(Image from: https://hudsonvalleyseed.com/products/gigante-ditalia-parsley?_pos=1&_psq=gigante&_ss=e&_v=1.0)
Growing Instructions for Gigante d'Italia Parsley:
Sow indoors 8 weeks before last frost, or direct sow from around last frost until 3 months before first fall frost. Be patient: parsley is a slow germinator but a fast and easy-to-grow plant once up. Parsley prefers full sun but is tolerant of partial shade. Harvest large outer leaves and allow new inner leaves to mature for continual harvest. In temperate climates it is biennial; with the protection of a cold frame or snow cover, it comes back each spring and can be harvested for about a month before it goes to seed.
(from Hudson Valley Seed Company website)