Garden & outdoor

How much irrigation pipe and drippers do you need for your garden?

Liters per week and per watering day for your vegetable garden — plus drip line length estimate.

Quick answer

Vegetable gardens in summer peak need roughly 25–40 liters per m² per week depending on crop and mulch — a 20 m² plot at 35 L/m² wants 700 L per week. Split across 3 watering days that is ~233 L per session — two hours with a 100 L/hour drip zone, not a quick sprinkle.

Advanced settings

Water per week

700 L

Liters per watering day
233 L
Drip tube length (estimate)
67 m

Summer peak estimates in liters per m² per week — adjust down in spring/autumn or with mulch. Drip length ≈ area ÷ row spacing when lines run parallel across the bed. A hose timer prevents holiday dry-outs.

How it works

Formula: weekly L = area × L/m²/week; per session = weekly ÷ watering days. Drip tube length ≈ area ÷ row spacing when parallel lines cover the bed (0.3 m spacing is typical). A hose timer on the tap beats guessing while you are on holiday.

Kit shopping after you know metres and litres: a drip irrigation kit garden matched to your row count, soaker hose garden for long beds if you skip emitters, and a watering can 10 liter for seedlings the drip lines miss. Run the timer on early-morning slots — less evaporation than midday, and foliage dries before evening.

Water deep and rarely, not a little every day: shallow watering keeps the roots at the surface, and the first hot week finds a plant that cannot look after itself. Early morning beats evening — leaves that stay wet overnight invite mildew. And drip line under mulch loses far less than the same line in the open: the calculation above assumes the water reaches the soil, not the air.

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Frequently asked questions

How often should I water the vegetable garden?+

In hot dry weeks: 3–4 deep sessions beat daily sprinkles. Seedlings need more frequent light water; established tomatoes and squash prefer fewer, deeper irrigations. Mulch cuts weekly needs by 20–30%.

Drip irrigation vs hose watering?+

Drip puts water at the roots with less evaporation — better for vegetables and water bills. Overhead sprinklers are fine for lawns but wet foliage on tomatoes invites disease. Size drip length with this tool, then buy a kit with matching flow.

How many liters for a 10 m² raised bed?+

At summer vegetable rate (35 L/m²/week): 350 L weekly. On a 4-day schedule → ~88 L per session. Raised beds drain faster — check soil moisture with a finger; calculators give planning numbers, not rain replacement.

Can I use rainwater for the calculated volume?+

Yes — a 1,000 L IBC tank covers about 1.4 weeks for a 20 m² veg plot at peak summer need. Size collection area separately; this tool tells you demand, not supply.

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