Maybe an autopsy to see if something is eating the roots?

tj

Yes, I thought of that, but really, I'm pretty sure I have no voles at all in this heavy clay, though I had them like mad at my old place and they never bothered Rudbeckia.

Maybe work some compost (not mulch) into your soil every year. I have done that in most of our heavy clay soil and it is improving a lot. Areas are more loam now.

Grubs can also attack roots.

tj

Of course I have worked to improve the soil, of course. And grubs can attack roots--but only the Rudbeckia?

Mine seems pretty happy in my rocky clay soil. I didn't amend the soil when it was planted because it was a volunteer from nature. I left it because I thought the leaves were pretty and then started making a flower bed next to it. I think you should try again in unamended soil since it's a native plant. Some natives are a bit sensitive to too much fertilizer and prefer pool soil.

I have no suggestions but now I lwant to try Rudbeckia maxima in my sandy soil :-)

Christie, my soil is still very poor. When I say amended I don't mean I'm pouring fertilizer on it. I use wood mulch and when I cut the prairie grasses back I lay them around other plants and put mulch over them--all to improve soil tilth, not to fertilize. I occasionally use some of the Espoma organic ferilizers around plants that clearly need it--unlike most clay soils, mine is nutrient poor--, but I've never used anything on the Rudbeckia. It's still clay.

I'm completely baffled by their loss. And even stranger, my Viburnum pragense, it's 5th spring, is not evergreen in this soil, though it was and still is just 4 miles up the road in my former place in sandy soil. And this year, the new leaves just won't size up--they're very small and have been that way for weeks. Everything else, all the viburnums and other shrubs are full leafed out.

My soil is poor too. I get excited when I see a plant description that says it likes poor soil. lol

It is puzzling since you didn't move very far. Do you think the people that owned the property before you might have used a lot of chemicals? Maybe a difference in pH?

It would be interesting compare a soil sample from your old place to this one. The new owners might think you're batty if you start digging in their yard though.

I moved from a pocket of extremely sandy, nutrient poor soil to the heaviest clay I've ever seen, also nutrient poor. I brought some plants with me, and some didn't make it, others took a year or so to adapt and some hang in there but don't do much--saddest ones my gorgeous Lycoris sprengeri. The Galanthus really struggle too.

Much of WV is clay--but not as bad as mine. No chemicals--my place is a piece of a larger lot with a house built in the 1920s. In fact, they used to keep a cow on my lot years ago--not that it made any improvement. PH, pretty similar--I did do soil tests.

What is doing well here is quite a long list--Viburnums (except this year the V. pragense I mentioned above) of several species and cultivars, Iteas, Hydrangea paniculata and quercifolia, Iberis, Magnolia virginiana, Physocarpus, Fringe tree, redbuds, Amelanchier 'Autumn Brilliance, Halesia 'Wedding Bells', Siberian iris, Iris fulva, I. prismatica, and Iris cristata, daffodills, Silene regia, Amsonia tabernaemontana, Silphium gracile, Panicums, Andropogon 'blackhawk', Calamagrastis 'Karl Foerster', Sesleri 'Greenlee', Carex grayi, Heptacodium, Monarda 'Claire Grace', Coreopsis verticillata, Agastache 'Blue Fortune' and A. 'Blue Blazes' and on and on.

The Rudbeckia deaths remain a mystery.

Similar situation with me and shasta daisies at my other houses. I've always said any fool can grow a shasta but for the life of me I couldn't get one to survive at my other place, and I tried countless times. I finally took to buying one every year to grow as a potted plant, treating it like an annual and discarding it every year after bloom. Bloodroot didn't like it there, either -- and the strange thing is my next-door neighbor had some and they grew like mad over there...right next door! Here? I have to take the shovel to the shastas every year because they're so vigorous, and the bloodroot are lush and happy as clams.

The point being: Sometimes plants just don't like where they are and up and die on you {shrug}.

Yep, sometimes it's a mystery and remains so. I was just hoping someone would have a genius piece of insight.

My experience is like Porkchop's. Although I have to admit, I don't have the time or energy to try to adjust the soil for any particular plant. I have clay soil as well, although I don't think mine is all that difficult to work with. I am a believer in compost and I'm always trying to add more, but I never have enough. I try not to grow plants that prefer something other than clay. If a plant needs great drainage, there are a few plants I will try to adjust for that. Plant it on a slope or add some gravel deep underneath it. I've done that for Agastaches and Salvias that I would love to grow more of.

I've tried quite a few plants that should have grown in my clay soil and the amount of sun I have and they just don't. If I really like the plant I'll try it in another location and if that doesn't work, there are too many other plants to try for me to feel bad about it for long. :-) If I really really like the plant.... a few years will go by, I'll see the plant again at a nursery and bring it home again. lol And in a couple of cases, I've done what Porkchop has done, use it as an annual in a pot as a last resort.

When you say half of the other died, do you see dead stalks etc on one half and the other half is fine? Is there anything left of the dead plant? If there's nothing that would point towards a late summer droughty? death or voles, if there are dead stalks something happened during the winter... but I'm sure you considered that... what I really wanted to say is that mine did great for a few years and then just vanished. No voles here.

katob, one of the Rm had half die, the other half fine and flourishing. The two others completely disappeared. We did have a late summer drought, but we have had much drier summers and Rm, like other prairie plants, can handle considerable wet and then considerable dry. In any case all three of the Rm had been in the ground for 4 years--this would have been their 5th--with every combo you can think of of rain/drought.

So, are you saying you lost a Rm the same way? Just vanished?

I always thought Rudbeckia were bullet proof. That is surprising.

Yeah. Especially R. maxima, a tough prairie native.

I'm so sorry to hear that they apparently just disappear. They were an important structure in my border--those three big punctuation points and there is no substitute that I can think of--highly deer resistant the main requirement, followed by likes clay, narrow, native.