Bay leaves are the most efficient and natural cockroaches repellent. Both, dry or fresh bay leaves can be used as cockroach repellent, but still crushed dry leaves in a powder form are most efficient as they release much stronger smell.
Similar to how I picture Command. (the Cooled Conservatories designed by Wilkinson Eyre Architects at the Gardens by the Bay tropical garden in Singapore have been awarded the World Building of the Year prize at the World Architecture Festival in Singap
Singapore's Gardens by the Bay Scoops Prestigious Building of the Year Award at the World Architecture Festival