Treated lumber many new gardeners and even experienced ones turn to treated lumber when sourcing materials for raised beds due to its added protection against moisture and the associated rot and bug damage.
Pressure treated wood for raised beds safe.
The safety of pressure treated wood for garden beds depends on what preservative was used to treat the wood.
Lamiot wikimedia commons pressured treated.
Up until 2003 the most common preservative used for pressure treated wood was chromated copper arsenate cca a compound using arsenic.
Joe mabel wikimedia commons there is a long standing controversy in the field of organic gardening.
With a few precautions.
A barrier would not only prevent the dirt from making contact with the lumber but also help extend the life of the lumber by reducing the water exposure.
If you do use any pressure treated lumber you would want to use thick plastic or some other barrier between the soil and the wood to be on the safe side.
Wood treated with chromated copper arsenate or cca can leach toxic arsenic into soil.
From what i ve seen the consensus is that the chemicals do leach out of the wood into the soil and are uptaken by the plants in very small amounts.
Is it safe.
Here s what i know.
Can pressure treated wood be used as part of an organic vegetable garden.
Yes the new pressure treated wood is safe for use for raised garden frames.
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.
He stated in a bulletin titled treated wood in raised bed gardening scientific evidence and data have shown that using pressure treated wood for raised bed or box gardening is safe to adults and children in terms of the plants grown and used in these containers he further explains all chemicals in consumer products have a toxicity and most are very low so they are not a problem especially those regulated by the federal government.
Concerns have focused on the leaching of arsenic from pressure treated wood into the soil contaminating plants and people.
However while treated lumber will hold up better over time it can also leach harmful chemicals into your soil.
The safety of pressure treated lumber for raised bed gardens has been examined by several researchers.
See additional resources below.
Wood that isn t pressure treated tends to rot fairly quickly in contact with the soil.
He stated in a bulletin titled treated wood in raised bed gardening scientific evidence and data have shown that using pressure treated wood for raised bed or box gardening is safe to adults and children in terms of the plants grown and used in these containers.