Grass Seed & Sod Calculator - Lawn Estimator
Starting a new lawn or fixing patches? Calculate exactly how much seed or sod you need based on your lawn size and specific grass type with professional seeding rates.
Lawn Visualization
Lawn Details
Length × Width = Square Footage
Overseeding uses 50% less seed
Seeding Rate:
8 lbs per 1,000 sq ft (New Lawn)
Seeding Success Tips
Best timing: Early fall or early spring for cool-season grasses.
Water daily: Keep seed moist (not soaked) until germination.
Use a spreader: Ensures even coverage - don't hand-spread.
Seeding Option
Most Affordable
Estimated Cost: $40
Purchase Options:
- 1 Large Bags (20 lb)
- OR
- 3 Small Bags (3 lb)
Sod Option
Instant Results
Estimated Cost: $900
Coverage Details:
- Covers 1,050 sq ft (with 5% waste)
- Approximately 105 standard rolls
- 1 pallet = 450 sq ft coverage
Seed vs. Sod Comparison
| Factor | Seeding | Sod |
|---|---|---|
| Cost | $40 | $900 |
| Time to Usable Lawn | 6-8 weeks | 2-3 weeks |
| Installation Difficulty | Easy (DIY friendly) | Moderate (Heavy lifting) |
| Best Season | Fall or Spring | Spring through Fall |
| Variety Selection | Excellent (100+ types) | Limited (5-10 types) |
Don't Forget a Broadcast Spreader
For even seed coverage, a broadcast spreader is essential. Hand-spreading leads to uneven germination and patchy lawns.
Complete Lawn Seeding & Sodding Guide
Understanding Grass Seed Coverage Rates
Grass seed coverage rates vary significantly by species due to differences in seed size and germination patterns. Using the correct seeding rate ensures proper lawn density without wasting money on excess seed.
Standard Seeding Rates (per 1,000 sq ft):
New Lawn Installation:
- • Tall Fescue: 8 lbs
- • Perennial Ryegrass: 9 lbs
- • Kentucky Bluegrass: 3 lbs
- • Bermuda Grass: 2 lbs
- • Zoysia: 2 lbs
Overseeding Existing Lawn:
- • Tall Fescue: 4 lbs
- • Perennial Ryegrass: 5 lbs
- • Kentucky Bluegrass: 1.5 lbs
- • Bermuda Grass: 1 lb
- • Zoysia: 1 lb
Note: Rates based on University Extension Service recommendations. Bermuda and Zoysia have tiny seeds - a little goes a long way!
Choosing the Right Grass Type
Selecting the appropriate grass species for your climate and lawn use is crucial for long-term success:
Cool Season Best for Northern Climates
Tall Fescue
- • Deep roots, drought tolerant
- • Tolerates heat and shade
- • Low maintenance, bunching growth
- • Best all-around choice for most areas
Kentucky Bluegrass
- • Fine texture, dark green color
- • Self-repairing via rhizomes
- • Requires more water and fertilizer
- • Premium appearance, higher maintenance
Perennial Ryegrass
- • Fast germination (5-7 days)
- • Wear tolerant, good for play areas
- • Shiny, fine-textured blades
- • Often mixed with bluegrass
Warm Season Best for Southern Climates
Bermuda Grass
- • Extremely heat and drought tolerant
- • Aggressive growth, spreads quickly
- • Goes dormant (brown) in winter
- • Ideal for southern lawns, golf courses
Zoysia Grass
- • Dense, carpet-like growth
- • Low maintenance once established
- • Slow to establish from seed
- • Often installed as plugs or sod
Step-by-Step Seeding Instructions
-
1
Prepare the Soil
Remove debris, weeds, and old grass. Till or rake soil to 2-3 inches deep. Level the surface and remove rocks. For new lawns, add 2 inches of quality topsoil if needed.
-
2
Test and Amend Soil
Get a soil test ($10-20 at garden centers). Adjust pH to 6.0-7.0 with lime (if too acidic) or sulfur (if too alkaline). Add starter fertilizer according to test results.
-
3
Apply Seed with Spreader
Calibrate spreader to recommended rate. Apply half the seed walking in one direction, then apply the other half perpendicular. This ensures even coverage without gaps.
-
4
Rake and Roll
Lightly rake seed into top 1/4 inch of soil. Roll with a lawn roller (or walk over area) to ensure seed-to-soil contact. Don't bury seed too deep.
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5
Apply Mulch (Optional)
Spread 1/4 inch straw or erosion control blanket. This retains moisture, prevents erosion, and improves germination rates by 20-30%.
-
6
Water Consistently
Water lightly 2-3 times daily to keep top inch of soil moist (not soaked). After germination, reduce to once daily. After 3 weeks, transition to deep watering every 2-3 days.
Sod Installation Guide
Sod provides an instant lawn but requires proper installation for successful root establishment:
Before Delivery:
- Remove old grass and weeds completely
- Grade soil so it slopes away from buildings (1" per 10 feet)
- Soil should be 3/4" below walkways and driveways
- Apply starter fertilizer and water thoroughly one day before
Installation Day:
- Install immediately - sod begins dying within 24 hours of harvest
- Start along longest straight edge (driveway, sidewalk)
- Stagger joints like bricks - never line up seams
- Push edges tightly together without overlapping
- Roll with lawn roller to eliminate air pockets
- Water deeply immediately after installation (1 inch)
Watering Schedule
New Seed Watering
Week 1-2 (Germination):
Light watering 2-3 times daily. Keep top 1/2" of soil moist but not puddled.
Week 3-4 (Seedling Growth):
Reduce to once daily, deeper watering. Top 1-2" should stay moist.
Week 5+ (Established):
Transition to normal schedule: 1" of water per week, applied in 1-2 deep waterings.
New Sod Watering
Week 1 (Critical Period):
Water daily, 1" total. Sod and soil should be moist 4-6" deep.
Week 2 (Root Development):
Reduce to every other day. Check that roots are growing into soil below.
Week 3+ (Established):
Normal schedule: 1-1.5" per week. Water deeply to encourage deep roots.
Frequently Asked Questions
Q: What's the best time to seed a lawn?
A: For cool-season grasses (fescue, bluegrass, ryegrass), seed in early fall (September) or early spring (April). Fall is ideal because weeds are less active. For warm-season grasses (bermuda, zoysia), seed in late spring (May-June) when soil reaches 65°F+.
Q: How long until I can mow new grass?
A: Wait until grass reaches 3-4 inches tall (usually 3-4 weeks after germination). Mow to 2.5-3 inches on first cut. Make sure soil is dry enough that mower doesn't leave ruts. Use sharp blades to avoid pulling young plants.
Q: Can I walk on new sod or seed?
A: Avoid walking on seeded areas until grass is 3 inches tall and established (4-6 weeks). For sod, minimize traffic for the first 2 weeks, but light foot traffic for installation and watering is okay. Full use after 2-3 weeks when roots have anchored.
Q: Why is my grass seed not germinating?
A: Common causes: (1) Insufficient water - soil dried out, (2) Seed planted too deep (>1/4 inch), (3) Soil temperature too cold (<50°F) or too hot (>85°F), (4) Old seed with low germination rate, (5) Birds or erosion removed seed. Most grass germinates in 7-21 days under ideal conditions.
Q: Is sod or seed better for slopes?
A: Sod is much better for slopes steeper than 3:1 (3 feet horizontal to 1 foot vertical). Sod provides immediate erosion control and doesn't wash away in rain. If seeding a slope, use erosion control blankets or hydroseed, and seed in fall when rain is gentler.
Pro Tips for Success
- Buy quality seed: Cheap seed has low germination rates and more weed seeds. Spend an extra $1-2 per pound for certified seed.
- Don't overseed too heavily: More seed ≠ better lawn. Overcrowding leads to weak, disease-prone grass.
- Apply pre-emergent carefully: Don't use pre-emergent weed control within 8-12 weeks of seeding - it prevents grass seed from germinating too.
- Consider grass blends: Mixing 2-3 grass types provides disease resistance and better year-round performance. Example: 80% fescue + 20% bluegrass.