Particle production

I started my explosion at frame 90. In the Emitter node, key in the Rate. Before the frame you want the explosion to happen (89 in my case), set the Rate to 0 to ensure that no particles are born before that frame. In the frame of the explosion (90 for me), set to your desired Rate, for example, 6,000. Then set the following one or two frames to that same high rate.