Are cement drain tiles safe to use in the garden?

Hi,

Does anyone use old (decades old) cement drain tiles in their gardens?

I have heard that drain tiles can be used for planting strawberry plants inside them and then the strawberries would hang over the sides. Drain tiles can also be used to support a trellis in the garden. I have used them for this in the past.

But now I am wondering: Are they safe to use or is there something in the materials used to construct the drain tiles that would make them unsafe for being used in the garden? I have done an internet search but have yet to find an answer.

If they are safe, I have several that I can use. They look similar to the ones in the picture (the picture is from http://appledrains.com/drains/wp-content/uploads/2012/07/20120629_091011.jpg). They look like the cylindrical ones in colour and the octagonal one (in the middle) in shape.

Edit: When I say they look similar to the cylindrical ones in colour I mean that they look grey. The ones I can use look a lot cleaner and some have already been sprayed with a hose.

Thank you.

 

The clay drain tiles should be good for anything that doesn't mind confined roots. The grey ones are made of concrete and may not be suitable for plants that like acid soil, since they will leach calcium carbonate into the soil.

 

I've used old drain tiles in the past without issue - I used them to create a border along a path and planted them with annuals such as petunias and fuchsias.
Obviously you would have to plant something that will remain small but if you place them in a flower bed, or sunk into the ground, the roots will have a chance to reach down and spread out.

 

Thank you both for your replies.

Hi vitog, I am going to be using some drain tiles this year as support for a pea and bean trellis. The drain tiles will be in the ground. Some seeds will be planted very close to the tiles but peas and beans don't require acidic soil as far as I know. I might try some smaller plants inside some of the remaining drain tiles. Thank you for telling me about the calcium carbonate in cement tiles. I wasn't aware of that.


Hi pmurphy, I won't be putting any large plants in the tiles. With some of the ones I have left over after making the trellis supports I might try some smaller plants. I like your border idea. The tiles were used as a small border before but they were on their sides end to end - so a grey border without any colourful plants.

 

If you are worried about alkalinity of the concrete, just put them in a wheelbarrow, get a gallon of vinegar and slosh it over them to neutralize them. Give them a rinse after an hour. Done.

In my experience, moss and acid lovers will start to grow on & around concrete after it is a few years old, when the pH of the concrete rises, particularly in our rainy coastal climate. Are there any mosses or algae growing on these drain tiles?

 

Thank you for the advice. I knew vinegar can be used on weeds but I didn't think to use it on the drain tiles.

There is some moss on some of the drain tiles (they aren't covered in moss). Some of the moss appears to be partly red in colour. The tiles that I am using for the trellis supports don't seem to have any moss on them (at least I didn't notice any when I thoroughly sprayed those tiles with a hose to try and clean them).