Keeping your lawn healthy through the winter months can be a challenge, especially if you live in an area with harsh winters. Grass goes dormant in winter, meaning it stops actively growing and turns brown. While dormant grass is not dead, extended freezing temperatures can damage and kill turfgrass. There are several steps you can take in late fall and throughout the winter to help your grass survive and stay greener for spring.
Why does grass turn brown and appear dead in winter?
There are a few key reasons why grass loses its green color and may appear dead during winter:
- Lack of sunlight – The short daylight hours and weaker intensity of the sun in winter limits photosynthesis, the process grass uses to produce nutrients and grow. This causes grass to stop actively growing.
- Freezing temperatures – Prolonged freezing temperatures can damage and kill grass plants. The crown, roots and rhizomes are most vulnerable.
- Dessication – Cold, dry winter winds draw moisture out of dormant grass, which can desiccate and damage the plants.
- Lack of nutrients – Grass depends on nutrients from fertilizer, compost and grass clippings. Little fresh organic matter is generated in winter.
While dormant grass appears brown and lifeless, the plants are still alive. Avoid walking on frozen grass or letting children and pets play rough games to limit damage. Proper care will help your lawn survive winter stress and green up quickly in spring.
Prepare your lawn in fall
The steps you take in fall before winter arrives are crucial for maintaining grass health. Here are tips for fall lawn preparation:
- Keep mowing regularly – Continue mowing into late fall, gradually raising the height to 3-3.5 inches for the last mowing. This allows grass to stockpile carbohydrates.
- Remove leaves – Rake up fallen leaves, as smothering layers of leaves can mat down and kill grass over winter.
- Aerate the soil – Core aeration improves drainage and allows nutrients, air and water to better reach grass roots.
- Apply fertilizer – Fertilizing in fall helps grass recover nutrients and build food reserves for winter survival.
- Reseed bare spots – Fall is the best time for overseeding and repairing thin, bare areas in your lawn before winter.
- Treat weeds – Spot treat persistent weeds in fall to prevent them robbing nutrients from grass plants.
Proper mowing, fertilization and weed management in fall ensure your lawn enters winter healthy, with the energy stores it needs to survive.
Continue watering into fall
It’s important to keep watering your lawn into early fall until the grass goes fully dormant. Follow these fall watering tips:
- Water deeply 1-2 times per week until ground freezes.
- Water in morning so grass blades dry before nightfall.
- Adjust sprinklers to wet soil 4-6 inches deep.
- Watch for irrigation water freezing on grass blades.
- Gradually reduce frequency as growth slows.
Supplement rainfall with manual watering as needed until regular frosts begin. This encourages deeper root growth and stockpiling of carbohydrates in crowns.
Continue mowing until growth stops
It’s important to continue mowing into late fall, until grass growth stops completely. Here are fall mowing tips:
- Make final mowing at 3-3.5 inch height.
- Use a mulching mower to recycle nutrients back into lawn.
- Change mowing direction each time to avoid ruts.
- Remove no more than 1/3 grass blade per mowing.
- Make sure mower blades are sharp for clean cuts.
Mowing higher helps grass conserve energy while still keeping the lawn tidy. Stop mowing once frosts end grass growth, usually late fall.
Fertilize in fall
Fertilizing in fall can help strengthen grass before winter. Ideal timing is 1-2 months before first expected frost. Options include:
- Quick release fertilizers – Apply 1 lb nitrogen per 1,000 sq ft in early fall.
- Slow release fertilizers – Apply in late fall at manufacturer’s recommended rate.
- Organic options – Compost, compost tea, milorganite, corn gluten meal.
- Starter fertilizer – Use at time of overseeding bare spots.
A soil test can help determine if your lawn needs any adjustments to pH or nutrients before winter. Fertilizing too late in fall risks frost damage to tender new growth.
Overseed bare spots in fall
Fall is the ideal time to repair thin, patchy areas of your lawn. Here are tips for fall overseeding:
- Mow, dethatch and aerate lawn in early fall before overseeding.
- Select grass seed mix suitable for sun/shade exposure.
- Spread seed according to package instructions.
- Gently rake seed into soil surface.
- Water newly seeded areas daily until sprouted.
- Cover with straw if laying new grass seed sod.
Overseeding ensures bare areas have adequate grass coverage before extreme winter weather arrives. New grass needs 6-8 weeks before first frost to establish.
Control fall weeds
Prevent weeds from stealing water and nutrients from desired grass during winter dormancy. Fall weed control options include:
- Apply preemergent weed control in early fall.
- Manually dig out pesky perennial weeds.
- Spot treat broadleaf weeds with selective herbicides.
- Overseed to crowd out annual weeds.
- Reseed bare spots prone to weed infestation.
Controlling fall weeds prevents them from getting a foothold and infesting lawns the following spring. But avoid weed killers late in fall when grass growth has slowed.
Remove fallen leaves
Rake up and remove fallen leaves from the lawn in fall. Leaves left on grass can:
- Smother and block sunlight from grass blades.
- Provide cover for pests like rodents and insects.
- Promote disease and mold growth.
- Add a deep mat that’s hard to remove come spring.
For smaller lawns, use a leaf blower to gather leaves onto beds or tarps for composting. Removing leaves helps sunlight, air and water reach dormant grass plants.
Aerate compacted soil
Lawns with compacted clay soil benefit from core aeration in fall. This process:
- Loosens heavily trafficked, compacted soil.
- Creates channels for air, water and nutrients.
- Promotes deeper grass roots.
- Improves drainage before winter rains.
- Can be paired with overseeding.
Consider renting an aerator or hiring a professional for larger yards. Target areas near walkways, under trees and along the perimeter.
Start mowing again in early spring
Here are tips for spring lawn revival:
- Begin mowing again when new growth reaches 3-4 inches tall.
- Set mower blades to lowest setting for the first mowing.
- Remove any stray leaves still smothering grass plants.
- Fill in bare spots with new grass seed.
- Begin watering if spring is dry, avoiding runoff.
Resuming proper mowing height and fertilization in spring will help grass recover from winter. Overseed thin areas before summer weather arrives.
Install a winter lawn blanket
Covering grass with a breathable winter lawn blanket can further protect it from harsh winter weather. Benefits include:
- Insulates grass crowns from extreme cold.
- Reduces desiccation and drying winds.
- Protects against ice sheeting that blocks sunlight.
- Prevents smothering by heavy snow.
- Promotes faster spring green-up.
Use stakes or turf staples to keep the blanket in place. Remove in early spring once temperatures rise and grass begins growing again.
Apply fall and winter fertilizer
Continue fertilizing into the winter months to nourish dormant grass. Options include:
- Slow-release fertilizer – Apply late fall for gradual winter nutrient release.
- Sulfur or iron – Promotes green color on dormant grass plants.
- Potassium – Aids drought and cold tolerance over winter.
- Nitrogen – Very light feeding in early winter only if needed.
Always follow label directions. Fertilizing too heavily during cold periods risks burning grass or leaching nutrients. Target fertilizer on visible thin or discolored areas.
Adjust mower height for winter grass
Here are winter mowing height tips:
- Raise mower height another 0.5-1 inch for winter.
- Higher height insulates crowns from cold.
- Continues photosynthesis in winter sunlight.
- Reduce mowing frequency as growth slows.
- Sharpen mower blades for clean cuts.
Discontinue mowing once ground freezes solid. Let grass go dormant until spring growth resumes. Never mow frosted grass blades.
Install lawn heating cables
Electric or hydronic heating cables can further protect valuable grass like sports fields and golf greens. Benefits include:
- Maintain surface temperature above freezing.
- Allow for continual winter play and use.
- Reduce frost heaving and ice cover damage.
- Promote faster spring green-up.
- Reduce need for frost covers or tarps.
Heating cable installation requires professional expertise. Improper layout risks burning or shocking grass plants. Systems require special thermostats and monitoring.
Use extra winter lawn protection
Harsher winter climates may require additional protection measures beyond fertilizer and mowing. Options include:
- Anti-desiccant spray – Forms protective film reducing moisture loss.
- Dormant grass paint or dye – Non-toxic tints provide color on dormant grass.
- Snow mold fungicide – Prevents pink and gray mold in snow cover.
- Extra potassium fertilization – Boosts winter hardiness tolerance.
Use any winter protective products at manufacturer recommended rates to avoid potential grass injury or toxicity.
Allow animals and kids to enjoy winter grass
While dormant, grass remains vulnerable to excessive foot traffic and playing. Ideas include:
- Rotate play to different yard areas.
- Restrict pet access to let grass rest.
- Walk pets on pavement or paths.
- Ban horseback riding from grass pastures.
- Close sections of sports fields to alternate use.
Allowing dormant grass a complete winter rest helps ensure it recharges properly for spring. Temporary fencing can protect overused areas.
Check for snow mold fungal disease
Areas under prolonged snow can develop gray snow mold or pink snow mold fungal disease. Look for:
- Circular patches of matted gray grass.
- Fuzzy cotton-like gray fungal growth.
- Bright pink cobweb-like fungal growth.
- Grass remnants easily peel away.
- Most severe in shady, wet sites.
Improve drainage and air circulation to prevent reoccurrence. Rake matted grass and reseed any dead spots come spring.
Conclusion
Caring for your lawn properly in fall and winter is crucial for a healthy, lush lawn come spring. Prepare grass for winter by fertilizing, aerating, overseeding and mowing into fall. Remove leaves promptly and continue watering while grass is still active. Once growth stops, allow grass to go dormant until spring. Install winter lawn blankets, heating cables or temporary fencing if needed in regions with harsh winters. Avoid excessive foot traffic on frozen, dormant grass. Renew fertilization, mowing and weed control when grass resumes growth in spring.