When to water your garden, and when not to

Time of day

Early morning, 5 to 9am, is best. Cool air means less evaporation. Leaves dry off before evening, which means less fungal disease. Plants take up water all day to grow.

Late afternoon, 5 to 7pm, is second best. Water at soil level. Don't soak the leaves.

Never water in the heat of the day. Most of it evaporates before reaching roots. What's left acts as a magnifying glass on leaves.

How often, honestly

Deep, infrequent watering grows deeper roots than shallow daily watering. Most gardens get watered too often.

• Lawn: 25mm once a week beats 5mm every day.
• Veggie patch: 25 to 40mm deep, twice a week in summer.
• Established trees and shrubs: Often nothing in spring and autumn, deep soak in long dry spells.
• Pots: Daily in summer. Pots dry out fast.

The finger test

Push your finger 5cm into the soil. If it's dry, water. If it's cool and damp, wait. More reliable than any schedule.

Skip watering when

• It's rained more than 5mm in the last 24 hours
• More than 10mm of rain is forecast tonight
• The soil is still soaked from the previous watering
• The plants are dormant (most natives in summer, deciduous trees in winter)

Drip irrigation pays for itself

A $40 timer and $30 of drip line waters the veggie patch at 5am while you sleep. Saves at least half the water that sprinklers waste. Plants thrive on the steady moisture.

Check today

Open Window Today's "Water the garden" card factors in the last 24 hours of rainfall, today's temperature, and the forecast. It tells you yes, no, or wait, in one second.

Why early morning beats every other time

The best time to water a garden is early morning, before the heat of the day. Watering then gives plants a full reservoir to draw on as temperatures climb, and because the sun is still low, far less is lost to evaporation than a midday soak. Crucially, the foliage has all day to dry off, which matters because leaves that stay wet overnight are an open invitation to fungal diseases like mildew and black spot. Morning watering hits the sweet spot of low evaporation and dry leaves by nightfall.

Why midday and evening watering waste water or invite disease

Watering in the heat of midday is the least efficient choice, because a large share evaporates before it reaches the roots, and droplets on leaves can act like tiny lenses in strong sun. Evening watering is better for evaporation, but it leaves foliage and soil damp through the night, which is exactly the cool, moist condition fungal disease and slugs thrive in. If morning is genuinely impossible, early evening is the next best option, but aim water at the soil and keep it off the leaves.

Watering deeply, and skipping it when it rains

How you water matters as much as when. A deep, thorough soak two or three times a week encourages roots to grow downward in search of moisture, building drought-resilient plants. A light daily sprinkle does the opposite, keeping roots shallow and needy. Push a finger into the soil before watering; if it is still damp a few centimetres down, the garden does not need it yet. And the obvious one people still get wrong: check the forecast and skip watering when meaningful rain is coming, because overwatering drowns roots and wastes water just as surely as drought starves them.

Frequently asked questions

What is the best time of day to water plants?

Early morning. It minimises evaporation, fills the plants before the day's heat, and lets foliage dry by nightfall, which prevents fungal disease. Early evening is an acceptable second choice if you water the soil, not the leaves.

Is it bad to water plants in the evening?

It can be. Evening watering leaves leaves and soil damp overnight, encouraging fungal disease and slugs. If you must water in the evening, aim at the base of the plant and keep the foliage dry.

How often should I water my garden?

A deep soak two or three times a week beats a light daily sprinkle, because it drives roots deeper and builds drought resistance. Check the soil first and skip watering when rain is on the way.

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