Is your school garden poisoning students?

Be Green Be Sustainable

With the push to be green and sustainable, many schools are turning to gardening to teach valuable skills to students.  Growing giant tomatoes means that you have to pull in some reinforcements.  Good sunlight, water, fertilizers and the dreaded pesticides. But something much more dangerous hides in the school garden soil.  Something that we though we rid schools of in garden lead

Lead in the School Garden Soil

Lead can be found in many things.  In the recent years, lead has been found in lunch boxes, toys, books, paint and many other common household products – think toothbrushes.  What you may not have expected is that lead could be found in soil.  Naturally occurring soil may contain lead, but typically these levels are below acceptable levels.  The problem usually arises when schools purchase top soil or new dirt to begin their gardening programs.  This purchased soil may come from areas were lead content was much higher.

80 mg/kg is the limit

The California EPA determined that 80 mg/kg of lead in soil may lead to increased of blood lead levels.   While this is a guideline, schools should really seek to have lead levels below this threshold to avoid adverse liability.  If you are going to start a gardening program at your school site, you should test your soil first.  If you are going to purchase top soil, you should buy OMRI certified products.  These can be found at

You can also look for tested and verified compost at

 What’s Next

School risk managers should consider publishing guidelines for their site’s PTA groups and staff to follow when setting up or maintaining a garden.  Consider setting up a list of approved soil products also.  In addition, schools may wish to test existing gardens to verify lead levels.

2 thoughts on “Is your school garden poisoning students?

  • It is very interesting to know that some of the plants are toxic themselve, such as Oleander, Yellow Oleander and Lantana. In my area it is very common to have them in the Public Parks, home gardens; though they are very toxic.

  • Thad Nosal • Good timing. EPA just released their new edition of “America’s Children and the Environment, 3rd edition” on Friday. The report shows trends for contaminants in air, water, food, and soil that may affect children; concentrations of contaminants in the bodies of children and women of child-bearing age; and childhood illnesses and health conditions. Reduction in reported blood lead levels is one of the better success stories in the report.

    EPA has been very active in school environmental health. Many of the resources they developed are available at, including model guidelines for helping states develop environmental health programs for schools.

    Do you know if you get LEED points or other credits for adopting gardening programs? I know the USGBC has a green schools initiative, including project management guides and methods for greening existing schools, but other than landscaping and IAQ, it didn’t look like they addressed curriculum/program aspects of a school day.

Leave a Reply

Your email address will not be published. Required fields are marked *