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Tuesday - February 24, 2015

From: Newtown Square, PA
Region: Mid-Atlantic
Topic: Diseases and Disorders
Title: Safe Concrete Planters For Plants?
Answered by: Anne Van Nest

QUESTION:

We are building low concrete walls around a patio (in Washington, DC). Can we create the walls to act as planters or will the lime leaching make the soil too inhospitable for most plants?

ANSWER:

Beck Cowles has written a good article about building raised beds for plants and includes the pros and cons of the different materials available. It is on the Ecology Center website. This is a non-profit group in Berkley that has been focusing on the environmental impacts of urban living for over 40 years. Beck says that concrete less than one year old can leach lime, affecting soil pH and suggests that lining the planter can prevent the lime from entering the soil.

As an alternative to this, Claudia Brownlee on her website, Artistic Garden talks about making hypertufa containers out of cement and soaking the containers for at least 3 days to leach the excess lime out so the planter won't be toxic to plants. She also suggest if containers are too big for soaking that hosing them down 2-3 times a day for 3-5 days will also work. Other suggestions include leaving the container outside for 1-2 months so the rain leaches out the lime. Good luck with your planter.

 

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