CarolineScott said:Soak the roots in dilute soluble fertilizer overnight.
They do better with good drainage.
I had one come back three years,but it did not flower this past season.
I have a white one which gave flowers this past season. (The first summer).
Do not plant too deep---the crown should be only 2 or 3 inches below soil surface.
They do not like winter wet, so plant on a slope or where you know the water does not sit.
The dried up roots will not grow.
Find nice plump clusters which have a visible, cream, growth at the crown.
I am pushing the zones on this plant in zone 3.
I don't really think we're pushing the zone with growing Eremurus here, Caroline - I just think the zone info that's usually quoted is hooey!
Rix and Phillips in the book "Bulbs" show some great photos of Eremurus in the wild... I suspect the harsh environments to which they are adapted give the secret (if there is one) to the conditions they need - cold is not a problem but they definitely need drainage, as you noted.
I agree with all you've said, other than that I've never bothered soaking the roots. (Also, I've never found roots for sale that were actually breaking dormancy. As long as the roots were clearly not dried out, I figured that was as good as it gets these days. The first ones I bought were potted, so no guesswork there! Unfortunately, it seems the supply of interesting potted perennials has kind of dried up around here since then.
I've had E. stenophyllus growing from a planting that predates 2004 - unfortunately, the area has become shaded and I do find it problematic to move these plants due to the rather brittle roots, so this old plant doesn't bloom any more, unfortunately.
As was mentioned, these plants go dormant after blooming - foliage even starts to die off during blooming - so don't be alarmed.
I kicked myself when I broke off the emerging shoot of E. himalaicus while weeding a couple of year's ago. I saw no sign of it that year but it did emerge the following year and bloomed nicely.
The packaged roots seem to be coming more commonly available around here so hopefully more people will grow them - I think our conditions (dry, good drainage) seem to suit them pretty well!