So I didn't do a great job sticking to this prompt as I decided to make their whole outfit a rainbow rather than just the cloack but I'm still pretty happy with it.
Giving them a bright green mohawk made me really happy. I also like how the colours stick out all the more for the brown field behind them.
Not everyone apprecaites seed gifts that grow into awesome colourfull crops so the Rainbow seed sower rushes around with their bag in order to bestow their gift on many a farmer, weather they like it or not.