According to Pink Tentacle,
Each melon is cultivated inside a hand-made acrylic box from a very young age. The vines grow on a wooden trellis so that the melons can be exposed to full sunlight. This allows them to develop nice, evenly colored rinds.
Boui said that he would like to grow melons shaped like gourds and bottles in one year’s time. However, these melons are not as good as the original in terms of flavor as they are not able to fully mature.
Link: Pink Tentacle