Springtime in the Twin Cities means it’s time to help your lawn recover from a harsh winter and start the new year with healthy growth. Want to make your lawn stand out from all the others on the street? Start on the right foot with these spring lawn care tips for Minneapolis-St.Paul.
Here are some of the best things you can do for your lawn in spring:
- Diagnose and treat problems from winter
- Deal with springtime lawn diseases
- Save overseeding for fall
- Remove excessive thatch buildup
- Apply pre-emergent weed control
- Get to know your soil
- Fertilize after spring growth
- Don’t irrigate until your grass needs it
- Mow high
- Avoid aerating
- Exterminate lawn pests before they get out of hand
- Dust off your lawn care equipment
1. Diagnose and treat problems from winter
Minnesota winters take their toll on your lawn. Frozen soil and heavy snowfall can cause damage that lasts into spring.
Here’s the winter damage you should look for and what you can do about it.
Ice cover damage
What is ice cover damage?
- When spring snowmelt can’t properly drain from your yard, it will thaw and refreeze on top of your grass over and over again throughout late winter and early spring. Damage from the process can kill sections of your lawn.
What should you look for?
- Long strips or irregularly shaped patches of dead grass
- Affected grass will be tan or straw-colored at first, then turn brown
- Clear distinction between damaged and healthy sections of the lawn
How do you treat ice cover damage?
- In this case, the affected grass is already dead. You can improve your lawn’s appearance by resodding or reseeding areas with dead grass.
Snow mold
What is snow mold?
- Gray snow mold and pink snow mold are lawn diseases caused by lawn fungi that grow under the snow during winter. You’ll start seeing snow mold in early spring as the snow cover melts. Its spread will usually slow down or stop completely when the weather gets hotter and drier.
What should you look for?
- Round patches of gray or tan grass that may sometimes appear pale pink or silvery
- Cobweb-like fungus growing on top of the grass
- Tiny brown balls growing on infected blades of grass
How do you treat snow mold?
- Remove thatch from infected areas and gently rake the mold off. Mow the lawn shorter than usual until the fungus stops spreading. Reseed affected spots in your lawn with new grass, and the lawn will eventually go back to normal. Before next year, apply a pre-emergent fungicide to prevent another infection.
De-icing salt injury
What is a de-icing salt injury?
- You know the salt you spread on the driveway and sidewalk in winter? De-icing salt can damage your grass. As with other winter-related damage, you won’t be able to see the effects until spring after the snow cover melts.
What should you look for?
- Dead grass around the sidewalk, driveway, curb, and other places where you applied de-icing salt
- Straw-colored grass that turns dark brown over time
How do you treat de-icing salt damage?
- Apply a soil conditioner with gypsum to the affected areas of your lawn to counteract the salt and help the grass heal
2. Deal with springtime lawn diseases
Notice discolored or wilted sections of grass in your yard and can’t figure out why? You might have a lawn disease on your hands.
Under the right conditions, fungi can thrive in your lawn and cause symptoms like dead or thinning grass. Wet weather supports fungal growth, so spring (after snow melts) is an active time of year for these diseases.
Improper lawn maintenance also creates an ideal environment for diseases to develop and spread. Mowing your lawn to the correct height, watering the right amount, and reducing thatch levels are some of the best ways to prevent lawn diseases.
We’ll go over some of the most common springtime lawn diseases in the Midwest, along with how to get rid of them.
Leaf spot/melting out
What should you look for?
- Purple, red, or brown spots on individual blades of grass
- Thinning turf
- Large irregular patches of dead grass
How do you treat leaf spot/melting out?
- To prevent leaf spot, avoid watering the lawn in the evening, remove excess thatch, and use nitrogen fertilizers sparingly. If you catch leaf spot before patches of the lawn start dying, fungicides can be an effective treatment. Once melting out spreads, you’ll have to reseed the affected sections of grass for them to look normal and healthy again.
Necrotic ring spot
What should you look for?
- Rings of straw-colored or red grass in a “frog-eye” pattern
- Sunken or depressed sections of the lawn
- Black strands of fungus on the grass
How do you treat necrotic ring spot?
- Necrotic ring spot can be difficult to get rid of once it’s established in your lawn. Fungicides can be an effective means of control, but only if you catch the disease before it severely damages your grass. The best way to control necrotic ring spot is to adjust how and when you mow, water, fertilize, and dethatch your lawn.
Rhizoctonia yellow patch
What should you look for?
- Patches of bright yellowish-green grass that gradually turn tan or brown and can spread from 2-3 inches to 2 feet wide
- Possibly red or reddish-purple grass around the edges of infected areas
- Often mistaken for necrotic ring spot, but yellow patch won’t cause the same strands of black fungus as necrotic ring spot
How do you treat Rhizoctonia yellow patch?
- Reduce moisture in your lawn and aerate the soil whenever possible. Managing thatch, adjusting fertilizer, and other proper lawn care practices can also help stop the spread. There are no fungicides that work on yellow patch.
Sclerotinia dollar spot
What should you look for?
- Circular or blotchy patches of yellowish or straw-colored grass
- Light-colored leaf spots with reddish-brown borders on individual blades of grass
- Cobweb-like fungus on infected grass in the mornings
How do you treat Sclerotinia dollar spot?
- Depending on your lawn’s reaction, try watering more or less than usual and fertilizing with less nitrogen to manage the spread of dollar spot. Use fungicide only if the infection is severe and good lawn management practices don’t help.
Powdery mildew
What should you look for?
- White powdery substance covering infected grass
- Yellowing grass
How do you treat powdery mildew?
- Powdery mildew thrives in shade, so pruning or removing trees and shrubs blocking sunlight from the infected area can help. If reducing the amount of shade to the affected area isn’t an option, consider replacing the grass in that spot with mulch or a ground cover plant that isn’t susceptible to powdery mildew.
Stripe smut
What should you look for?
- Thin or patchy grass growth
- Streaks on individual blades of grass that start out yellow-green, then turn gray, and then black
- Blades of grass splitting lengthwise
How do you treat stripe smut?
- Apply nitrogen fertilizer to the infected area in early spring and water deeply early in the day to stimulate healthy new growth. Note: Don’t use nitrogen fertilizer in summer when your cool-season grass is dormant. Core aeration may help stop the disease since it decreases soil dampness. You may also try reseeding with fungicide-treated seeds. If the infection becomes severe, try applying a fungicide that contains benomyl in early spring.
Red thread
What should you look for?
- Bleached or patchy areas of grass
- Infected areas may turn a whitish or pinkish color
- Pink jelly-like or bright red threadlike fungus growing on top of the grass
How do you treat red thread?
- Water the lawn deeply early in the day, collect grass clippings after mowing to reduce thatch, and apply nitrogen fertilizer to reduce damage to your grass caused by red thread. With proper lawn care practices, you likely won’t have to resort to fungicides.
Fairy rings
What should you look for?
- Mushrooms growing in large circles
- Dark green rings in the grass
- Poor grass growth or dead grass inside the rings
How do you treat fairy rings?
- Fairy rings are difficult to remove. You have to dig up the infected area down to a foot deep and remove that section of grass, roots and all. Many homeowners choose to let fairy rings be, as long as they don’t cause too much damage. Reduce damage from fairy ring symptoms by fertilizing the lawn with nitrogen, keeping the soil aerated, and improving soil moisture.
Slime molds
What should you look for?
- White, slimy substance forming on grass that eventually turns to a powdery residue
- Yellowing or weakening grass in infected areas from the fungus blocking sunlight to the grass
How do you treat slime molds?
- Brush slime molds off with a rake or broom. You also could use a high-pressure stream of water from a hose to remove slime mold residue before it causes damage to the grass.
3. Save overseeding for fall
You may be tempted to overseed your lawn in spring so you have a thicker lawn for summer, but that won’t work for lawns in the Minneapolis-St. Paul area. Why? Because the best grass types for Minneapolis lawns are cool-season grasses, which go dormant through summer.
New cool-season grass seeded in spring will have a hard time establishing itself. It will have to compete with warm-season weeds during its peak growing season of late spring and summer. Sensitive, newly seeded cool-season grasses likely won’t survive the drought and heat of summer, either.
The best time to overseed cool-season lawns is in fall, not spring. Here are some of the common Minnesota grasses you should wait to overseed:
- Fine fescue
- Kentucky bluegrass
- Turf-type tall fescue
- Perennial ryegrass
4. Remove excessive thatch buildup
If needed, you should dethatch your yard before applying fertilizers, herbicides, or pesticides. Excessive thatch can block the chemicals and prevent these treatments from working.
What is thatch? Thatch is a naturally occurring layer of dead grass, leaves, and other plant matter that forms between the soil and the grass. The plant matter houses beneficial bacteria that add nutrients to the soil.
How do you know if you need to dethatch? If the thatch in your lawn builds up to more than ¾ inch, it’s time to dethatch. Any layer of thatch thinner than that is fine — even beneficial.
Your yard likely won’t need dethatching every year, especially in spring. As with overseeding, fall is the ideal time to dethatch the cool-season grasses of the Twin Cities area. You should only dethatch in spring if you absolutely must.
5. Apply pre-emergent weed control
Apply pre-emergent herbicides in spring to prevent an infestation of summer weeds later. Once the risk of a hard frost has passed and the soil reaches at least 55 degrees, it’s time for pre-emergent herbicides. In the Minneapolis-St. Paul region, this is generally mid-April.
About 8-10 weeks after the first application, you may need to apply the same herbicide again for weeds that germinate later in the season.
Here are just a few of Minnesota’s bothersome summer annual weeds you won’t have to deal with if you use pre-emergent herbicides in spring:
- Barnyardgrass
- Crabgrass
- Foxtail
- Fall panicum
- Wild proso millet
- Pigweeds
- Ragweeds
- Cocklebur
- Lambsquarters
- Velvetleaf
- Bindweeds
- Yellow nutsedge
Fortunately for you, there aren’t many cool-season weeds actively growing in spring in Minnesota. That means you don’t need to worry about applying post-emergent herbicides at this time of the year.
6. Get to know your soil
Before fertilizing, find out which nutrients your soil lacks and which amendments it needs. Your soil might be too acidic or too alkaline, and you can fix it. Start with a soil test from the University of Minnesota’s Soil Testing Laboratory.
The results of your test will tell you what you should add to the soil for the healthiest grass growth. Common amendments your soil might need include lime, magnesium, and phosphorus. There’s no way to know exactly what your soil needs until you get it tested.
Add any soil amendments at least four weeks before fertilizing the lawn for the first time.
In addition to your soil pH and nutrient levels, you should get familiar with your soil’s texture. Knowing whether your soil contains more sand, loam, or clay will give you an idea of how well it retains water and nutrients. Then you can figure out the best way to fertilize and water your lawn.
The most common type of soil in the Twin Cities region is Lester, the state soil. This soil is typically loamy and well-draining, which makes it great for growing many types of grass and plants.
7. Fertilize after spring growth
The best time of year to fertilize a lawn in Minneapolis is usually May or June.
According to the University of Nebraska-Lincoln’s maintenance calendar for the Midwest’s cool-season grasses, you should fertilize your lawn when growth slows after the big growth surge in mid-spring.
Apply approximately ½ to ¾ pound of nitrogen per 1,000 square feet of lawn. For the best results, use a slow-release fertilizer or one that contains half slow-release and half fast-release fertilizer. Avoid straight fast-release fertilizers because they can burn your grass and force it to grow too much too quickly.
Use a spreader to coat all areas of the lawn evenly with fertilizer. When you spread fertilizer manually, you risk leaving streaks in the lawn or creating patchy, unattractive growth.
8. Don’t irrigate until your grass needs it
From the beginning of the year until early May, your grass has enough water stored in its roots to get by on its own. That’s why you shouldn’t start watering the lawn until late spring. Otherwise, you risk making the soil too moist, which can invite lawn diseases and pest infestations.
The best time to start watering your lawn is when your grass shows signs of needing moisture, so there’s no set schedule that works for everyone.
Look out for these signs that your lawn is ready for spring watering:
- Grass begins to wilt
- Color fades from bright green to dull gray
- You can see footprints in the grass when you walk through it
Your Minneapolis-St. Paul area lawn will typically exhibit these signs in late May or early June.
When you decide it’s time to start watering regularly, you should water no more than an inch per week. Keep in mind that cool-season grasses are more susceptible to overwatering than underwatering in spring.
9. Mow high
Keep cool-season grasses relatively high in spring and summer. The ideal lawn height is around 3 inches through the hottest part of the year.
Taller grass is good because it crowds out the weeds that will try to grow in your lawn at this time of year. Plus, grass that’s allowed to grow tall will develop deeper roots, which will make the lawn more drought-tolerant for late spring and summer.
Because you want the grass to grow higher, you’ll have to wait longer to start mowing in spring. Let the lawn grow to 3 or 4 inches tall before you mow for the first time.
Whenever you start mowing, here are the recommended cutting heights for the most common grass types in Minnesota.
| Grass type | Height for early spring | Height for late spring/summer |
| Fine fescue | 1 – 2 ½ inches | 2 – 3 inches |
| Kentucky bluegrass | 1 ½ – 2 ½ inches | 2 – 3 ½ inches |
| Turf-type tall fescue | 2 – 3 ½ inches | 3 – 4 inches |
| Perennial ryegrass | 1 ½ – 2 ½ inches | 2 ½ – 3 ½ inches |
Follow these rules of thumb for the healthiest cut possible:
- Never mow wet or damp grass
- Leave lawn clippings in the yard, but don’t let them buildup more than ¾-inch thick
- Never cut more than ⅓ the height of the grass at once
10. Avoid aerating
Aerating in spring is a bad idea for any lawn, but especially for Minnesota’s cool-season grasses.
When you aerate, you poke holes in compacted soil to create better circulation and give grassroots easier access to water and soil nutrients. Those holes also give summer annual weeds a convenient place to germinate and grow.
Weeds are never good, but they’re even worse than usual for cool-season grasses, which go dormant in summer. While the grass is dormant, it can’t compete with the weeds for water, sunlight, and nutrients.
However, if spring has sprung but your grass won’t grow because the soil is too compacted, you may have to aerate despite the drawbacks.
If you need to aerate in spring, figuring out when to aerate your lawn can be tricky. You want to wait until late spring (after most weeds have germinated) if possible, but you don’t want to wait until it’s too hot out since aerating in extreme heat can dry out the soil.
So avoid aerating in spring unless it’s an emergency.
11. Exterminate lawn pests before they get out of hand
In spring, lawn pests reproduce and grow. Get rid of them during this stage before they develop into adults that damage your lawn much more than grubs do.
Some common lawn pests that come out in spring in the Minneapolis-St. Paul area include:
- Ants
- Bluegrass billbugs
- Japanese beetles
Of these, Japanese beetles will probably be your biggest problem. Neem oil and selective anti-beetle products that contain the bacteria Bacillus thuringiensis galleriae are two options for getting rid of Japanese beetles without harming beneficial insects such as ladybugs and bees.
Proper lawn care management is the best way to prevent pests. A healthy, correctly watered, and fertilized lawn with minimal thatch will not appeal to most harmful insects as a place to live.
Use pesticides as a last resort only, since they usually kill the good bugs along with the bad. Selective pesticides, like the ones for beetles, get rid of your targeted pest without harming other organisms.
12. Dust off your lawn care equipment
Before the weather warms up and lawn care becomes a part of your weekly routine, prepare your tools for heavy use. Your lawn mower, weed whacker, hedge trimmer, and other power tools have been dormant all through winter, and they need a little help to get back into the swing of things in spring.
Here are some important tasks you should get done in spring:
- Load new line into your weed eater
- Sharpen lawn mower blades
- For gas-powered lawn mowers: Replace the spark plug, change the filter, and change the oil
- For gas-powered tools: Make sure you have plenty of gas to get you through summer
- For battery-powered tools: Check that the batteries still hold a charge
Taking care of these things in spring will make your life easier later when you need to use your tools frequently.
Reap the benefits of spring lawn care year-round
Give your Minneapolis lawn a strong start in spring, and it will have a better shot at staying healthy through the rest of the year. On the other hand, if you neglect spring lawn care, you can expect your grass to have a lot more problems later on.
And when the leaves start to turn, we’ve got you covered with your Fall Lawn Care Checklist. Yes, one of the to-do items is to clean up those leaves.
Proper spring lawn care — and summer and fall lawn care, too — takes a lot of time and attention, which you may not have to spare. Instead of getting your hands dirty, hire a Minneapolis lawn care pro to take care of your lawn for you. Then you can sit back, relax, and still have a beautiful lawn year-round.
Main Photo Credit: Chris Sorge | Flickr | CC BY-SA 2.0
