Isn't this edge pretty? Trust me, this is very easy to do. All you need are three tools you likely already have on hand.
Baking soda neutralizes the ph in the soil and nothing will grow there. use baking soda around all of the edges of flower beds to keep the grass and weeds from growing into beds. Just sprinkle it onto the soil so that it covers it lightly. Do this twice a year - spring and fall.