Are you watering your MN lawn correctly?

Best watering practices to get the most out of our treatments and your lawn.

By Garrett Anderson

Summer is kicking in and we’ve already had our first strings of 90+ temperatures. It may be nice to get that first sunburn out of the way, but your lawn is probably feeling it as well. Stay with us to find out the best watering practices to get the most out of our treatments and keep your lawn going.

 

What we will cover

Why Water?

Watering your lawn is AS important, if not more, than anything that we do. Aside from proper mowing techniques, watering your lawn when needed is critical to keeping it healthy and green during the heat.

Every year about this time we start getting calls about browning/yellowing lawns. Some years it’s due to heat, some years it may be cool but the rain just isnt there. Not matter what, your lawn needs water to continue looking its best, sometimes a lot, sometimes very minimal

You see, our grass types in MN (Bluegrass, Fescue, and Ryegrass) are not meant to withstand high heat and drought for long periods. Even with tons and tons of water, they will generally slow down or stop growth when we get prolonged periods of high heat. After they slow down, they will begin to show signs of stress. This could be certain areas starting to brown out and look dead. That’s the natural habit of our grasses, they will go dormant (not dead!) during times of heat or drought stress. This is where watering is crucial. It not only keeps the plant cool, but keeps it active and able to fight off stresses.

Remember, the BEST defense against weeds is an  active, thick lawn. When you allow your lawn to go dormant or get badly stressed, You will get more weeds, as there is no competition for nutrients and sunlight from the lawn. 

You will also have a MUCH higher chance of getting crabgrass. Crabgrass needs sunlight and hot temperatures so when you allow your lawn to dry out and thin out, you’re allowing sunlight to hammer your soil, increasing the chance of crabgrass dramatically, even with our pre-emergent. This is the reason you see a lot of curblines that have crabgrass, the heat island effect.

Drought Stress, Heat Stress, and Mower Stress

When your lawn goes dormant it is stressed out to the point where it gives up. All summer stresses are similar, but can be really broken up into 3 categories.

Drought Stress

Unless we’ve had a string of REALLY hot weather, drought stress is usually the first sign of dormancy in a lawn. Generally, this will occur right around this time, when the spring rains are letting up and we have not receive good rain for a week or two at a time. Temperatures make a difference, but many times you can get drought stress even when its only 75-80 degrees.

This is the first sign that the lawn needs some water. Starting stages of drought stress will be that the lawn slowly goes from the good, vivid green we like, to an much duller, almost blue color with some browning. Areas of different types of grass will become much more apparent in both color and growth. This is your indicator to water!!! If no watering is done, it will progress from the blue hue to predominately brown and get browner and browner until it is completely dormant.

 

Heat Stress 

Heat stress and drought stress are almost interchangeable. Heat stress generally occurs much quicker for certain parts of your lawn like sunny areas and areas along pavement. This occurs when we have temperatures above 90 for multiple days, like we did a couple weeks back. This is OFTEN mixed up for fertilizer burns because they look and show up very quickly. Heat stress will usually go from a decent color green, to brown and yellow very quickly, within a few days. Even lawns that have irrigation can get heat stress!! That is why its important to water, even if its not your normal programmed day, when we get these strings of high heat. Watering will help cool the soil which intern cools the plant.

Mower Stress

Mower stress occurs when you mow the lawn during times of stress. This could be mowing brownish areas or mowing a perfectly healthy lawn mid-day when its hottest. It can also be mowing after a few days of high heat, before giving the lawn some water.

The tall tale signs of mower stress are long runs of browning areas roughly the size of your mower tire. Many times this first occurs along pavement, where it is the hottest. When you mow a heat/drought stressed lawn, you will actually break the grass blade, instead of bending it. This is why you get the long runs from your tires tracks.

The best way to combat this is choose your mowing time wisely. Do not mow areas that are showing bad signs of stress and do NOT mow midday when it is hot and very sunny. Lastly, try not to mow your lawn when it is very dry, even if its green. If we’ve had some really hot days, give your lawn some water then mow it the next day.

Water in your Fertilizer!!!!

All fertilizer NEEDS to be watered in after the application.

Let me repeat that. If fertilizer was applied, it NEEDS to be watered in!

A common misconception is that fertilizer starts working as soon as its applied. Wrong! Depending on the type of treatment, liquid vs granular, it needs to be watering into the soil so it can be broken down and taken up by your lawns roots. Granular treatments, quite literally, do nothing until they are watered in. Liquid treatments can be a little better, as some of those nutrients can be absorbed through the leaf blades right away, while the rest will need to be watered in.

What’s worst, is when you do not water in fertilizer, it begins to go through the nitrification process and can be lost to the air through volatilization. Where that fertilizer is sitting plays a big part on what process it goes through. Let me explain.

Fertilizer needs to go through a process before it becomes ready for the plant to take up. The Nitrification process takes the fertilizer and does many different things, breaking it down into many different products. If it is in the soil, many different microbes break it down into different compounds that can then be taken up through the root system. If it is ON TOP of the soil it will volatilize to the air and you will lose more and more of it as time goes on.

IMPORTANT- THIS IS WHY YOU NEED TO WATER THE FERTILIZER IN!!

It kills me to see people not watering in their fertilizer. It is literally sitting on top of your soil, losing its oomf, until it rains or you water. Luckily, depending on the quality of fertilizer, there are things that can help volatilization. We use a special product that keeps the fertilizer from volatilizing. This works REALLY well, however, it still needs to be watered in. These products simply allow for a much longer time frame before you start losing it to the air.

For example- with a lower quality fertilizer, you may lose 25% of your fertilizer within 7 days of the treatment. If it still doesn’t get water, you’ll continue to lose more and more. With a quality fertilizer, like what we use, you may only lose up to 5% or less in that same 7 day period, all way up to 2-3 weeks. It still will do nothing until watered in, but you do not lose nearly as much.

What we recommend is that you water the next morning or day after a treatment, this will allow a bit of time for the weed control to work. If your lawn is in good shape with no or minimal weeds, go ahead and water later that day. Just make sure you are not allowing the grass to stay too wet overnight.

How much? As a general rule, about 15-20 minutes per zone should be enough to get that fertilizer where it needs to be, in the soil.

If there is one thing you take away from this blog, it would be to WATER IN YOUR FERTILZER!

When should you water?

 

If there’s one thing that should be in your head its ALWAYS WATER IN YOUR FERTILIZER!

What about the rest of the growing season? 

This best time to water is ALWAYS in the early morning, from 2-10am. This allows the most water to get to the soil without losing much to the air through evaporation. It is also generally the least windy time of the day which means you’ll get more water on target. Those are the most important reason though…..

Disease! When you water in the AM, your grass will stay much drier throughout the night. When your lawn goes to bed with wet feet, its going to get sick. What I mean is when your lawn stays wet overnight, diseases will become a much higher probability. Diseases thrive in wet, damp areas overnight. Watering in the early morning helps with this.

PM Watering

PM watering is the 2nd best time but far from the best. If done correctly, you can water late afternoon, when the heat is wearing off, and have the lawn dry out before night time. I would say starting around 3-5pm and ending no later than 7pm. Even then, you may be setting your lawn up for fungus and disease. If you have an automated system, set it up for the early morning!

Watering during day

This should be avoided at all costs. When you water during the heat of the day, you are really just cooling your grass. Most of the water that is applied will evaporate. 

There is one covet to watering during the day- If you have planted new grass seed, do everything you can to keep it moist, including watering during the day.

I will say this, watering the lawn at ANY point, is better than not watering at all!

How much should you water?

This is an easy and hard question to answer.

Easy answer- water when your lawn needs it. The best protocol is to wait for your lawn to show beginning signs of stress to water. If it’s turning brown, it is time to water for sure, but a keen eye will be able to tell when the lawn is loosing its oomf. If you notice the color starting to fade and the turf just looks less vigorous, maybe it’s looking almost wilted, its time. The reason this is best is because when you let your lawn dry-out, it promotes its’ root system to dig deeper in search of water.

If you set your watering schedule up based on the same times each week, your usually not allowing it to do this. The result is a shorter root system which may be more disease and stress prone. A tiny bit of drought stress is ok between waterings!

Hard answer- water when your lawn needs it. In MN, most lawns need anywhere from 1-2″ of water a week. More when it’s hot, less when it’s cool, and when it’s snowing outside, you should probably stay away from turning on your system.

Depending on your soil type, these 1-2″ of water should be split 2-4 times throughout the week. If you have a sandier soil, you should water more often for less time. If you have a clay soil, you should water less often for more time. Remember its ALWAYS better to water deep and infrequent then often and light.

Cycle and soak

One of the nicest things new irrigation controllers offer is a cycle and soak option. What this does is allows a zone to only water for a maximum amount of time, lets it soak it, then waters again. Rinse and repeat until the total time is reached for that day/zone. This works GREAT! Many times, when your lawn first gets a lot of water, is it will become saturated in the top layer of soil and not soak in, losing a lot of water to run-off. When you water for 10 minutes, let it soak for 30, then water again for 10, your letting the water soak through the soil much better.

If you have this option, USE IT!!

Smart Watering

In a best case scenario, you only turn your irrigation system on (or hand water) when your lawn needs it. This is the best option but its often much easier to simply set a schedule and forget about it. If possible, try and turn off the schedule, and only water when it needs it. 

This can be even taken a step further- only water the zones that need water. My house has a weird situation. My back lawn rarely needs water, my front and sides need a lot. So I generally only water those areas when they need it. I may turn my back zones on 1-2 times a month, where as my front may be 1-2 times a week.

If you have an irrigation system, there are controllers that are called “Smart Controller”. What they do is take into account the temperature, recent and projected rainfall, evaporation, evapotranspiration, and windspeed. If its hotter, it may water for slightly longer, if winds are high or rain is expected, it may hold off on watering. 

I HIGHLY recommend you switch over to one of these controllers. You still have the option of a traditional schedule, but by setting up a smart schedule, you will pay for your new controller in the first year in water savings. That’s no joke!

I use a controller call the Hunter Pro-HC. Rachio, Rainbird, and many other companies make a smart controller as well. One thing to note, is get one that has WIFI added. It’s very nice being to control system from your phone!

How much is enough?

The best way to know how much to water is to put a pie tin or empty tuna can in numerous spots throughout your lawn. Water for 20 minutes and measure how much water are in the tins. Multiply that by 3 and now you have the amount of water is applied in 1 hour of watering. Depending on the type of soil and how much it needs per week, you now have a solid figure to work off.

For example- Lets say you know 1 hour of watering gets you 1″ of water. You need 1.5″ of water in a specific zone per week. That means you should be watering for a total of 1.5 hours each week. Depending on your soil, this could be 2 times for 45 minutes (using the cycle and soak option hopefully) for a clay soil, or 3 times for 33 minutes each time for a sandier soil. You could even experiment for a month and try doing all 1.5 hours in one time each week.

Please Please PLEASE do NOT water everyday for 10 minutes. This is quite honestly doing almost nothing, except taking money out of your pocket. The least amount of time I’d recommend watering is 20 minutes, unless it is a very shady area.

Watering new seed

If you have planted new seed this spring, now is NOT the time to stop watering. It may look like the new seed is established, but I 100% guarantee you it WILL be the first to die out and not come back during summer.

The #1 concern we hear from people who seeded in the spring is that it came in great but died when it got hot. Most of the time, people stop watering their new seed once it comes in and has been mowed a few times. In most cases, this is about the time when the heat starts to kick in.

Your new grass is extremely susceptible to heat and drought, it has a very shallow root system so it will by the very first thing to dry out. The issue is the root system is so shallow and young that instead of going dormant like most grass, it will just die.

This is precisely why we DO NOT do any seeding as a company in the spring time! 

What can you do? Make sure you continue to water your new seed THE ENTIRE SUMMER!! If it goes dormant, it will most likely not come back. Follow these water steps for new seed-

1- During the first couple weeks, water lightly 1-3 times per day depending on the temperatures. Your goal here is to keep the seedbed moist at all costs. This may be for only 10 minutes per watering session.

2-Once it has began to pop up- continue watering 1-3 times daily for 1 week

3-Cut back on watering to every other day but water for longer- your goal here it to allow the soil surface to slightly dry, not crack, in between waterings. This may be 20-30 minutes total. Continue this type of watering until it has been mowed 2 times

4- After mowing 2 times, start normal watering schedule, pay CLOSE attention to not allow the new grass from stressing out. This may be 2-4 times per week for 20-40 minutes each time. THIS IS THE MOST IMPORTANT STEP THAT MOST PEOPLE DON’T DO. Skipping this step will almost guarantee that the new seed dies out in the summer heat.

Remember the cycle and soak method! You should never be watering to the point it is running off, you may lose your seed and good soil.