I have both. One advantage is that the soil gets warmer more quickly in my raised beds (pretty important here, as we are slow to get ground temps warm enough). Second, they drain better (also important because of the massive amounts of rain we can get here usually until 7/4). Third, I don't walk on my raised beds so they stay nice & fluffly. Fourth, they just look pretty.

But, like I said, I do both. But for some of my veggies the raised beds work great, and others the ground is just fine.

Better soil, better drainage. I tried growing onions and garlic last year and nothing could bulb up in that compacted clay soil. Carrots also did poorly. The drainage problems were also an ordeal.

I have to say, I see vast improvements in the quality of my plants compared to each. Utilizing beds also let me make a lot more efficient use of a small space. We've seen stupid crazy amounts of rain, but the drainage for all the bes has been excellent. Building them was a long, on going process this year, but the end result is going to be many years with better gardening.

I have a raised bed. It made the most sense to me - my yard is only .58 acres with not a lot of room in full sun so I had to locate my garden in the middle of a beautiful patch of grass. I didn't want to constantly have to dig grass out of the garden! I also had very sandy soil with very little organic matter. I did an enormous amount of soil prep work double digging down 2 feet and building the soil up 12 inches & enclosing -- however it was a one time deal! All I do now is add compost and organic fertilizer and rake it in. There is absolutely no tilling, little to no weeding, the soil stays friable, and I can grow beautiful root crops. As a "woman of a certain age" who does all gardening herself with no power tools - the ease of putting in new crops was the biggest selling point to me.

Also if they are high beds the bunnies dont bother them. (at least the ones on my yard)

Where I live, it's all rock, so we have no choice. When I moved here, I found out that a pick ax is the garden tool needed, so I trucked in soil and put a fence around it. Now my soil is lovely.

As I age, I see that the higher the plants are, the easier it is to garden. Right now I could gofor 4 foot high raised beds! lol

Better drainage, deeper soil (for most gardens), less bending. But, there are two disadvantages. They are expensive (materials AND labor) to build and maintain, and raised soil dries out faster. For small scale, labor-of-love intensive gardening, they make a lot of sense.

Raised beds make a lot of sense in a lot of situations as mentioned already. But let me give another perspective from the dry west. Out here on rapidly draining clay loam soil the only way to garden is in furrows. Any kind of raised bed dries so fast it is difficult to even get emergence. Planting in a furrow or basin is easier to water and keep moist.

Advantages (for me):
-The mix is easier to work with than earth soil.
-I can confined space makes me grow more intensively
-root crops grown nicely
-I can use PVC hoops for: protect from frost/freeze and to support deer block or cloches.
- Looks pretty.

This is not to say that the above items can not be done with an in-ground garden.

Disadvantages:
- probably limits how much I can grow (despite intensive gardening)
-initial cost/work

For me it is horribly dense clay soil that has a 2 week time in the spring and a 2 week time when it starts raining in the fall for digging, and GOPHERS!!!!! They will eat anything that comes up in the ground within a couple of days!
They also keep things neat, the soil stays diggable, just add compost and dig in each year, less weeding.
Nancy

I'm really glad you asked this question, and I've appreciated all the answers -- I too was wondering how come so many raised beds! Now I understand.

Thank you for all the interesting replies! How high do you usually make a raised bed? Can it be 4 inches, or 40 inches?

Coincidentally I've had well-drained, sandy or gravelly loam in the gardens at both my houses. Raised beds don't make any sense in an upland position with sandy or gravelly subsoil, because it already drains quickly. Add a lot of compost and organic matter, or do some lasagne or sheet composting, and sandy loam makes awesome soil. After a couple years the soil becomes rich and friable.

Have to work around the tree roots from the large canopy trees sometimes though!

A lot of the reasons for raised beds never made sense to me where I garden.
Bad soil can generally be improved as easily as replaced. But then I don't live on bedrock either, so I can see that.
Warms up more in the day? If so, it cools down more at night. In point of fact, neither is true. At least in my situation where I made a point of putting this to the test. IMO, it's an urban gardening myth. My own data bears this out. Your mileage may vary.
Weeds? Not a big deal for me. I work the top inches of soil every year and I know how to use a hoe properly.
Better drainage? A disadvantage in my sandy loam. You have to consider your own situation.
Don't have to bend over so far? Very true, but not an issue for me... yet.
Yet after all of my disinterest in raised beds, I did, however, break down and build a 12" raised bed for one reason. Carrots. What a difference. But they require water each and every day, or splitting is still a problem.

lots of reasons why raised beds?

saves doing any tilling or digging so saves teh back, alos depending on height saves bending our latest beds make gardening so much easier.

good for moisture control, no weeds, and these new ones up out of teh reach of any creature that digs,

len

Here is a link that might be useful: lens bale garden

I have a tiny yard of gravel over sand. Love my raised beds.