So we all know that herbs can benefit us by way of a ‘tea’ or, more accurately, infusion. “Tea” is actually meant to refer to the use of the tea leaf (camellia sinensis), which has wonderful anti-oxident benefits. An “Infusion” (or tisane) is a hot-water infusion of other plant material (herbs or fruits) and can refer to all sorts of wonderful combinations and blends.
An infusion of delicate flower material, such as chamomile, need only be done for a relatively brief amount of time in order to reap the rewards. Medicinal infusions of hardier herbs should really be done with a LOT of herb (1 oz) for a long time (4-8 hours or overnight). A little tea bag with nettle leaf in it, steeped for a few minutes is nice, and it certainly will impart some of its nutritional goodness to you, but to really have an effective, therapeutic result, you need to steep a lot of it (1 oz equates to about 5-7 Tbsp) in a quart of water (a mason jar will do).
Again, it’s kind of a question of what you’re aiming to do with the herb! But nourishing, green infusions steeped for 8 hours are such a boon to your systems and can do transformative work over time when taken consistently and persistently. My personal favorite daily tonic is one with red raspberry leaf, oatstraw, spearmint. Red Raspberry is high in tannins, has lots of vitamin and mineral content, and is tonifying to the uterus (which preceeding or following childbirth is a very good thing); oatstraw is nourishing to the nervous system (help!); and spearmint is helpful for digestion and also tastes good! Simple infusions of nettle, oatstraw, red clover leaf & flower, or alfalfa are all nutritious and highly beneficial.
Herbalist Susun Weed has a great article for making herbal infusions found in her resources. She includes detailed information on what to do with various types of herbal matter, including barks, roots, berries, leaves, and flowers. I hope it is a great resource for you!