Reference picture 
Sketch in gouache
Cypress in watercolor in video
Cypress in watercolor - ENGLISH VERSION
Supplies :
Brush : Escoda aquario nº18.
Paper : Canson Héritage rough.
Colors : Cobalt blue (Schmincke), Aussie red gold (Daniel Smith), Winsor red (Winsor & Newton), Burnt sienna (Daniel Smith).
And here you have the finished painting (Click to enlarge) :
