Neoprene cables are the perfect cables for outdoor use. These can be laid permanently in water and last for decades. 
Depending on the length, installation and luminaires, different cable diameters are used. 
Small projects for gardens up to approx. 500m2 can use 2x0.75mm2 H05RN-F
For medium to large projects, the 2x1mm2 H07RN-F
For 230VAC connections the 3x1mm2 H07RN-F with integrated DALI control and push the 5x1.0mm2 H07RN-F.
The solder shrink connectors and the shrink tube with adhesive adhere ideally to neoprene and seal perfectly. 
 
The solder-shrink connection technology does not work well on PurPur cables and on TT cables, which are absolutely unsuitable for this.