It may be done in hiragana as well, especially that れんげ reading (to my knowledge) does not have any other homophones, which means it will be associated with 蓮華. Are you getting a tattoo of a computer font or will you go for calligraphy? To give you an example of what is the difference between calligraphy and printed font (活字) is here you have few works of mine:
花 flower
愛華 Aika (female name which means: love flower)
If you need calligraphy you can send me a PM, I am located in Tokyo.