Space Needed to Grow Feverfew, St Johnswort and Echinacea

I intend to order feverfew, St. johnswort and echinacea seeds. Please send information on how many square feet of space 10 grams of seed of each of the above would require.

Feverfew would require 1000 square feet of space, St johnswort 2000, echinacea 70.