I have so many different agastaches. All were purchased locally except for those sent to me to trial in my garden for zone hardiness.

Black Adder
Blue Fortune
Golden Jubilee
Purple Haze
Salmon & Pink
Heather Queen
Summer Love (trial in my garden for Terra Nova)
Summer Sky
Summer Glow
Purple Pygmy (difficult)
Cotton Candy (trial for Terra Nova)

...and probably a few more that I'm forgetting right now.

I'm in Chapel Hill. This is my "go to" variety for my full sun garden for drought tolerance, deer resistance and rabbit resistance.

Here is a link that might be useful: agastaches in my garden

forgot my favorite Navajo Sunset (orange); also Coronado (apricot)

I have Heat Wave and it's returned well this year and getting ready to bloom. The hummers love it. Blue Fortune is a favorite with butterflies and bees and really pops in the garden. I also have Tutti Frutti and although it's a little gangly the hummers use it constantly so it's a winner with me. And all of this with little to no care in mostly clay soil...great plants! I'd like to try Black Adder too.

I bought these new ones at Bluestone's 1/2 price sale. Always need something to stand up to summer sun - I think I remember Tony A's advice that they won't all do well in NC - Is this right. Does this mean short lived? Too much humidity? Wet winters? (Summer Love, Heat Wave, Black Adder)

Is Black Adder perhaps more narrow than usual?

I think agastache does just fine in NC. I didn't lose any agastaches over our very wet winter and I've never lost one in summer so far.

Black Adder is tall, but can be pinched back if you do so early in the spring. Mine is in the 2nd year and remains narrow, but it's a favorite.

All of my agastache varieties receive full sun, all day long. They like well-drained soil, but the (wider leaves, bottlebrush blooms) Black Adder, Purple Haze, Golden Jubilee and Blue Fortune can handle a bit more moisture than the western agastache (narrow leaves, tubular blooms).

Short-lived? My garden is young, so I don't have any plants older than 5 years. My oldest agastache 'Salmon & Pink' is on year 5--one of the first plants in my garden. It's supposed to be a short-lived variety, so I take a cutting in early spring to root for a new plant.

Do not cut back agastache in the fall. Let the stems stand over the winter.

Do not put mulch too close to the plants.

Do not pour water (no sprinklers) on top of the plant--water at the base.

Don't give it too much water after established. If the leaves wilt in the hot part of the day, but are perky the next morning, it is fine. If the leaves are still wilted in the morning, give it a long drink at the base.

There shouldn't be a problem with pests munching on agastache.

Forgot to add that even though there are dead stems standing in the winter on the western types, you'll see green basal foliage. In spring, when the growth looks new, cut off the dead stems.

The wider leaf varieties will die back completely in winter, but I still leave the stems...just like salvias. If you can grow salvias successfully, then you know how to grow agastaches.

Can anyone supply me names of suppliers of Agastache. I order from Plant Delights Nursery, but hope there may be a source of Black Adder that you can supply me with.

Slim pickings now, but several vendors at the Farmers Market in Raleigh had agastache. Pretty sure that's where I bought my Black Adder.

The big blooming vendor in Sandford (which we're not allowed to name) had agastache, that's where I bought my cotton candy and acapulco 'salmon and pink' (which bloomed for 5 months straight). I think I bought Golden Jubilee at Lowes.

All have done well for me, but then I have dry soil (actually lost a few due to the drought). They need good drainage to be happy, and if you have heavy clay you will need to amend the soil or grow them in pots.