[pepsi100]

I have railway sleepers in my garden, sort of a wall holding my raised garden

They are full of pitch and tar (to save them rotting) they are several years old

There are gaps in them, I am wondering if I can put plants in the gaps and would they grow ?

If so, what kind of plants

I was also thinking of drilling holes to make a kind of bug hotel

Any ideas or recommendations really appreciated

[New shoot]

I think the pitch and tar will probably kill any plants you put in there and bugs won’t like it either.

If you want to try with the plants, it would be ones like creeping Sedums sold as alpines, but I would try a couple first to see what happens.  They may just curl up and die.