Untreated Lumber For Raised Beds
My current raised beds are made from 1 untreated pine and last approximately 10 years.
Untreated lumber for raised beds. This publication from pennsylvania state university does a good job describing the risks of using both cca treated wood as well as acq treated wood. Garden use of treated lumber. Yes untreated wood will decompose over time but because it is untreated you reduce the risk of potential toxins moving from your wooden beds into that organic veggie garden you re starting to keep your family fed well. Of course the primary concern with using pressure treated wood in raised bed gardens has been with the arsenic in cca chromated copper arsenate treated wood.
A redwood raised garden bed however can last up to 20 years. If your raised beds will be exposed to a lot of moisture wood like pine may only last a few years. How long will untreated wood last in raised beds. Untreated soft wood like pine planks or heat treated pallet wood only lasts 3 5 years outdoors using pallets for raised garden beds i built my very first raised garden beds using wood reclaimed from pallets.
It was a nightmare getting the planks off undamaged but we got there eventually. As such it s natural to be concerned that an untreated pine raised garden bed will deteriorate. It rotted off at ground level in less than a year. Most people gravitate towards treated pine lumber for its ability to stave off decomposition.
Current treatments such as alkaline copper quaternary acq are deemed low risk by the epa and designated safe for use around humans pets plants and vegetables. But i also live somewhere where the rain is moderate and the drainage is very good. Compared to untreated wood pressure treated lumber lasts longer and is available at a comparable cost. As we are learning with composting decomposition is a natural part of any earth derived material.
Untreated softwood will last you 2 years tops before there is fairly significant rot i used an untreated length of wood as a tree stake once because it was all i had and i didn t want to buy another one. A cedar frame can last up to 10 years but one made of douglas fir may last only 5 to 7 years. Untreated wood untreated wood in general can make beautiful rustic looking raised beds. The only thing to keep in mind with using these products is that they will break down much faster than other options.
Wooden planters built out of untreated wood will probably last much longer than you think. Gardeners have used pressure treated wood for decades in raised beds and as posts but on december 31 2003 the environmental protection agency epa banned the sale of lumber treated with chromated copper arsenate cca for residential use.