organic_flutterby

I would think that using a good soil mix that drains well would help with that issue. It really depends on your conditions. I have mostly sandy soil and unless we have a rainy spell, the only thing I have seen out in my yard is some mushrooms. As soon as it dry back out, they are gone.

For what it's worth - I have constructed my raised beds out of AC2 treated wood (arsenic-free). I used 1" x 6" boards and they have now lasted for two seasons - going on the third season - so far.

Here is a link that might be useful: BsnTech Gardening Blog

I live in the Pacific Northwest and get rain a solid 9-10 months of the year. I have never had a problem with mold on the wood. My oldest bed is 12 years old and is now showing signs of minor wood rot where it touches the ground. It should last another 3 years at least.

I only use 2x12's (I like the depth) now since the 1 inch wood rots in about 5 years due to the amount of rain in the area. Also, I use cheap untreated pine for all the garden beds.

Your beds should last 5-15 years or so depending on the weather in your area and the thickness of your wood. Happy Gardening!