The iron phosphate gets ingested from bait and disrupts the slugs digestion. They starve. I covered the ground regularly through a whole life cycle (I think), since March. The outcome... very little slug damage. I also cut back on over using chemicals broadly. I now use them with a fine focus. The benefit... I found a toad. Toads love snails and slugs. A correlation... probably. Less toxicity keeps the good creatures around.
I will never go purely Green (it isn't realistic for me) but always try to go Greener. I use Sevin Dust as the big killer. I used to dust it or spray it too liberally and found I killed off way too many beneficial insects. I mentioned before I consider Sevin a safer chemical alternative to others in that class. But it is toxic. You can do the research.
I also use wettable sulphur and wettable copper. Both are actually considered organic. Sulphur is more liked. Copper can kill worms, "they" say. Again, use them with a focus. I have been spraying my tomatoes with sulphur because of my belief disease is coming. I usually start in June. I am starting early. As I said the trees around me look ill and its actually been rainy and even muggy.
My tips are this... you can reduce a lot of damage from insects by learning about their cycle of life and disrupt it. And you can prevent diseases or diminish disease damage by striking early.
1. Slugs and Snails get Iron Phosphate starting in March.
2. Sevin Dust gets sprinkled with a focus.
- eggplants in May to kill flea beetles
- peppers in May to kill flea beetles if holes appear
- stems of zukes, cukes, and squashes in May for all kinds of bugs. (stem only where it touches the ground)
- keep Sevin available for other pests
3. Tomatoes, Cukes, Zukes, and Squashes get a weekly spray of wettable sulphur to pre-emptively diminish early blight, septoria spot, bacterial spot, and mildews.
4. All my plants are getting dosed with aspirin as per past blogs. (this is an experiment)
I haven't found a cure for my grapes, they always get something. And my apple tree always gets something. I think I have to use dormant oil spray on my apple tree but always forget. Now it is too late.
It is important you think about prevention and use my ideas (if you want) and other ideas early and wisely.