It depends upon the parts you plan on using. For chamomile, probably flowers, for instance. Maybe 10 dried flowers per 12 ounces or so? Might be one chamomile plant per harvest per french press. Not sure how many times per year chamomile flowers...

Echinaceae: above ground parts or roots? Etc. So think about the plant, the parts used, and botany...how many harvests will you be able to get per plant.

Very vague I know! Good luck!

Mindy of The Walking Herbalist

I would let the plants become well established before harvesting anything. This means waiting until July or August. Feverfew has been a long lived perennial in my garden. Echinacea is short-lived. Calendula and chamomile reseed easily. Therefore, make sure you have a garden spot where these plants can grown and/or reseed year after year.

Feverfew also reseeds readily.

Echinacea can take a full year to be harvestable, however it will come back every year. Chamomile is almost always just the flowering tops so you'll have to plant quite a bit to get enough to make tea throughout the year, Lavender can be very difficult to seed as it has special germination requirements (Personally I'd just go buy the lavender seedlings instead, much less hassel) Lavender also uses the flowers for tea but the plant produces quite a few flowers so you could get away with fewer plants than chamomile, Feverfew is going to be the same as chamomile, you'll need quite a few to have tea throughout the year, and Calendula is it's own creature, you could probably be fine with 2 or 3 plants. So depending on the plant itself, the species of each you get, the soil/compost/fertilizer you use, and how often you plan on harvesting the plant, also HOW you harvest the plant can all contribute to how much you'll have to plant. My advice is to use this year as a training session, grow what you can and see how it goes, experiment with how much you grow and the placement and you'll know what to do for the following year, it's all going to be trial and error.

Well here's my two cents. I use three candula plants for my personal tea, they take about a square foot each. Would love to have twelve in a four by four space so I could put some up.

Feverfew would look nice growing around the calundula. I don't use it as a tea.

Lavender is an herb that I need as much as I can get. I use the flowers as a vanilla substitute and I have a sweet tooth. My church use to have a wild grove of it that fed me, and someone replaced it with useless flowers.

Lavender cookies, lavender coffee, lavender salve, lavender oil, lavender tonic, lavender fruit jam, lavender cake, lavender oil, and lavender bouquets everywhere. Ah, those were the days. When I had the church's 20 ×5 foot strip of old english lavender it was just enough flowers for me. The more I picked the more it bloomed.

I planted chamomile for the first time this year with the same intention and have been pleasantly surprised with the amount of dried flowers I've been able to save so far. I planted approximately 10 plants covering 2 sq ft of space. I pick the the individual flowers every 2-3 days, which seems to stimulate production. Since it started flowering about 3 weeks ago, I've been able to dry about 2 or 3 cups worth, which I'd say is good for maybe 20-30 cups of tea (?)