Do clothes become impure due to janabah, and do they require washing if some janabah gets on them?

If the garment is not soiled by semen, there is no harm in wearing it and praying in it after performing ghusl. However, if it is soiled by it, it is recommended to wash the wet semen and scrape off the dry semen, as 'Aishah did with the clothes of the Prophet, may Allah's peace and blessings be upon him. This is based on the stronger opinion that semen is pure. As for the opinion that it is impure, it must be washed or removed by scraping.