In 1 Corinthians 3:6, Paul planted the seed. What did Apollos do?

Answer: Watered it

"I planted the seed and Apollos watered it, but God made it grow" (KJV: "God gave the increase").

“What then is Apollos? And what is Paul? They are servants through whom you believed, as the Lord has assigned to each his role. I planted the seed and Apollos watered it, but God made it grow. So neither he who plants nor he who waters is anything, but only God, who makes things grow.”— 1 Corinthians 3:5-7 (BSB)