When the dew fell on the camp at night, the manna would fall with it.

Exodus 16:13
That evening quail came and covered the camp, and in the morning there was a layer of dew around the camp.

Exodus 16:14
When the layer of dew had evaporated, there were thin flakes on the desert floor, as fine as frost on the ground.

Numbers 11:8
The people walked around and gathered it, ground it on a handmill or crushed it in a mortar, then boiled it in a cooking pot or shaped it into cakes. It tasted like pastry baked with fine oil.

Numbers 11:10
Then Moses heard the people of family after family weeping at the entrances to their tents, and the anger of the LORD was kindled greatly, and Moses was also displeased.

And when the dew fell on the camp in the night, the manna fell on it.