This is the first in a Q&A blog series on healthy organic turf. If you have a question for Good Sweet Earth's lawn guy, Steve, shoot him an email at steve@GoodSweetEarth.com, and include "Ask the Lawn Guy" in the subject line.
So the question of "How much should I water?" is a frequent one, which is why I've decided it tackle this one first in our "Ask the Organic Lawn Guy" series.
And here's a simple answer: Water as often as you'd like, to keep your turf as green as you'd like, but make sure you water for at least 30 minutes at a time (ideally 45-60). Read on for a more-nuanced answer.
First, we need to talk about turf in Michigan. We're in what's called a "cool-weather turf zone." That means our turf grows when it's cool, and it goes dormant when it's hot and when it freezes.
And contrary to popular belief, grass shouldn't be bright green in the middle of summer, and you probably aren't going to be mowing it twice a week either. Michigan turf grows and greens in the spring and the fall. Then during the summer and winter, it gets brown and stops growing while it stores up carbohydrates for the next growing season.
So, all that brown grass you see in the summer? It ain't dead. It's sleeping. If you don't mind having brown, crispy grass during the months of July and August, letting it sleep is probably the best thing you can do for your lawn. It'll have much more vigor and density in the fall. That being said, turf shouldn't go for more than three weeks (two in especially hot conditions) without water. So even if you go the dormancy route with your turf, you should still put the sprinklers on every two to three weeks (if there's been no rain). And when you do put the sprinkler on, let it go for about 45-60 minutes per zone. This will allow the water to go deeper into the ground, which will force the roots to grow deeper as well. This will give you stronger and more drought-resistant turf.
But what if you don't want brown crispy grass all summer? What if you like to have some soft green turf to play on and admire? Then my advice to you is to let it get as brown as you're comfortable with, and then put the sprinklers on for 45-60 minutes. For some people, this might mean watering twice or three times a week. For others, it might mean once every 10 days. I don't have a hard and fast rule for how often you should water. Just do it when you think your lawn's getting too brown for your own comfort. If you're able to go 15 days between waterings (and let the grass go into a nice deep dormancy), great! If the thought of crispy turf makes you feel a little uneasy, go as many days as you can without watering, and then let the sprinklers fly.
The only hard and fast rule I have is to water for at minimum 30 minutes, but ideally 45-60, depending on how your soil can handle that amount of water (you don't want puddling). The one thing you don't want to do is a 10-minute watering. This will mean the water never goes very deep into your soil, and neither does your turf's root zone. And that's bad news.
I've talked to too many customers who water their lawn every morning, seven days a week, all summer long, for 5-15 minutes a day. This is not effective for healthy turf. Watering at mid-day or in the evening is also bad. Why? When you water at mid-day, you lose a lot of moisture to evaporation. And watering at night can create a breeding ground for fungus on your grass. Mornings are the best time of day to sprinkle.
Now, I have to mention that there's a real technical answer that turf professionals like to give when asked how much to water a lawn, and it includes the number of inches of water you should be applying, and then putting out coffee cans in your yard while you sprinkle in order to measure the amount of water, etc. But most of us aren't managing a golf course. If you go with what feels comfortable for your lawn, watch out for over-watering (puddles), avoid short watering periods, and avoid mid-day/evening waterings, you'll be fine.
So to sum up: In the spring and fall, you can probably rely on rain to do all the watering your lawn needs, but if you do turn the sprinklers on, water deeply (at least 30 minutes). In the summer, go as long as you're comfortable going. If you don't mind grass that's a little brown, letting your turf go dormant is ideal for it's long-term health. Otherwise, turn the sprinklers on for about 45 minutes in the morning whenever you see your turf getting too brown for your own comfort.
Steve & Corey Veldheer are organic yard & garden specialists in west Michigan.