Insect Guard - Controlling the cabbage worm

I have started planting various types of cabbage and one of the biggest problems is the cabbage worm.   I am utilizing organic methods so spraying is out of the question.  The farm that I am using hasn't had any chemicals used in 25 years so the owner does not want me using any pesticides.  The best way to keep your cabbage plants and similar plants such as broccoli, cauliflower, etc safe is to keep the Cabbage moth from laying eggs on the plants.   I am utilizing an insect screen that will keep a lot of the insects off the plants, but it still lets air, sunlight, and water to reach the plants.
I am using PVC pipes glued in a U shape as a frame for the cloth.   This is a cheap way to build supports as a 10 foot piece of 1/2 pvc pipe is around 2.00.      My rows are 34-36 inches wide so so I made the supports 38 inches wide.  I attached the netting to the PVC pics with some clamps that were 69 cents a piece.   There are some pictures of the netting partly installed and completely installed at the bottom of this post..   I am hoping that this will also deter the critters from munching on my plants until they get a little bigger.    I don't mind giving some back to mother nature, but not everything.

Here is a picture of the cabbage moth.

Here's a picture of the eggs

Here's a picture of the worm

Here's a picture of the damage that they can do.

Here are some pictures of the insect guard installed that will protect my plants from the cabbage moth.