Hello there!
It should be getting dark starting at approximately 7:30-7:45pm. This is also known as Sunset. This pretty much applies to the United States. in other countries, the time where it starts to get dark is different, due to where the country is located on earth. But if you're still specifically taking about the EST side of the United States Canada, the time the sun sets changes when Daylight Savings time occurs. The recent daylight saving time we had changed the sunset time to around 7:30-7:45. The next daylight savings time that will occur in November, the sunset time would change to around 5:15-5:30.
I hope this information helps you out.