Database column length for a Java property type 'String'

[SJ]

I am using Jasypt with Hibernate to implement encryption.

Let's say I have a property: String firstName;

Table column is created as: FIRST_NAME varchar2(255).

So what should be the maximum length of the plain text that can I enter into 'firstName'?

To accept 50 characters for firstName property, shall I give the max length for FIRST_NAME column as 100 or 150.

What should be maximum length of the column in database for property of type 'String' that is encrypted with Jasypt?

Thanks in advance!!!!