Lawn aeration is the process of removing small plugs of soil from your lawn to allow air, water and nutrients to better reach the grass roots. This helps reduce soil compaction and thatch buildup for a healthier, greener lawn.
A core aeration, where plugs of soil are removed, is the most effective type of aeration but also the most labor intensive. You can rent an aerator or have a lawn service perform the task. Aeration is typically recommended once per year, in early spring or fall when grass is actively growing. But is aerating your lawn twice a year beneficial or just extra work? Here’s what you need to know about double aerating your lawn.
What are the potential benefits of double aerating?
Double aerating your lawn, or aerating twice per year instead of just once, can provide the following potential benefits:
– Further reduces soil compaction for improved air and water movement. Heavy traffic from kids or pets can quickly re-compact the soil after a single aeration.
– Provides extra relief from thatch buildup. Thatch is a thick layer of dead grass stems and roots that accumulates over time. It prevents water, air and nutrients from properly filtering down to the soil and grass roots.
– Allows more opportunity to apply additional amendments. When you aerate, it’s a good time to apply compost, fertilizer, overseeding and other amendments down into the holes. Doing this twice per year provides more chances to fortify your lawn.
– Improves root development. The extra aeration helps the grass plants develop deeper, more extensive root systems because they have more room to spread out. Stronger roots improve the overall health of the turf.
– Can reduce weed pressure. Lawns with less compaction and thatch tend to get fewer weed invasions because the grass is thick and healthy enough to choke out weed seeds. The improved growing conditions favor the desirable grass.
– Keeps the lawn greener in hot weather. Better moisture retention and reduced stress on the grass plants from soil compaction means the lawn stays lush and recovers faster, even during the dog days of summer.
So in many cases, double aerating can take an already healthy lawn to the next level, or help turn problem areas of compacted, thatchy turf into thicker, more vigorous grass.
What are the potential downsides of double aerating?
While the benefits are significant, there are also some potential downsides to keep in mind with double aerating:
– It’s a lot more work. Aerating is labor intensive, so doubling the frequency means double the effort. Hiring a service is costly, renting an aerator can be inconvenient, and doing it yourself is exhausting.
– Possible lawn damage if done wrong. Using an aerator takes some practice—going over the same spots repeatedly can tear up the turf and leave bare patches if you’re not careful. There’s more opportunity for aeration mistakes when you double up.
– May be overkill for many lawns. Most typical home lawns with average use probably only need a single yearly core aeration. Soggy, compacted soil or very high traffic may warrant double aeration. Otherwise it may provide only marginal additional benefits compared to a single annual treatment.
– Not advisable during grass establishment. You should wait until new grass seedlings are mature before aerating, so double aerating isn’t recommended if you’re also overseeding or laying new sod that season.
– Requires more watering. Aerating opens up the soil and removes some grass shoots, so the lawn needs more frequent irrigation to recover and fill back in. Doubling the aerations means double the water demands.
– Can increase weed invasion risk. Those open holes left behind are opportunities for crabgrass, dandelions and other weeds to sneak in and get established. Good follow-up weed control is essential.
So weigh the pros and cons carefully before deciding if your particular lawn would benefit from double aerating instead of the standard once per year.
When is the best time to double aerate?
Ideally, you should aerate cool season grasses like fescue and bluegrass in early fall and again in early spring. Wait 4-6 weeks between aerations.
For warm season grasses like bermuda, zoysia and buffalograss, the best timing is early to mid spring and again in mid to late summer. Also wait 1-2 months between sessions.
The exact dates will vary based on your climate and the 10-day weather forecast—look for mild temperatures around 70 F, good soil moisture, and an extended period of dry weather in the outlook.
Avoid aerating during hot, dry summer months or when the lawn is overly wet and muddy. Also steer clear of peak growth seasons when the grass is least tolerant of disruption.
How to get the most out of double aerating
Here are some tips to maximize the benefits from double aerating your lawn:
– Use a core aerator, not a spike aerator. The spike types just poke holes in the ground but don’t remove plugs. Only core aerators provide real compaction relief.
– Adjust the tines to remove cores 2-3 inches deep. Shallow aerating in top layers won’t be as effective at impacting compaction. Go deep enough to reach compacted subsoil layers.
– Leave cores that break up on the surface to decompose and add organic matter back into the lawn. Or rake and bag them to remove excess thatch accumulation.
– Water thoroughly after each session—the soil and roots will be stressed and need moisture to recover. But don’t aerate soggy ground.
– Follow up each pass with fertilizer, compost and overseeding for enhanced recovery. Time it right before a period of healthy grass growth.
– Let the grass re-establish before heavy use. Avoid sports, foot traffic and mowing for about 2 weeks after aerating.
– Adjust your mowing height up about 1/2 inch after aerating. This reduces lawn stress and allows the leaves more energy reserves.
– Control weeds proactively. Apply preemergent in spring and weedkiller soon after disruptions to avoid weed invasions in the disturbed turf.
– Consider adding amended top dressing like compost. This fills the holes and further improves soil structure in aerated lawns.
Double aerating does take more effort and care to get right. But for lawns with serious compaction issues struggling to absorb air and water, the benefits of extra aeration can certainly justify the work involved.
Should I aerate before or after overseeding?
Aeration and overseeding are two common lawn care practices that help improve the density, thickness and health of turfgrass. But what order should you do them in—aerate first and then seed, or vice versa?
Reasons to aerate before overseeding
– Aeration reduces soil compaction and helps loosen the ground, allowing new grass seeds better contact with soil to aid germination.
– The holes left behind by core aeration provide perfect seedbeds full of loose, fertile soil for overseeding.
– Removing plugs helps reduce excessive thatch buildup before seeding, again improving seed-to-soil contact.
– Any fertilizers or amendments you apply will more effectively move down into the turf following aeration.
– Seeds fall into the aeration holes protecting them from birds, wind and rain washout.
Reasons to overseed before aerating
– Seeds dispersed before aerating will settle into the lawn canopy, reducing exposure after the turf is disrupted.
– Germination may be slightly faster before aeration, so you capitalize on early fall growing conditions.
– Established seedlings are less vulnerable to damage and desiccation when the aeration cores are extracted.
– There’s less risk of weed seed germination in the open cores if grass seed has a head start before aerating.
So in summary, aerating first provides the best seedbed and helps the new grass take root. But seeding first lets it establish briefly before disruption.
Conclusion
Most experts recommend core aerating just before overseeding a lawn. Aerating 1-3 days prior gives grass seeds the advantage of ideal germination sites. Just be sure to water immediately afterward and walk the area to work seed into the holes. However, you can achieve success aerating a few weeks after overseeding when the young grass has anchored down.
When to aerate lawn in winter, spring, summer, fall?
| Season | Best Time to Aerate |
| Winter | Not recommended – turf is dormant and ground is frozen |
| Spring | Early to mid spring when soil reaches 50-60 F |
| Summer | Optional light aeration for warm season grass |
| Fall | Early fall for cool season grass |
The ideal time to aerate depends on the type of grass and seasonal conditions:
– Cool season grasses like fescue, rye and bluegrass should be aerated in early fall when temperatures cool and the turf resumes growth after summer dormancy. Early spring is another option.
– Warm season grasses like bermuda, zoysia and buffalo tolerate summer aeration if needed, but are best aerated in early to mid spring as they green up.
– Winter aeration is not recommended due to frozen, muddy ground and dormant turfgrass.
– Look for 50-68 degree soil temperatures for active grass growth without excessive heat stress.
– Avoid periods of peak summer heat, cold winters, or before extreme weather shifts like monsoons.
– Allow 4-6 weeks between aeration sessions for the grass to recover before disrupting again.
Proper timing maximizes the benefits while minimizing stress to the turf. Aerate when the soil is moist but firm and the forecast is favorable.
How often should you aerate your lawn?
Here are general recommendations on aerating frequency:
– Low traffic lawns with sandy soil: Every 2-3 years
– Clay soils or moderate foot traffic: Annually
– High traffic areas, sports fields: Twice per year
– Very compacted soil, persistent thatch: Up to 3 times per year
– New lawns: Wait one year after establishment before first aeration
– After overseeding or sod: Wait 4-8 weeks for new grass to anchor before aerating
– During drought: Postpone until some rainfall provides moisture
Increase frequency for high clay content, excessive thatch, heavy use, or large pets. Sandy, loamy soils that absorb water well need less frequent aeration. Gauge by overall lawn health and recovery after aerating.
Do I need to aerate my lawn?
Consider aerating your lawn if:
– Puddles form or water runs off instead of soaking in, indicating soil compaction
– Footprints remain visible after walking across the grass
– Lush growth in spring is followed by summer die-off
– Grass roots are shallow and easily pulled up
– The lawn feels spongy from excessive thatch
– It’s been 2+ years since the last aeration
– Weed invasions, moss and mushrooms are increasing
– Grass recovers slowly from drought stress
– Seed germination is spotty after overseeding
– Soil test shows adequate nutrients but turf is thin and patchy
These signs indicate potential compaction, thatch issues, poor drainage or limited root development that aerating can improve. But lawns growing vigorously with deep roots and minimal runoff generally don’t need aeration.
Should I aerate before or after mowing?
It’s best to mow the lawn about 2-3 days before aerating. This allows grass blades time to grow back slightly before being removed by the coring aerator. Mowing right before aeration can scalp the lawn, leaving bare spots.
Mowing a few days prior also ensures debris like leaves are cleared away before holes are punched. Long clippings can catch in the aerator tines and leave messy clumps. Having a freshly cut lawn also makes it easier to maneuver the aeration machine evenly across the turf.
After aerating, hold off mowing again for about a week. This gives the turf time to start knitting back together before being cut. In general, allow 2 weeks rest from all foot traffic, mowing and equipment use for the lawn to recover after aeration.
So in summary:
– Mow 2-3 days before aerating to clear debris and allow some re-growth.
– Do not mow directly before aerating to avoid scalping.
– Wait 5-7 days after aerating before mowing again.
Proper mowing before and after helps minimize lawn damage from the aeration process.
How long does lawn aeration take?
The time required to aerate your lawn depends on several factors:
– Size of the lawn – larger lawns take more time
– Scope of aeration – whole lawn vs problem areas
– Type of aerator – walk-behind and tractor mounts are slower than tow-behinds
– Number of passes – More passes provide better coverage but extend time
– Soil conditions – Hard, compacted soil is slower going
As a general guideline for an average 5,000-8,000 sq ft suburban lawn:
– Manual spike aerator: 1 hour
– Walk-behind core aerator: 2-3 hours
– Tow-behind core aerator: 1-2 hours
– Tractor mounted aerator: 2-3 hours
– Additional passes: Add 30-60 minutes each
Work in smaller sections and make multiple passes for complete coverage. Let the aerator pull you at natural walking speed for best results. Aerating takes some time but leads to a healthier lawn.
Conclusion
Double aerating your lawn each year provides extra help relieving soil compaction, reducing thatch, increasing drainage, encouraging root growth and thickening turf density. The key question is whether the doubling benefits outweigh the added effort and risks for your particular grass and conditions. Careful timing and preparation can maximize the advantages while minimizing negatives. Evaluate your lawn’s specific needs and make use of available resources like soil tests to determine if extra aeration could be helpful. But in most average home lawns, following the standard yearly schedule is sufficient to keep the grass healthy with minimal work involved.
