Christmas trees are being sold all across the city.

But not everybody knows how to buy the right one, or how to care for their Christmas tree.

Greg's Trees owner, Greg Walsh, has been selling Christmas trees to New Yorkers since 1985.

He has eight locations in the city, with stands in Williamsburg, the Lower East Side, Park Slope, Greenpoint and Long Island City. 

Walsh joined Rocco Vertuccio and Shannan Ferry Saturday morning on NY1 to discuss how to pick the perfect tree and how to keep it perfect.