I think adding {-en} or changing the vowel into an “Umlaut” is used even more frequently.
Examples:
Blume-Blum{en} Haus- HÄuser
Flasche-Flasch{en} Mann- MÄnner
Tür- Tür{en} Ofen- Öfen
Generally, German plural forms can have the suffixes -n/-en, -e, -r/-er, -s. Sometimes, a word gets a suffix AND the vowel changes (e.g. Kuh- Kühe; Land- Länder). {s} is used for example with Foto-Foto{s}, Kino- Kino{s}.