Step 6: Attaching the plastic sheeting
Plastic sheeting can be purchased at most hardware stores, such as Lowe's, Home Depot, or Menards.
4 mil plastic sheeting
I like 4 mil plastic sheeting, because it lets in more light. However, it will only last about 1 season out in the weather. The plastic sheeting can be reinforced by laying down strips of white duct tape - ribbing the greenhouse.
6 mil plastic sheeting
This thickness is very durable and is what I chose for this greenhouse. However, it lets in less light than the 4 mil sheeting.
Depending on your growing zone, you may need to insulate your greenhouse. This can be accomplished with 2 layers of plastic sheeting with 1" size bubble wrap in between each sheet.
Measuring and Attaching the Plastic
Measure the plastic sheeting to about 9 feet long. Any extra sheeting can be used to hang over potted plants next to the garden box. Use a pair of scissors to poke holes in the sheeting for the zip ties.
BEFORE poking the holes, attach white duct tape to reinforce the hole.
Attach plastic with the zip ties, but DO NOT pull the zip tie tight. If the zip tie is pulled tight it can cause tearing.