I've always air-dried herbs, so I can't help there.

Another thing people say is that herbs do better in poor soil, with little or no fertilizer -- too much fertilizer will lead to more leaf growth, but also less concentration of the flavors. Could this be the problem?

Hey!According to all the info that I have found,the best time to pick any herbs for drying is; MID-morning;that is when the oil content is highest,before the afternoon sun has had time to dissipate the oils into the air.This to me,means between 9am and 12pm-I usually do it between 10am or 11am.
Also,the leaves have to be bone dry-no dew or raindrops.
I found out, too,that if you're harvesting for storage, the time of harvesting makes the biggest difference,which is RIGHT BEFORE FLOWERING of said herb.At that point, the plant's cells have the most oil in them for the full aromatic quality.
I did do alot of air drying(and still do think it's best) until I found out how to dry certain herbs in the microwave! That works great for mints and you would'nt believe how fabulous parsley does!(keeps colour beautiful).
I would find out more about that dehydrator you've got...I wish I had one!If I run across any info,I'll post you back.I hope I've helped you in some way..I love making my own herbal teas! Good Luck to ya!,CJC

As Caren says, there are optimum times for harvesting certain plants.

But in my experience, dried mint loses its flavour on drying no matter when it's harvested or how it's dried. As with chives, which end up tasting and looking like hay.

Why not freeze your mint instead? You'll get more flavour that way, and it will retain its colour.

I found spearmint taste the best fresh. I see no reason to dry mint. If you have to in order to have it anytime Then I would freeze and vac. seal to keep the moisture in the leaves. I live far enough south I don't need to freeze anytime.

Usually things that are dried fast will have the best flavor. I use the Ronco here and have dried many things including peppers, grapes, and potatoes. It may be the mint strain you used is not suitable for drying or made into tea. Some mint teas use blends of different mint leaves, just like they use blends of tea leaves. If its stored in an air tight container it can still lose flavor and color. I dry dill weed and its crumbled and placed in a Ball canning jar with lid. I use a Food Saver system and the jar adapter to pull a vacuum on the jar and its contents. This helps to keep the dill flavor, color, and aroma very fresh. Its now almost two years old and looks like it was dried last week.

How would you make tea out of frozen mint? Just infuse it in hot water for a few minutes?

I don't think it is your drying process, I think it is your mint variety. Apple mint, to me, doesn't have much flavor. Black-stemmed peppermint is the most pepperminty of the mints. If you dry it well, it will still be wonderfully pungent. Kentucky Colonel spearmint is wonderful for the spearmint taste. You will be amazed at the difference when you grow your Mitcham's black peppermint!

Does your dehydrator have adjustable temperature? I've found that drying over a lower heat on my Nesco keeps the dried leaves nice and green-- higher temperatures on delicate herbs don't do the flavor any favors. If your leaves are brown, the temp may have been too high.

Also, and forgive me if this seems like too basic a question, but how much of the mint did you use when brewing the tea? Maybe you just need to add more to the cup? If you're crushing the leaves incompletely before brewing, they can take up more volume and look like you're adding more than you really are. Also perhaps a longer brewing time is required? Depending on how finely you've crushed the leaf before brewing.

I dry and use a LOT of mint, including apple mint. Not enough room in the freezer for all I go through! Though I do use that technique with cilantro, basil, chives.

The garage sale ronco doesn't have adjustable temp, but I did have the vent all the way open so maybe that was just too fast. I crushed up the dried apple mint leaves enough to fill a large tea ball (about 2 T). Tasted like 'hay tea'. I grew the apple mint because someone told me it made great tea, but maybe I'll have to use it fresh or frozen. The new plants (mitcham black) seem alot more pungent. These have all been great comments:)

The Ronco dehydrators have just a low wattage heater element at the bottom. No fan, but instead holes below and above the heater for the proper air circulation through natural convection. No temperature controls either. Its very basic and really doesn't need much more as to fancy features. I dry all my herbs in a Ronco and it can dry very thick sweet peppers in about 2-3 days.

I use a food dehydrator and air-drying on screens depending upon the type of plant being dried. I've found that even on the lowest temperature setting (and my is adjustable) that it is just too hot for some plant material. Lemon balm, a mint relative, did not dry well in my food dehydrator. It was just to delicate for the dehydrator. It seemed it got too "cooked" so I air dry that. But others like sage, thyme, chives, and more work just fine in the dehydrator. Do your own side-by-side taste tests with your harvests this summer. Just use small amounts and determine what is the best method for the herbs you have.

FataMorgana