Capitalize first letter of each word in a dataframe column

You can use str.title:

df.Column1 = df.Column1.str.title()
print(df.Column1)
0    The Apple
1     The Pear
2    Green Tea
Name: Column1, dtype: object

Another very similar method is str.capitalize, but it uppercases only first letters:

df.Column1 = df.Column1.str.capitalize()
print(df.Column1)
0    The apple
1     The pear
2    Green tea
Name: Column1, dtype: object