CALCULATORS • IDENTIFIERS • GUIDES

Lawn Care Tools

Find the right tool to measure, identify, and care for your lawn.

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Measure Your Lawn

Find your lawn size with satellite measurement.

Spreader Settings

Get accurate spreader settings for your product.

Grass Seed Calculator

Calculate seed quantity and the right bag combination.

Soil Temperature

Check current soil temperatures in your area.

Soil Temperature Map

View soil temperature trends across the country.

Weed Identifier

Identify weeds and explore treatment options.

Disease Identifier

Diagnose common turf diseases and find solutions.

Grass Type Identifier

Identify your lawn's grass using blade shape, growth habits and regional clues. Coming soon

Lawn Calendar

Get personalized seasonal lawn care guidance. Coming soon

Fertilizer Calculator

Calculate how much fertilizer your lawn needs. Coming soon

Insect Identifier

Identify common lawn pests and treatment options. Coming soon

Seeding Wait Times

Find out when it's safe to seed after a treatment. Coming soon
LEARN & PLAN

Interactive Lawn Care Guides

Practical guides for seeding, feeding, and solving lawn problems—each with helpful next steps and an interactive planner.

Seed & establish

Build your seed + fertilizer sequence

Get a practical order of work for a new lawn or an overseed, with a check for fertilizer ingredients that can interfere with seeding.

Guide: What Do You Put Down First: Grass Seed or Fertilizer?

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Weeds & timing

Choose your weed-control or seeding priority

Choose the job that matters most and build a sequence that keeps weed control from working against your new grass.

Guide: Weed and Feed or Grass Seed First?

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Feed your lawn

Check St. Augustine feeding readiness

Check the conditions that matter before feeding St. Augustine, then see what to do next.

Guide: When to Fertilize St. Augustine Grass

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Weeds & timing

Calculate your label-based reseeding date

Turn the reseeding interval from your weed-killer label into a calendar date and a simple preparation checklist.

Guide: How Long After Weed Killer Can You Plant Grass Seed?

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Seed & establish

Find your overseeding direction

Compare overseeding directions for your current grass and light conditions, then explore matching Lawn Synergy seed options.

Guide: Best Grass Seed for Overseeding

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Seed & establish

Check whether your lawn is ready for seed

Walk through five practical checks and get the preparation tasks that your lawn still needs.

Guide: Can I Just Throw Grass Seed Down on Existing Lawn?

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Weeds & timing

Build a St. Augustine weed + feed approach

Check weed type, lawn condition, and feeding need before choosing a St. Augustine weed-control approach.

Guide: Best Weed and Feed for St. Augustine Grass

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Feed your lawn

Match tall fescue fertilizer to the job

Find a fertilizer direction for your tall fescue project, with a separate check for summer stress and overseeding.

Guide: Best Fertilizer for Tall Fescue Grass

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Weeds & timing

Build a Bermuda weed + feed approach

Choose a Bermuda weed-control direction and check whether feeding and weed treatment belong in the same visit.

Guide: Best Weed and Feed for Bermuda Grass

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Seed & establish

Plan a patch repair and seed quantity

Measure a repair area, enter the rate from your seed bag, and see the amount needed for each spreading pass.

Guide: Best Grass Seed for Patches

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Feed your lawn

Check the next feeding step for new grass

Check your new grass stage and previous fertilizer use before deciding whether the next step is feeding, waiting, or checking the label.

Guide: When to Fertilize New Grass Seed

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Regional planting

Explore your California seeding window

Explore a California planting window by grass type and region, with a month-by-month planning strip.

Guide: Best Time to Plant Grass Seed in California

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Weeds & timing

Build a grub-repair readiness plan

Work through the treatment, label, and seedbed checks that determine your next step after grub damage.

Guide: How Soon After Treating for Grubs Can You Plant Grass Seed

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Feed your lawn

See what 13-13-13 actually supplies

Compare the nutrients delivered by 13-13-13 and two other analyses at the same entered nitrogen amount.

Guide: Is 13-13-13 Fertilizer Good for Lawns?

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Weeds & timing

Plan seeding after your 2,4-D treatment

Enter the reseeding interval from your 2,4-D product label and turn your most recent spray date into a planning date.

Guide: How Long After Spraying 24d Can I Plant Grass Seed?

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Seed & establish

Compare tall fescue mixing directions

Compare a tall fescue blend, a bluegrass mix, and a shade-oriented option against what you want from the lawn.

Guide: Best Grass to Mix with Tall Fescue

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Seed & establish

Check whether new grass is ready for traffic

Check visible establishment milestones and the type of traffic you want to allow before reopening a seeded area.

Guide: How Long After Planting Grass Seed Can You Walk on It?

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Regional planting

Find an Illinois seeding window

Compare the regional Illinois planting window and check how your selected month fits a cool-season seeding project.

Guide: Best Time to Plant Grass Seed Illinois

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Feed your lawn

Choose a post-aeration feeding path

Build a post-aeration sequence for an established lawn or an aeration-and-overseeding project.

Guide: Best Lawn Fertilizer After Aeration

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QUICK ANSWERS

Lawn Care Tools FAQs

Get clear answers to common questions about grass seed, overseeding, fertilizer, and using our lawn care tools.

How do I calculate how much grass seed I need?

Measure the lawn area first, then use the Grass Seed Calculator with the application rate for your chosen seed and project. Overseeding and establishing a new lawn can require different rates. Check the current seed label rather than assuming every blend uses the same amount.

Should I use the same seed rate for bare patches and overseeding?

Not necessarily. Bare patches generally need a different rate from overseeding an existing stand. Use the seed bag's directions for the specific project and lawn conditions; spreading more than directed is not a shortcut to stronger turf.

Can adding extra grass seed fix poor establishment?

No. More seed cannot make up for poor seed-to-soil contact, unsuitable conditions, or inadequate moisture. Too much seed can crowd seedlings. Prepare the surface and use the rate recommended for your grass seed.

Do I need to aerate every time I overseed?

Not automatically. Match your preparation to soil compaction, thatch, existing turf, and surface conditions. The goal is good seed-to-soil contact. An aeration step may help some lawns, but it is not required for every overseeding project.

Can I apply grass seed and fertilizer on the same day?

They may be applied during the same project when the fertilizer is appropriate for seeding. Use separate application passes so you can control the seed and fertilizer rates. Prioritize soil contact and consistent moisture, and confirm that any added herbicide does not restrict establishment.

Can I use weed and feed while planting grass seed?

Only when the exact product label permits that grass species and seeding schedule. Weed-and-feed products can include herbicides that restrict germination or injure newly established grass. Do not treat them as interchangeable with plain or seed-compatible fertilizers.

Can I use pre-emergent fertilizer before overseeding?

Check the exact product label and its reseeding restriction. Many pre-emergent products are intended to prevent seed germination and can interfere with establishing desirable grass. Use a seed-compatible plan when overseeding.

How long should I wait to seed after spraying weed killer?

There is no universal waiting period. Identify the exact herbicide product and follow the reseeding interval and other restrictions on its current label. Rain, extra watering, or aeration do not automatically shorten that period. If you do not know what was sprayed, obtain the application record first.

How do I choose the right type of grass seed?

Match the grass to your climate, sun exposure, site conditions, and maintenance needs first. Germination speed alone does not determine long-term success. Compare the seed blend's label and regional suitability before purchasing, especially if repairing an existing lawn with a different grass species.

When is newly seeded grass ready for foot traffic?

Seeing the first seedlings does not mean the area is established. Give the grass time to build roots and coverage. Check soil firmness, rooting, turf density, and recovery before allowing repeated traffic, pets, or play. A first mowing is a useful checkpoint, not automatic clearance.