is it safe to combine asphalt and top soil in raised gardens?

Question

i built two raised gardens that are three feet high. i lined the first foot with asphalt from my driveway to serve as irragation and am planning on adding the other two feet with top soil and peat moss. is this safe?

Answer 1

My first thought was "This was a really bad idea".

I assume you are growing food product. The two feet of soil between the plants and the asphalt is a good idea.

We all know things grow through asphalt. I just do not know if it puts off any chemicals that would end up in your vegetables.

Answer 2

Asphalt at the bottom will not irrigate. It may prevent drainage resulting in a boggy wet growing habitat. Some plants love wet feet (cyperus, sedge, sweet grass, reeds) I wouldn't recommend adding more asphalt to the beds, potting soil and peat moss, dead decaying leaves, straw, manure or other organic material is preferable.

Answer 3

I answered this question before but you explained it better this time. I think it would be perfectly safe as you described it. Good idea to think about the irrigation.