That weed barrier has doubled my plant yields - been using it for years. In my opinion it has been the single most effective boost to yields of anything I've done for the plants. I help with compost, lime and fertilizer, but nothing gave the boost like the weed barrier.
It also saves a passle of work - I haven't had to hoe since I started using it!
Started with clear plastic and recycled gray fertilizer bags, switched to the black plastic used by veggie growers. Two reasons - the fertilizer bags took too much work to clean, open and place, and the clear plastic just let the weeds grow underneath.
I put drip tape irrigation underneath the plastic to water if needed.
The theory is that the benefits of the barrier come from the elimination of weeds competing for nutrients, and from moisture conservation. I'm told that 90% of the moisture plants get comes through capillary action from the soil moisture reservoir below, and the barrier prevents this moisture from evaporating, saving it for the plants.
