Too Lazy To Garden
Water

Irrigation & drip planner

Enter each bed and get tubing length, emitter spacing and count, total flow rate, run time to apply an inch of water, and a parts list.

System settings

1 inch/week is the classic veg-garden target.

Time a 5-gal bucket: 5 ÷ minutes = GPM. Typical hose bib is 4–8.

Drip needs 15–30 PSI — a regulator is not optional.

Drip lines
4
every 12"
Tubing needed
42 ft
32 ft in-bed + 10 ft feed
Emitters
44
11 per line
Flow rate
22.0 GPH
0.37 GPM
Application rate
1.10 in/hr
22.0 gal per hour
Run time for 1"
54 min
19.9 gallons
Bed area
32 sq ft
Pre-spaced emitters every 6–12 in — easiest for beds.
Whole-system totals
Total tubing
42 ft
buy 50 ft
Total emitters
44
+10% spares
Total flow
22.0 GPH
0.37 GPM
Supply
300 GPH
5 GPM at the spigot

Total demand fits your supply — everything can run on one zone.

Parts list
  • 1/2" mainline / 1/4" drip tubing50 ft (incl. slack)
  • Emitters (if using punch-in)44 + 10% spares
  • Tee / elbow fittings10
  • End caps / figure-8 closures4
  • 25 PSI pressure regulator1
  • Backflow preventer + 150-mesh filter1 each at the spigot
  • Hose-thread swivel adapters1
  • Landscape staples14
  • Battery hose timer1
Drip rules of thumb

• Keep any single 1/4" line under 30 ft and 1/2" line under 200 ft, or the far end starves.

• Sandy soil: closer emitters (6–9") and shorter, more frequent runs. Clay: wider spacing (12–18") and one long slow run.

• Always install backflow preventer → filter → pressure regulator → tubing, in that order.

• Water early morning; run long enough to wet the full root zone (dig and check the first few times).

• Flush the line ends twice a season and before winter; drain everything before a hard freeze.