bags. Seeding Rate Used: 3.5 lbs/1000 ft^2

With Lawn Area = 8,000, Grass Type = Tall Fescue (cool season) and Seeding Type = Overseeding (thin existing lawn) as the stated inputs, the result is Pounds of Seed = 28 lbs, 5-lb Bags Needed = 6 bags and 20-lb Bags Needed = 2 bags. Each value corresponds to the declared output fields.

Example 3: New Bermudagrass lawn: 10,000 sq ft, Dallas TX

Inputs

area: 10000 grass_type: Bermudagrass (warm season) seeding_type: New lawn (bare soil)

Pounds of Seed: 15 lbs. 5-lb Bags Needed: 3 bags. 20-lb Bags Needed: 1 bags. Seeding Rate Used: 1.5 lbs/1000 ft^2

With Lawn Area = 10,000, Grass Type = Bermudagrass (warm season) and Seeding Type = New lawn (bare soil) as the stated inputs, the result is Pounds of Seed = 15 lbs, 5-lb Bags Needed = 3 bags and 20-lb Bags Needed = 1 bags. Each value corresponds to the declared output fields.

Example 4: Overseeding with Perennial Rye for winter color: 5,000 sq ft, Phoenix AZ

Inputs

area: 5000 grass_type: Perennial Ryegrass (cool season) seeding_type: Heavy overseeding (sparse/patchy lawn)

Pounds of Seed: 30 lbs. 5-lb Bags Needed: 6 bags. 20-lb Bags Needed: 2 bags. Seeding Rate Used: 6 lbs/1000 ft^2

With Lawn Area = 5,000, Grass Type = Perennial Ryegrass (cool season) and Seeding Type = Heavy overseeding (sparse/patchy lawn) as the stated inputs, the result is Pounds of Seed = 30 lbs, 5-lb Bags Needed = 6 bags and 20-lb Bags Needed = 2 bags. Each value corresponds to the declared output fields.

Common Use Cases

Calculate grass seed for a new lawn
Determine overseeding rate for a sparse lawn
Estimate how many bags of grass seed to buy