Any physical Thing is a smart object, if it is embedded with sensor(s), actuator(s), a microcontroller and a low power radio. More often these components can be fabricated in chip, as small as the size of a human thumb finger. The main vision of "Web of Things" (WoTs) is to realize connectivity of the Web to billions of such smart objects. Applications can be built on top of standards like IPv6 over Low Power Wireless Personal Area Networks (6LoWPAN) at the L3 layer and IEEE 802.15.4 at the L2 layer of the network stack. Some of the popular applications include smart metering, building and home automation, healthcare, asset management, environmental mon itoring and industrial automation. One of the main challengesfor application developers is interoperability among the services provided by smart objects of disparate environments. This paper deals with interoperability at the application layer. We present an approach using the REST principles, for smart plant-watering application. The proposed approach can be adapted to any kind of applications involving smart objects. The paper also specifies an efficient syndication algorithm for event notifications from Things. We empirically show that our proposed approach achieves interoperability as well as performs efficiently.