Garden wall cleaner & effect on soil...

[andrewmoquin]

This is a border-line garden query, it's got a home DIY twist to it but it still relates to my garden plans so here goes....

I'm almost done with the installation of a retaining wall out the front of the house, it's looking great and I've got the garden all planned out and ready to be planted in spring - however I have noticed that some of the retaining wall capping has some sort of motor oil or grease stains on it from the walls previous owner (we purchased used blocks and capping). I've tried to get this off with a concrete and paver cleaner and some elbow grease with a scrubbing brush however it's only moved it a bit.

My question is, do any of you know of a good product that will remove these stains? Also, with the run off into the garden, will this remain in the soil and kill off any plants or should it have disappeared within a few months (there are none planted at the moment, will do that in September). Last thing I want to do is have a great looking wall and dead plants.

[marmite]

Have you tryed using an engine cleaner, this side of the pond its called swarfeega. As for the being green it has not affected my ground but I only grow flowers in that bit. Could the stains be painted over, it would mean doing the whole wall. A job for the wife while you have a beer and watch it dry. Regards from Marmite. Off for some fresh medication.

[2dogs]

hi andrew
i dont think anything will remove motor oil once it has been absorbed by the concrete! the brick acid ( concrete cleaner) will only remove it so far..
however, if its only on the cappings, i cant see it affecting your plants,because rain water insnt going to shift it either!!
or
you could just replace the stained cappings with new ones.