There are a dozen variables I can think of right off the bat that would affect the longevity or serviceability of wooden barrels. Most should last 3 years +.

Please, allow me to discourage you from trying the drainage arrangement you suggest. If you set your container up the way you noted, the bottom of the container will quickly turn into an anaerobic bacterial nightmare. Forget the drainage layer - they are ineffective at anything but reducing the amount of soil required to fill the container or for adding/eliminating weight (depending on what you use). Your plants will do best if you use a soil that drains well and fill the container to the desired level with soil only. Drain holes should be at the bottom or where bottom meets sides.

To learn more about how water behaves in container soils, read the thread at the link provided.

Here is a link that might be useful: About Water in Containers

You can make it last longer by coating the inside with spray-on automotive undercoating. Treat the outide with a good penetrating oil finish.

I second holes drilled in the bottom --- residual water will rot the wood too quickly.

I found I needed to put in small nails under the top hoop to keep it in place as the wood gradually dried. Would have been easier to do on a new barrel half. The automotive undercoating spray may alleviate that situation.

My concern wasn't for the container, it was for whatever plant material might be planted in it. ;o)

Al

Whiskey or wine barrels are *designed* to hold liquids. They last many years, outdoors, as long as they have soil in them to keep some moisture on the wood.

Used with a liner (a small pond), so the sides/bottom are dry, they decay rapidly.

I use lots of whiskey barrels for my fruit trees. My husband drills large holes in the bottoms with a doorknob bit. Smaller holes tend to close up as the wood swells from moisture.

I have barrels that are over 5-6 years old that are in great shape. I've yet to have one fall apart. They do get termites on the bottoms, if set directly on the lawn.

They are fairly inexpensive, look neat, you can weedwack around them easily. They help me use lower areas of the property for growing, since I can plant a fruit tree in them, knock out the bottom, and the main rootball is well above the temporary flood zone that would kill trees planted at ground level..

Lisa

I have a couple that were here when I bought my house, 20 years ago. They are getting a bit decrepit - this will be their last season :-)