Particle effect on collision?

This is a simple question. I did it a couple of times already, don’t know why I can’t get it done now…
I made a particle effect, I want this to get played when the player collides with the platform.
Here’s what I’ve done:

public class StartingPlatformFall : MonoBehaviour
    //public GameObject smoke;
    //public GameObject spawn;
    public ParticleSystem smoke;

    private void OnCollisionEnter(Collision collision)
        if (collision.gameObject.tag == "Player")
            //Instantiate(smoke, spawn.transform, Quaternion.identity);

What am I doing wrong?

Is the player set to have the tag player, and its collision shape not set to trigger? Another thing to check is if either object involved in the collision has a rigidbody.