A lot of people get up early to water their lawn, and we’ve recommended that before. But for the homeowner concerned about sprinkling too much water, waking up to grass covered in morning dew can give pause. Over-watering can create damp conditions that are ideal for disease, fungi, and insects, so you’ll want to avoid it. But does dew have an impact on how much moisture your grass is getting?
What Is Morning Dew?
The little droplets you might wake up to during the summer are an after effect of your lawn radiating its heat. The moisture in the air condenses faster than it can evaporate, becoming too saturated and creating water droplets. When the temperature and humidity no longer allow the air to hold water, the air has reached what is called the dew point. When the air cools to the dew point through contact with a lawn that is colder than the air, water will condense and form droplets on the grass.
These droplets don’t occur every night. The soil has to cool in the right atmosphere, which includes clear skies, calm conditions with lighter breezes, higher moisture in the soil, and a lower dew point during the night. But these are the conditions you’ll find often in an Ontario summer, making dew a common sight in warmer months.
How Does Dew Affect Your Lawn?
So we know that the cooling of warm, moist soil during a calm, clear night will cause condensation near the ground. But what impact does this have on your lawn, especially if you’ve taken to watering in the morning? When you think about how much water you need to keep your grass green and healthy, you’ll see that this mild condensation is just a drop in the bucket.
Typically, your lawn needs an inch of water per week, and to give it this much water, you need to water deeply two or three times a week. This creates a deeper root system and strong, healthy grass. Even in humid locations, the formation of these droplets is a sprinkling, and it evaporates quite quickly as the sun rises. Some plants have evolved to utilize what little water they can get, but your average grass won’t see much hydration from the dewy conditions
Dew has an impact in certain areas and in other times of the season. Many landscapes that need constant manicuring, like golf courses, benefit from removing it before the grass is mowed. It can also be a sufficient source of water for plants that have shallow roots or have adapted to a landscape that does not provide a lot of water. In the colder months, these droplets can freeze to become frost, and this can hurt crops.
All this means it’s safe to say that for average residential lawn care during the summer, the dew forming will not have a huge impact on grass. Dew or not, you can still water the lawn!