Delphiniums for the Southeast US?

Murfreesboro, TN(Zone 7a)

I've seen some local gardens with towering, beautiful delphiniums, but I've always heard they will "melt" in the south. Are they hardy perennials, or should I expect them to weaken and fade after a few years?

Wanganui, New Zealand

Hi Terry
Delphiniums generally do not like heat and high humidity together so the further south you go in the USA the more difficulty you have growing them as a perennial.
Whereas in Northern states you should get say 5 years out of them you may only get a year or two in S Carolina. You'd get 25 in Alaska Tennessee will be a challenge. They would need to be grown under dappled shade and their roots kept cool by mulching.
Growing delphiniums in climates where summer highs regularly reach 85 to 90 degF for more than a month or so is pushing your luck.
That said, by choosing the coolest place in the garden and growing more heat tolerant varieties such as Dusky Maidens your luck should hold and the may last 2 or 3 years. We even have regular customers who grow them as annuals in Florida. The trick is to grow them in the cooler months and feed them heaps.

Murfreesboro, TN(Zone 7a)

Good to know! I've grown annual Consoida ambiguas in a fairly shady spot, and they got leggy and bloomed sparsely (We're also plagued by very thin soil over limestone and fairly alkaline pH.)

We moved last May to a new home (just a few miles down the road), so I'm hoping to try my hand again as we get settled in here and begin to garden more seriously.

Wanganui, New Zealand

When you do there's a heap of information about growing delphiniums in various situations here. http://delphinium.co.nz/DelphiniumInformation.htm

Cheers

Terry

Lincoln City, OR

After reading these posts, I now know why my Mom who has a very green thumb, has had no success with Delphiniums. She always planted them in full sun with temps reaching 95 to 100 degrees..will pass this on and maybe she will try again in the shade. Thanks for the information.

Hanceville, AL(Zone 7a)

Countryroads, that is why I can't grow them. I have to settle for larkspurs. Luciee {;^)

Wanganui, New Zealand

Luciee, when you refer to larkspur what species are you speaking of? What grows well for you?

Hanceville, AL(Zone 7a)

I live in zone 7 in North Alabama. I planted a packet of seed store Larkspurs years ago and they have been comming up every spring. I have to keep the white ones pulled up so I won't have all pastels. I like the deep purple ones and the pink shades. Online seed stores carry them. They are kin to delphiniums, and are annuals. Luciee {;^)

Murfreesboro, TN(Zone 7a)

Luciee, I bet they are the Consolida ajacis (or one of a myriad other contortions of that name) - aka "annual larkspurs." That's what I planted in some thin, shady soil and they did okay, but they were pretty spindly. That could have been due in part to the fact I left them to fend for themselves, and we had a lot of deer graze in our yard.....

Hanceville, AL(Zone 7a)

Mine are always spindly. I do not mind, as they are pretty hardy here. Luciee {;^)

Wanganui, New Zealand

Sounds like the annual species - and can just imagine them flowering messed in semi shade. Do you have images?

Hanceville, AL(Zone 7a)

No, no images. Luciee {;^)

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