Watering Plan & Can Test
Do the can test once. It is the only measurement here that is about your own garden, and everything else follows from it.
BFCBrilliance · bfcbrilliance.com/tools/watering-calculator
The area
- Location
- Date
- Length
- Width
- AREA
- Weekly target (in)
- Sprinkler rate MEASURED (in/hr)
- Sessions per week
- MINUTES PER SESSION
The can test — several cans, one run
| Can position | Minutes run | Depth collected | in/hour | Notes |
|---|---|---|---|---|
Weekly log
| Week | Rain (in) | Still needed | Minutes run | Notes |
|---|---|---|---|---|
The arithmetic and the guidance
- 1 inch over 1 sq ft
- 0.623 gallons
- 1 inch over 1,000 sq ft
- 623 gallons
- 1 cubic foot
- 7.48 gallons
- Most grass wants
- 1-1.5 in per week INCLUDING rain
- Minutes needed
- inches / (in per hour) x 60
- ⚠ Deep and infrequent
- 1-2 sessions a week, not 7
- ⚠ Water
- EARLY MORNING
- ⚠ Runoff?
- cycle-and-soak: run, wait 20-30 min, run again
- Sandy soil
- smaller, more frequent
- Clay soil
- slower, or it runs off
The can test
- Several flat-bottomed cans placed across the area, not just one
- One near the edge and one in the far corner — coverage is rarely even
- Sprinkler run for a measured time (15 or 30 minutes is plenty)
- Depth in each can measured with a ruler
- Inches per hour worked out from the shallowest, not the deepest
- Repeated if you change sprinkler, position or water pressure
- Rainfall measured too — a plain straight-sided container works
Deep and infrequent
One or two long soakings a week send water deep and the roots follow. A little every day keeps only the top inch damp, roots stay shallow, and the lawn becomes dependent on you and fragile in heat. The weekly total matters far more than the schedule — but seven small sessions is not the same as two big ones.
Measure the shallowest can, not the average
Sprinkler coverage is rarely even, and the dry part of the lawn is what you actually notice. Working from the shallowest reading over-waters the middle slightly and keeps the edges alive, which is the right trade. If the spread between cans is large, the fix is sprinkler placement, not run time.