When "Updates Pending" displays in your app, this means that your garden is temporarily disconnected from your network, and the app has saved updates to be made once it is reconnected to your network i.e. turn on light, update water level, etc. You may not be able to control your lights or make changes in the app at this time.
SmallGarden will automatically try to reconnect whenever this happens, however if it persists, simply conduct a "Power Cycle" by unplugging SmallGarden for 10 seconds, then plug it back in. Your SmallGarden should reconnect shortly after and the "Updates Pending" status should disappear in the app.