Methodology

The GrassDx
Lawn Health Index

A transparent, five-dimension scoring system that tells you exactly how your lawn was evaluated — and what each number means.

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Why we built a named scoring system

Most lawn tools tell you "the AI analyzed your lawn." That is not a methodology. We wanted something you could hold us to — a defined set of criteria, applied consistently, that you can read, question, and understand.

The Lawn Health Index scores your lawn from 0 to 100 across five visual dimensions. Each dimension has a defined weight. The final score is a weighted average — calculated the same way every time, for every lawn, regardless of grass type or region.

The formula
LHI Score = (Coverage × 25%) + (Disease × 25%) + (Weeds × 20%) + (Stress × 20%) + (Urgency × 10%)
Five dimensions

What we look at

Every dimension scores from 0 to 100, where higher always means better. All five are assessed from the photos you upload.

1

Coverage & Density

How evenly and fully is your lawn covered? Bare patches, thin areas, and dead zones all reduce this score.

100 = lush, wall-to-wall coverage with no visible bare soil. 0 = bare or dead across most of the lawn.

25%
2

Disease & Pest Pressure

Are there visible signs of fungal disease, insect damage, or active pest activity? This dimension scores the absence of those problems.

100 = no disease or pest damage visible. 0 = severe, widespread infestation or infection.

25%
3

Weed Pressure

What percentage of the visible lawn is weeds versus desirable grass? Broadleaf weeds, crabgrass, and sedges all count against this score.

100 = essentially weed-free. 0 = lawn is dominated by weeds with minimal desirable grass.

20%
4

Stress Indicators

Are there visible signs of drought stress, nutrient deficiency, or discoloration? Yellowing, browning, and pale or off-color patches all factor here.

100 = rich, uniform color with no stress signs. 0 = severe stress visible across the lawn.

20%
5

Treatment Urgency

How time-sensitive are the issues identified? A lawn with only routine maintenance needs scores high here. A lawn with an active disease outbreak scores low.

100 = no urgent action needed, routine maintenance only. 0 = requires treatment within days to prevent further damage.

10%
Score interpretation

What your number means

Scores are calibrated to your grass type, climate zone, and current season — a dormant warm-season lawn in January is evaluated differently than the same lawn in July.

0–29

Critical

Significant problems require immediate attention. Consider a professional assessment alongside DIY treatment.

30–49

Significant Stress

Multiple overlapping issues. Address urgent items first before moving to secondary problems.

50–69

Moderate Stress

Visible problems that will worsen if left untreated. Follow the treatment plan this season.

70–84

Healthy

One or two issues worth addressing but nothing urgent. A little attention goes a long way.

85–100

Thriving

Your lawn is in excellent shape. Stay ahead of seasonal timing and maintain your current routine.

What this score is not

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