Quick answers
Dead patches of grass will often grow back on their own with time and proper lawn care. The key is identifying the cause and addressing it. Common causes include pet urine damage, fungal disease, insect infestation, and lack of water. Fix the underlying problem first. Then, you can encourage regrowth by watering, aerating, overseeding, and fertilizing. With persistence and care, the grass can fill back in.
What causes dead patches of grass?
There are several common causes of dead patches of grass:
Pet urine
Dog or cat urine contains high levels of nitrogen which can burn and kill grass when concentrated in one area. The dead patches often have defined edges.
Fungal disease
Fungal diseases like brown patch and dollar spot cause irregular dead patches that can expand. High humidity and dense shade encourage fungal growth.
Insect damage
Grubs, chinch bugs, and other lawn pests can chew through grass roots and blades, causing dieback. Damaged areas may feel spongy underfoot.
Lack of water
Insufficient irrigation during hot, dry periods can desiccate and kill grass. Drought stress leads to browning and bare areas.
Poor drainage
Excess moisture prevents roots from getting oxygen. Low spots and compacted soil often contribute to poor drainage. Puddling and soggy areas turn brown.
Too much shade
Dense tree shade blocks sunlight needed for photosynthesis and growth. Grass thins and dies back over time in deep shade.
Excessive foot traffic
High amounts of foot traffic, especially during soggy conditions, can compact the soil and crush grass plants. Well-worn paths are prone to die out.
Low soil fertility
Lack of nitrogen, phosphorus, and potassium leads to poor grass growth and dieback. Nutrient deficiency shows as overall discoloration.
Burying grass plants
Adding too much topsoil at once can smother existing grass. Newly seeded areas may also get buried by erosion.
Will the dead grass grow back?
In many cases, dead grass will gradually fill back in over time. The key is correcting the underlying cause of the dieback. Then, proper lawn care and maintenance will encourage the surrounding healthy grass to spread and recolonize bare patches.
However, extensive damage or a recurring issue like heavy shade may prevent full recovery. And some causes like pet urine damage leave behind salts in the soil that inhibit regrowth. Reseeding is necessary if the original grass cannot spread into damaged areas.
Here are some tips for encouraging dead patches to fill back in:
Remove the cause
Eliminate the source of the problem first. For fungal issues, apply appropriate fungicide. For grubs and chinch bugs, use insecticidal treatment. Fix irrigation issues or improve drainage as needed.
Water thoroughly
Water dead areas deeply to encourage grass roots to grow laterally into the bare soil. But avoid overwatering the overall lawn.
Aerate compacted soil
Use a core aerator to punch holes in hardened soil. This allows water, air, and nutrients to penetrate. Aerate at least once per year.
Apply fertilizer
Boost growth with a balanced lawn fertilizer. Look for one with more nitrogen to encourage spread of grass plants. Organic options are also available.
Reseed bare patches
If existing grass is not filling in dead areas, overseed with a matching grass type. First rake the bare soil lightly. Then scatter seeds and tamp down gently. Keep newly seeded areas moist.
Adjust mowing height
Raise the cutting height of your mower. Taller grass encourages deeper roots and blade growth to fill patches. Cut no more than 1/3 of blade length.
Improve sunlight
For shady areas, prune back overhanging branches or nearby trees. Maximize sunlight to stimulate grass growth. Or consider shady, shade-tolerant grass mixes.
Top dress with compost
Spread 1/4 inch of compost over bare patches to enrich soil. Consider blending grass seeds into compost before top dressing.
Be patient
It can take weeks or months for dead grass to fully fill back in. Consistent lawn care and maintenance will promote spread into bare areas.
When to re-sod dead grass
If dead patches still remain after several months of care, re-sodding may be necessary. Here are some signs it’s time for new sod:
– Dead area is very large, over 4-5 feet across
– Damage extends several inches into soil
– Grass has failed to spread into bare patches
– Pet urine damage has left high salt content
– Shade issue cannot be resolved
– Weeds have invaded bare areas
To re-sod:
1. Remove dead grass and scrape area down to firm, moist soil.
2. Level area and fill any dips or holes. Compact the soil.
3. Lay sod strips, tamping edges together tightly.
4. Water sod daily for 2-3 weeks until established.
5. Consider mixing in soil amendment before laying sod.
Choose sod of a grass type suited to the lawn’s sun exposure and climate. Proper prep and care will help new sod patches knit into surrounding grass.
Preventing dead grass patches
Here are some tips for keeping lawn grass healthy and preventing dieback:
– Mow at proper height – not too short. Leave 3 inch blades.
– Water deeply and infrequently. 1-1.5 inches per week.
– Use a mix of grass types adapted for your climate.
– Aerate compacted areas in spring or fall.
– Apply fertilizer in growing season. Avoid excess nitrogen.
– Seed in fall for cooler weather growth.
– Treat thatch buildup that prevents air and water reaching roots.
– Check for chinch bugs and grubs. Use pesticides as needed.
– Prune trees and shrubs for optimal sunlight.
– Adjust sprinklers to avoid excessive overlap.
– Repair leaks and drainage issues promptly.
– Reseed high-traffic zones prone to dieback.
– Top dress with compost to improve soil.
– Limit pet access to areas until urine damage repairs.
– Remove leaf litter and debris promptly to prevent smothering.
– Consider screening excessive shade areas with shade-tolerant mixes.
With vigilant lawn care and prompt treatment of problem areas, you can maintain healthy grass and avoid extensive dieback and dead patches.
Conclusion
Dead patches of grass can be frustrating and unsightly. But in most cases, with proper care the lawn will recover and fill back in over time. Identify and address the underlying cause, then encourage regrowth by aerating, fertilizing, overseeding, and maintaining optimal mowing, watering, and drainage. For extensive dieback or recurring issues, re-sodding may be required. With persistence and care, your lawn can regain its healthy, lush appearance.
