There are two types of chamomile that you can grow: English/Roman and German. English is a low-growing/ground-cover perennial, while German is an annual bush.
Start your seeds indoors 3-4 weeks before the last spring frost date or you can start them in the garden in early spring when all danger of frosts has passed. Indoors, use a seed tray with a good potting mix, outdoors, pick a spot with good drainage and partial shade to full sun (more sun = more flowers). In both cases, scatter your seeds across the top of the soil and lightly cover with cardboard or your hand and lightly tamp down the seeds. Water in the seeds with a mist sprayer. When seeds are 1-2” tall, thin to 2-4” apart. If starting indoors, be sure to transplant before you see blooms (can be as little as 6-8 weeks), as they do not like to be transplanted and can be stressed more easily. Harvesting can be done as soon as blooms occur. Flowers are great for pollinators, but you’ll want to harvest flowers before they are spent if utilizing them for essential oils. To keep the plant producing, stagger the harvests. Harvest the flowers in the morning, after morning dew has just dried. Flowers are harvested whole (clip the stem at the base of the flower head) and then dry, in the sun, a dehydrator, or a warm oven. Once the flowers are fully dried and cleaned of any lingering bugs, they can be stored for about a year for teas or essential oils.
Leave some flowers for pollinators, and some to go to seed for harvesting and replanting the next year.