1. Stay calm. Chances are that your dog will be fine.
2. Take everything you read online with more than a grain of salt. Seriously. The amount of salt in a large McDonald’s fries, maybe. Even if the person claims qualifications. Perhaps especially if the person claims qualifications.
3. Figure out how much your dog ate. Seriously. Compare this with how large your dog is. If you have a very large dog, he might have to eat quite a lot to do any kind of harm. My dog got into a bunch of fertilizer once. Being the brat he is, he chewed a hole in the bag. He was absolutely fine.
4. If your dog is relatively tiny and/or ate a lot, you need to call a pet poison helpline and/or your veterinarian. Here is a link to a pet poison helpline website based in the US: Pet Poison Helpline | Animal Poison Control Center
5. If your dog did not eat much at all, and/or you refuse to get help, you need to know the symptoms. I hope you still have the container for the fertilizer. Knowing what it has in high concentrations will tell you what kind of poisoning your dog is liable to. For general fertilizer symptoms, here is a link: Pet Poison Helpline - Fertilizer Poisoning in Dogs and Cats
6. I’m not a veterinarian. I am in no way qualified to do anything except give you advice, which you are free to do whatever you want with.

Prima di tutto togli l'etichetta del fertilizzante. Tutti i fertilizzanti sono composti da un carico di ingredienti diversi. Poi porta il tuo cane e l'etichetta al più vicino veterinario/ospedale per animali. A seconda di cosa c'è nel fertilizzante, il veterinario ti dirà cosa fare o non fare.