Daphne, many thanks for the added info.
Hopefully you will have plenty of blooms (but no Bloom Out!!!!) a little later

Leslie, thank you! So far no one seems to recognize the twisted rhizome description. I'm not sure if the picture in the AIS blog is meant to illustrate the twisted rhizome or not, but if it is, I might not interpret it correctly, because I don't really see it. Maybe it is a very subtle twist?

Lucy, thank you. In your case it seems cutting the stem was effective.

William, I read that blog from Bonnie Nichols and think she is describing one form of bloom out. She said that it was her first experience with "lightbulb" bloom out, where there are no increases and the roots wither away. Leaving a lightbulb shaped rhizome (I am guessing, pretty much what we have all been calling a potato). I did not see the "twist" she described though. I have had some rhizomes that lose their roots. That pretty much ends them for me as I have zero luck with potatoes.

Leslie, I reread the blog, and I believe you are 100% correct.

So then we basically have to deal with two types of fatal bloom out.

The trials of an iris grower never ends.

At least two. Hate to think there are any more!

I did think about one other common thread on my 3 bloomed out SDB's I have had. They all bloomed much earlier than they should have, by several weeks.

I loosely use the term bloom out to describe any iris rhizome that blooms and has no increases and dies. I have been growing irises for about 9 years and this has only happened on 4 occasions.

1. Silver Streak
I purchased Silver Streak in 2015 and received two large healthy rhizomes which were planted directly in the ground in mid March (early autumn). They both bloomed 7 months later but one bloom was taller and didn't look like Silver Steak. I asked Tempo Two what the other flower is and was advised that they are both Silver Streak. The pale bloom stalk did not produce any increases. The normal one produced two increases. I added some Osmocote around the rhizome of the pale one and made sure it had adequate water through our hot summer and it eventually put out a tiny increase and survived. It hasn't been mature enough to bloom since but I am expecting it to bloom this year. I want to see if the flower colour is washed out again or looks normal. It hasn't produced any increases. I wonder if there is a link between the washed out flowers and the rhizome's struggle to produce an increase.




2. and 3. Rippling River
Rippling River was purchased and planted in February 2014. It flowered that year and produced 2 increases. One of those increases flowered in 2017 without producing any increases of its own. I added osmocote and some nutrient rich soil and eventually it produced a small increase and survived. In 2018, the other increase off the origin rhizome flowered in October. I did nothing and it looks dead. I eventually added some Osmocote in mid January and there is still no sign of life. I wonder if Rippling River is just prone to bloom out in my garden. Interestingly, Rippling River is one metre away from the Silver Streak that almost bloomed out.

4. Chardonnay and Ice
I purchased Chardonnay and Ice in the middle of the iris bloom season last year and received a rhizome with a bud on it. I planted it in the ground straight away and decided to try to get it to bloom because it had three increases and I thought it couldn't bloom out. It produced a small bloom on a shorter stalk and after flowering, all of the increases died. I didn't notice until mid January (2 months after bloom) and I added Osmocote. A month later it produced a tiny leaf on one of its existing increases and then died again.

Robin, sending out a rhizome with a bud on it, seems like very questionable thing to do for a vendor.

It sounds like 'Chardonnay and Ice' put all of its remaining energy into that bloom stalk. Do you remember if the rhizome was covered with soil or not, as I know it is often recommended to plant irises a bit deeper in Australia?

While I definitely never had a fatal bloom out here, I have had irises perform a bit like yours, Robin.



'Can't Touch This' bloomed without a good root system, fell over in the wind and needed to be staked. After bloom, it started producing many increases (a sure sign of stress in many plants), but they wouldn't start growing that summer. The mother had no roots, so could not provide enough for the increases to grow normally. The following year I managed to save a single tiny increase. In a last hurrah I guess the remaining energy went into that increase. The rest all rotted. In a warmer climate I suppose they would have been at risk of drying out instead.

I plant my irises so they are just covered with about 1 to 2 cm of soil over them.

It makes sense that the newly planted rhizome of Chardonay and Ice with the bud struggled and maybe the pale Silver Streak rhizome had problems settling in but Rippling River is a mystery. I think I'll move it somewhere else and see what happens.

thanks robin, with the scorching summer sun in my area, i think i will cover the rhizomes with a little soil as well from now on. especially in the back sw garden.

Daphne ~ I thought that you lived near the beach where it didn't get too hot.

i live about 1-1/2 mi from the ocean. we get a "marine influence". but we are still considered desert? we still get salt in the air especially on our windows ☹️.

When I lived near the beach, it never got very warm in the summer...but that was many, many years ago.

evelyn, depends what beach in california, northern or southern. northern california beaches and water is much colder because the currents flow from alaska, whereas socal is closer to the equator and have warmer currents.

i know when we went to the beaches in norcal, even in the summer, we would bring a windbreaker coverup just in case it was cold. most of the time the summers in san francisco could be "freezing".

although, we are usually a lot cooler in the summer, in comparison to the east counties in san diego. when we do have temps in the high 90's or low 100's. it could be 110 - 120's inland. guess it's all relative?

Daphne ~ I used to live in Inglewood, CA and West Los Angeles as well. There, even though inland, we always got the cool ocean breeze. And yes, morning fog many times. Also in Torrance and Redondo Beach. The summers were cool there as well. It rarely got up to 80°.)Maybe the San Diego area is warmer, being closer to Mexico?)

think so evelyn, with mexico closer. but i do think that the weather pattern has changed drastically since we've moved here 14 yr. ago. it has gotten progressively warmer each summer.

I was thinking the same thing when I moved up to northern California. It did not seem as hot in the summer in the earlier years. And we had a lot more snow and days of hard frost in the winter. There was snow on the ground for months at a time, melt and freeze...dirty snow. It didn't melt until late spring.

This year it looks like I actually might have a problem with potential bloom out in my cold greenhouse with the TB Haunted Heart. Many of the rhizomes planted in the greenhouse are smaller or rescues, which I didn't really expect to bloom this year, but many will still do so. As a result many have fewer increases than what I perceive as normal (as compared to irises outside in the garden).

I suspect the extra long and warm autumn the irises got in the greenhouse is the culprit, overstimulating the rhizomes to bloom, essentially it was like growing irises in a much warmer climate.

I do still hope that Haunted Heart will start growing an increase as it otherwise looks healthy. After all I had a few others that on closer inspection actually have a tiny increase forming, but even so, I think it was interesting to experience first hand how different irises can behave, depending on growing conditions.

I hope it lives William!

Thank you, Lilli.

If Haunted Heart happens to bloom-out, at least I got to see it in person first and that is a lot better than dealing with rot. Haunted Heart is one of those irises that seems to divide people, and I'm not sure if I will love it or not. Replacing it, is not a given.

Well, my HH is still alive, so with a little luck I might be able to share it before too long.