If you've ever stumbled upon a lawn that's been recently aerated, you might have wondered what all those weird plugs of uprooted earth are for. It may look funny, but as any proud lawn owner will tell you, those weird plugs may be the key to keeping your yard looking lush, green, and healthy.

But just what is lawn aeration and why is it so necessary? Check out our lawn-aeration FAQ to determine if your lawn can benefit.

What is lawn aeration?

For a lawn to grow healthy, it needs three basic things: air, water, and nutrients. But often, problems such as compacted soil or excess thatch (organic debris that builds up on top of the lawn) can prevent the grass roots from getting the water, nutrients, or oxygen that they need.

When you aerate your lawn, you're literally poking air holes in it, making it easier for the grass roots to breathe. But you're also providing a path for water and nutrients to get past the layers of thatch and soil to nourish those roots.

How can I tell if my lawn needs aerating?

Aeration is good for just about any lawn, but there are some lawns that may need it more than others. If your lawn gets heavy use and lots of foot traffic, the soil is likely to be fairly compacted and may benefit from aeration. Furthermore, lawns that were put down during construction of a new home or lawns that were established with sod may have problems with root development, so lawn aeration can benefit yards in both of those scenarios.

But even if your lawn doesn't fall into one of these categories, it may still require aeration to stay healthy. Here are a few telltale signs to look for:

• Lawns that have standing water puddles not caused by heavy rain
• Patches of grass that won't stay moist, even with excessive watering
• Lawns with excessive water runoff
• Lawns with lots of thin, patchy areas
• A layer of thatch that's thicker than a half inch
• Lawns with heavy, clay soil
• Lawns with large patches of clover
• A lawn that feels spongy or springy when walked upon (which can indicate a thatch problem)

If you still have any doubt, there's a simple test you can perform to check if your lawn is too compacted. Using a screwdriver, pencil, or small shovel, try to push a hole into the lawn. The tool should slide in easily; if it doesn't, you likely have a soil-compaction problem.

You can also dig up a piece of the lawn and examine the grass's roots. The roots should reach about 4 to 6 inches into the soil. If the roots are significantly shorter, it's time to aerate.

When should I aerate my lawn?

For the best results, experts recommend aerating your lawn during the growing season, since it gives the grass time to correct and grow in healthier and thicker. If you have warm-season grass (common in hotter, Southern climates), the best time to aerate is in the spring. If you have cool-season grass (common in cooler, Northern climates), it's best to aerate in the spring or fall.

How often should I aerate my lawn?

As a general rule of thumb, aerating once a year is a good idea. If you have sandy soil, however, you may be able to get away with aerating every other year, while lawns in very dry climates could benefit from twice-yearly aeration.

If you've just installed sod, it's best to wait at least one year before aerating in order to give the roots time to take hold.

Can I aerate my lawn myself?

The short answer: yes, you can. But only if you don't mind a lot of hard work.

To aerate your lawn yourself, you'd need to use a heavy pitchfork or hollow tiner (similar to a pitchfork, except the tines are hollow and remove soil), and pierce the entire lawn, making holes that are 2 to 3 inches deep and around 3 to 4 inches apart.

There are also special lawn-aerating tools that use spikes to punch holes in the grass (They even make spiked shoes for this purpose!), however, spikes are not as effective as true core aeration since they don't remove any compacted dirt. In fact, there's the possibility that this type of lawn aerator can actually make soil compaction worse.

Why should I hire someone to do it for me?

The answer might seem obvious, but it's important: it's because (1) you won't have to do anything and (2) they'll do the job right. Lawn aeration services use a gas-powered machine to tackle an entire lawn quickly and evenly. It isn't free, but it saves you a lot of time and sweat, and almost always produces better results than a DIY job.

How much does lawn aeration cost?

That largely depends on the size of your lawn, but, roughly speaking, you can expect to say anywhere from $75 to $125 for a professional job. By comparison, renting a lawn aerator to do the job yourself will cost you between $40 and $80 for the day, meaning the DIY approach doesn't really save you that much dough. And, of course, you can always check Groupon for deals on professional lawn aeration—a win-win since it saves you a lot of money AND a lot of hard work.