Planting things through plastic used to make me think of the Hmong strawberry growers, who use that method extensively. For some reason, it didn't sit well with me. Then I realized that it was what they did before putting it down that bothered me: Fumigate with pesticides and herbicides so powerful they have to put skull-and-crossbones tape all around the field. This is because they plant the same thing over and over and over, so nasty plant-specific pathogens build up. But come to find out, there are other good reasons to use plastic. For instance, see that little garlic sprout coming through the plastic at lower left? That little sprout is going to grow up into a big, beautiful head of hardneck garlic. Planting through plastic keeps the weeds down ... important for a plant that's in the ground for almost 9 months. It also keeps the soil warmer, reduces water evaporation and results in higher mounds of good soil for the plant to put out its roots in. The key for me will be to properly dispose of the plastic, which is recyclable. If I do that using the plastic should have no negative affect on sustainability.
A little garlic plant begins its 8 month journey to maturity