A tablespoon is a non-scientific but very widely used unit of volume, which works very well in cooking, herbal medicine, etc. It is represented by a capacity of one tablespoon which varies from roughly 15 mL in the US to 20 mL in Australia.
1 If tea is properly stored, it can potentially last up to a year for green and black teas. White tea lasts about six months before it isn't as good in quality as when fresher. Stale tea (or bad tea) will taste flat, as if you're drinking paper.  Glass or ceramic containers are fine provided that they're opaque.
At first glance, loose leaf tea seems more expensive because the price of the bag on the shelf may be $8, and you know at the grocery store there are boxes of tea for $2.50. The box of tea at the grocery store probably has 20 bags of tea, about 12.5Â¢ per cup of tea. The loose leaf tea says 3 oz. As we will discuss below, the rule is to use 2 grams of loose-leaf tea per cup. There are about 85 grams in 3 oz, so there are 42.5 cups of tea in a 3 oz. loose-leaf package. The loose-leaf will be around 19Â¢ per cup of tea, just 5Â¢ more for much better quality. The only thing to stop you now is the convenience of tea bags.