A Kiwi mum is calling for two retail corporations to stock more "creative" and "uplifting" clothing designs for boys.

Tash Paterson created the Change.org petition to call on The Warehouse and Kmart to "bring colour into boys' lives" due to the retail giants' lack of clothing variety.

On a recent trip to Kmart, Paterson's nine-year-old son said, "it's like they don't want us to be happy" while observing the lack of colourful and creative clothing designs. 

Paterson says it's becoming increasingly difficult to pick her son clothing from the retailer's uninspired selection of "dark and dreary shades", likening the boys' collections to a "sad afterthought".

"The girls' section is a virtual rainbow of colours with a plethora of inspiring designs and positive sayings," Paterson wrote.

"Even the younger boys' section features an array of creative, bright designs.

"Why is it that the older boys are not afforded the same options."

Over 150 people have signed the petition since it was started three weeks ago, with many agreeing that a more diverse selection of boys' clothing styles should be offered.

"Because boys deserve to have colour," one woman wrote when she pledged her support to Paterson's cause.

"I want my young boys to have the option to enjoy the full range of colours of the rainbow," said another.

In March, an Australian woman was outraged over her local Kmart's poor selection of plus-sized stock. After submitting a complaint, a representative told her they are unable to cater for everyone and it's not "entirely their job to make you feel good about yourself".

The Warehouse and Kmart have been approached for comment.