How Much Seed for Half Acre of Lobelia & Allheal?

How much seed does it take to plant a half acre of lobelia (Lobelia inflata) and allheal (Prunella vulgaris)? If I buy seed from you will it come with some instruction about planting?

For Prunella vulgaris you need 2 grams of seed for 1000 plants or about 40 grams for a half acre. Here we mean indirect sowing: that is, sowing in a seed flat or seed bed and then transplanting later to the field. For sowing direct to the field you would need much more seed; but, we don't recommend direct sowing. For Lobelia inflata you also need 40 grams for a half acre.