Question of the Day should I power Rake my lawn?

I get asked all the time should I Power Rake my lawn?

I only recommend dethatching or power raking lawns that suffer from an extremely thick thatch layer that is between 1.5-3 inches thick. The reason is because dethatching causes extensive damage to a lawn and is extremely labor intensive. If your thatch layer is less than an inch and a half, then I recommend aeration in the spring and fall as the best method to reduce your thatch. Core aeration pulls plugs of soil and thatch out of the lawn and the cores of soil breakdown and populates the thatch with millions of soil microbes that help biodegrade the thatch naturally.
So why does my landscaper do it.



I had a conversation with a landscaper about this.
Me: Why do you power rake these lawns? You know it harms the grass and the roots and stresses the lawn?
Landscaper: It makes the lawn look clean which the customers like and then we get to seed and put top soil or peat moss on the lawn so we can charge them more for the spring cleanup.
Me: Why don't you just core aerate?
Landscaper: This way we can charge to aerate or the can substitute it for power raking.
Power Raking
Power Raking generally involves using fixed knife type blades that slice the thatch and then rips it out. The dethatching machine is set high so that the blades just skim the surface. Power raking does cause extensive damage to the live grass and the grass' root structure.
If you insist on Power Raking it can be done in the spring If you are power raking to remove winter debris I recommended to do it before the lawn starts growing to avoid setting the lawn back during the critical spring time growth. Power raking should only be done when combined with overseeding I recommend doing it in early spring to allow the new seedlings plenty of time to get established before the summer drought and heat. Early fall remains the optimum time for any overseeding and should be done with a core aeration, because you avoid the summer heat and drought and the new seedlings do not have to compete with the spring germination of weeds.

Lawn aeration involves the removal of small soil plugs or cores out of the lawn. Although hand aerators are available, most aeration is done mechanically with a machine having hollow tines or spoons mounted on a disk or drum. Known as a core aerator, it extracts 1/2 to 3/4 inch diameter cores of soil and deposits them on your lawn. Aeration holes are typically 1-6 inches deep and 2-6 inches apart. Other types of aerators push solid spikes or tines into the soil without removing a plug (spiking). These are not as effective because they can contribute to compaction. Core aeration is a recommended lawn care practice on compacted, heavily used turf and to control thatch buildup.

What will aeration do for my lawn?

As lawns age or sustain heavy use from play, sports activities, pets, vehicle traffic and parking, soil compaction can result. Soil compacting forces are most severe in poorly drained or wet sites. Compaction greatly reduces the pore space within the soil that would normally hold air. Roots require oxygen to grow and absorb nutrients and water. Compaction reduces total pore space and the amount of air within the soil. It has a negative impact on nutrient uptake and water infiltration, in addition to being a physical barrier to root growth. This results in poor top growth and lawn deterioration. Core aeration can benefit your lawn by:

	Increasing the activity of soil microorganisms that decompose thatch.
	Increasing water, nutrient and oxygen movement into the soil.
	Improving rooting.
	Enhancing infiltration of rainfall or irrigation.
	Helping prevent fertilizer and pesticide run-off from overly compacted areas.

How do I know if I need to aerate?

If in doubt about aeration, remove a square foot section of lawn at least 6 inches deep. If grass roots extend only into the first 1-2 inches, your soil may be compacted and could benefit from core aeration. Expect a seasonal effect with cool-season grass roots being shortest in late summer and at their greatest depth in late spring.

Other reasons to aerate include:

	Your lawn is heavily used or driven upon on a regular basis, causing the turf to thin or look unthrifty.
	The thatch layer is in excess of 1/2 inch.
	You have a heavy clay soil.