I have been having a serious problem in my garden with slugs. It appears that they are only going after my spinach, but I try to grow as much spinach as possible because of the amount needed to make anything at all. These holes began appearing as soon as my spinach started producing pretty green leaves that my family could not wait to harvest and eat. In an attempt to stop them, and to prevent root rot we are using egg shells.
As we cook, whenever we use an egg we rinse it out and place it in a separate container from our trash or scraps for compost. When we have a large enough amount (a dozen or two) and they have dried, we crush them coarsely and and put a thick layer of shell pieces around our spinach and other greens as a natural boarder against snails.
Snails and slugs won’t cross this border because the egg shells are sharp and will tear their skin and possible even puncture their bellies. In addition to preventing snails from eating our spinach, egg shells are made up primarily of calcium and a lack of calcium is what causes root rot. Recently after heavy rains, we lost several of our lettuce plants to root rot, so we are putting this egg shell boarder all the way around the patch of greens in our garden to prevent losing further plants to root rot or causing the snails to move on to the lettuce instead.
The biggest drawback of this method? You need a lot of egg shells. Along with putting the shells around the greens, we also put them around our tomato plants because tomato plants are notorious for root rot. The way that we do this is to just keep all of our egg shells and cover as much area as possible, doing one more plant or one more length around our greens as we get more. Another solution is to get your friends and family to save their egg shells or find a local restaurant that serves breakfast and ask them to put all of their egg shells in a different trash can that you provide them and you agree to come get them right after breakfast. This is an easy way to score a lot of egg shells all at once. Then as you consume more eggs, you can just add more shells to the places that need them because the shells have broken down too much or washed away. If you ever get to the point where you no longer need egg shells for your garden, just start throwing them in the compost pile or worm farm to add calcium to your compost or worm castings!