How do you keep wooden tubs and window boxes from rotting out?
Use wooden containers made of redwood or cypress, both very resistant to decay. Other woods must be thoroughly treated with zinc or copper naphthenate (this one leaves a green stain). Do not use creosote or pentachlorophenol as a preservative, both harm plants. Liners of copper, heavy polyethylene film, or several layers of building paper also help prevent decay.
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