The guy who wrote this, Brett James, lives in Liverpool so the planting dates are for that region of England. The dates aren’t the same but all the other info should transfer. If ya want to know the planting dates for the US, go to http://planthardiness.ars.usda.gov/PHZMWeb/ Enter your zip code and find your growing zone. Then look on the back of the seed packets to find out the dates to plant those particular seeds in your zone. The rest is still of the info in the graphic is still applicable.