The Best Time of Day to Water Your Garden (and Why it Matters)

The science behind watering timing

There’s often more to watering than you think. Temperature, sunlight and evaporation all influence how quickly water is absorbed by your plants and how much they benefit from a drink. 

When it comes to plants, moisture isn’t just lost through soil. It’s also lost as water vapour through through pores on their leaves via a process called transpiration. Evaporation rates typically increase during the summer months with stronger sunrays and longer daylight hours. With this in mind, you might need to adjust your watering schedule depending on the time of year. 

Morning vs. afternoon vs. evening

What’s better for watering: morning, noon or night? Let’s breakdown what happens when you water your plants at different times of the day.

Morning

Watering in the morning is typically considered the best time of day to give your plants a drink, especially over those hot summer months. The temperature is typically cooler in the morning, meaning there’s less evaporation, giving your plants plenty of time to absorb the water.

As the sun rises and the temperature heats up, the remaining moisture evaporates, drying out the soil and leaves, helping to reduce the risk of fungal diseases and pests. 

Afternoon

At mid-afternoon when the sun is high, there are usually higher evaporation rates. Not only is watering your plants at this time of day less efficient, it can also lead to possible heat stress. In some cases, the water can evaporate before it has the chance to reach your plants roots, leaving them worse off than when you started. 

If you don’t get a chance to water your plants in the morning, the next best time of day is late afternoon, when the temperature starts to drop and evaporation rates start to slow.

Evening

After a long, hot day in the sun, it can be tempting to want to give your plants a good soak if they’re looking a little wilted. And while there’s nothing wrong with a late afternoon shower as the heat starts to ease, leaving your watering until later in the evening can actually cause more harm than good. 

Without enough time to dry off, water can sit on the leaves overnight, leading to mildew and rot. Not to mention, cooler overnight temperatures reduce natural evaporation, which can increase the risk of disease.

If you have no choice but to water your plants in the evening, give it a little water, but not as much as you would in the morning.

Special cases and exceptions

It’s worth noting that these general watering rules often change depending on the circumstances. Whether you’re dealing with heatwave conditions, container gardens or drought-tolerant plants, here are a few exceptions to the rules.

Watering during heatwaves

Heatwave conditions can really take their toll on plants. If your plants are wilted and the soil is dry after you’ve dug down around 5cms, then it’s important to give them a drink to help them regain some hydration. Focus on watering the base of your plants so the roots can absorb the moisture and nutrients. 

Container gardens vs in-ground plants

Plants in containers, like pots and planters, tend to dry out much faster than plants in the ground. Some materials, like terracotta, are porous, allowing for rapid water evaporation. Not to mention pots tend to absorb heat, stressing plant roots and drying the soil. With this in mind, you’ll generally need to water container plants more frequently than in-ground plants. 

Shaded gardens or drought-tolerant plants

Different rules apply again to shaded gardens and drought-tolerant plants. These types of plants generally need less frequent watering. Depending on their placement or the type of plant itself, deep watering around the base of the plant once a week can be enough to give the roots the moisture they need. 

Smart watering do’s and don’ts

Want to keep your garden thriving while saving water? Here’s a quick guide to the watering habits that help the ones that hinder.

The do’s: Watering done right

• Use weeper or soaker hose: These deliver water directly to the roots, reducing evaporation and runoff.

• Water deeply, but less often: Encourages strong, deep root systems and reduces the need for frequent watering.

• Check soil before watering: Use the finger test—if it’s dry 5cm down, it’s time to water.

• Add mulch to garden beds: Mulch helps soil retain moisture and regulate temperature.

The don’ts: Common watering mistakes

• Don’t water at night: This can promote fungal growth due to cooler, damp conditions.

• Don’t water lightly and often: It promotes shallow roots, making plants less resilient.

• Don’t water during the heat of the day: Much of the water will evaporate before reaching the roots.

• Don’t ignore signs of stress: Wilted leaves or dry soil are a sign your plants might need attention.

Optimise your watering schedule with Nylex

While morning is generally the best time of day to water your plants, its important to adjust your watering schedule to suit your garden. That said, it also helps to have the right watering tools on hand to help your garden thrive