I know you can't tell me specifically as everyone's conditions are different, but here is the story:

I found a rotty Iris today :(

I swear it was like a cartoon plant death- I was watering and the fan just slowly went over.... over.... a-a-and it's down, Jim. I went to see what was going on and the whole fan fell off when I touched it. Inside what should have been the rhizome was goo exactly like vanilla pudding, about a tablespoons worth. It smelled like "plants"- not at all putrid or foul. I dug it all up and discarded it- the roots were there but they attached to nothing. No bugs or grubs or anything like that. The fan itself looked good with new leaves growing.

This was a 'Penny Lane' that I received from Schreiner's and planted July 20th. It was planted with the top of the rhizome showing and it was in full sun, facing the light- mulched except for the top of the foot thing. When I planted them I mixed in a hand-full of compost and a small dash of bone meal into each planting hole.

Now- I water a lot. Especially new plants. I would estimate that I water deeply and well three times a week when we have no rain and the weather since this plant went in has been hot (90's F) and sunny with very little rain. I water frequently because I have fast draining sandy loam plus very many huge oak and hickory trees that suck up water. I do add a lot of compost top dressing every year and use mulch that decomposes (shredded leaves plus store bought shredded hardwood, buttloads of both) in hopes of improving my soil but I have a big place and the compost only goes so far. I feel like I need to water this often and probably more- for instance I dug fourteen holes today to put in some new plants and the soil was bone dry in each one. It is not wet out there by any means.

The other Penny Lanes I received look good, as do all the other varieties I added this year- a lot of dwarfs that went in earlier in the summer plus all the Intermediate and Standards I put in. But since I found the rot I am afraid I am watering them too often? I would hate to think that it was something I did that caused the rot. And I double especially hate that it was one of my Penny Lanes that was lost as that is the very variety that triggered my whole Iris bender to begin with. Seems that's how it always goes- the one you love the most is the one you lose.

If you have made it this far, thank you so much- I guess I have two questions- 1) was my rotty Iris triggered by my
frequent watering or was it something incubating in the plant itself? Not looking to blame anyone, I know plants die. I just want to understand.

And 2) How often do this years new irises need to be watered going through the fall if I feel like the soil is dry?