Think about your soil before planting your fruit tree…

Are you worried about planting fruit trees in your yard because you think the soil might be toxic? Well, you might not have to worry quite so much. The City of Toronto has put out a booklet called “From the Ground Up” which is a guide for soil testing in urban gardens. They developed the booklet based on literature review and consultations with experts. The full report is available at: toronto.ca/health/lead/soil_gardening.htm or you can click here to download your copy.

Essentially, this booklet will help you identify whether your site is high risk or low risk. Did you once have a gas station, a dry cleaner, a printing or auto-body shop on your proposed planting site? If you answer “yes” to any of these questions your site is considered high concern.

The booklet also defines areas of medium concern and believe it or not, former orchards are in this category because some orchards were (and still are) treated with toxic chemicals. Also of medium concern are infill areas, hydro corridors, and remediated industrial land.

Low concern areas include residential land, parkland, farmland and schools, though from our experience at Orchard People, some of the poorest quality planting soil is on school grounds and some residential areas as a result of poor building practices when contractors remove six to twelve inches of  healthy topsoil before constructing the new building and, after construction, replace it with just a few inches of poor quality soil covered with grass.

In a case like this, the soil on your site may of low concern, but instead it may be highly compacted and almost nutrient free. You can often tell just by digging a hole in your proposed planting area. Is the soil rock hard, gravelly and dry? Then it may be low-nutrient soil. Is the soil rich and dark and loaded with worms? Then you have good soil.

So here’s the good news. According to the conclusion of the City of Toronto  report, you can plant fruit trees in any of the three zones (yes, even the high concern zones) and you can safely harvest and eat the fruit while planting certain types of vegetables is not recommended.

As it turns out, fruit trees have their own system of cleaning the soil around them and ensuring the toxins aren’t drawn into the fruit. That is one of the things one of Ben Nobleman Park’s first volunteers, Jessica Langer Ph.D, discovered when she researched and wrote an academic study to discover if urban fruit is safe to eat. You can read her report here to see what she discovered.

If you are thinking of planting on a high or medium concern site, there is something you may want to consider. Theoretically a fruit tree planted on this site should produce fruit that’s safe to eat. But will the young tree survive in such poor conditions? Fruit trees draw their nutrients from the soil and poor and toxic soil may not provide sufficient nutrients to sustain a vulnerable young fruit tree. Young fruit trees are delicate. If they do not get the nutrients they need when they are very young, it can affect their future health and development.

So, the moral of the story is that where ever you plant your fruit tree, you need to constantly working to improve the soil. One of the simplest way to do this is to add compost or well rotted manure around the roots of your tree each spring.

Susan Poizner is the Coordinator of Ben Nobleman Park Community Orchard and the Director of Orchard People and the author of “Growing Urban Orchards: The Ups, Downs and How-Tos of Fruit Tree Care in the City”. For more information visit www.orchardpeople.com.