Getting through the first summer, an example

Jim McKenney
Wed, 03 Mar 2004 07:41:12 PST
I have a general observation to make with regard to summer dormancy in
summer humid areas. I have attempted to bring some summer dormant iris
(oncos and onco hybrids) through our humid, hot summers by digging them and
storing the dormant rhizomes under cover but otherwise in the open air in a
shaded place. Something very unexpected happens: these plants, which endure
severe drought in nature, shrivel up and dry out. Some frits seem to show
the same response here, others don't.

With the iris, bringing them into the air conditioned house seems to work
better; the rhizomes remain hard and ironically don't dry out. 

This makes me wonder if the humidity isn't inducing the plants to open
their stomata and lose water - water which is not replaced by a dormant or
non existent root system. 

Is there a plant physiologist out there who can explain this better? 

Jim McKenney
Montgomery County, Maryland, zone 7, where my stoma is getting stuffed with
donuts right now! 

At 08:00 AM 3/2/2004 -0800, you wrote:
>Dear Joe,
>I keep hoping that people from areas with hot humid summers will respond to 
>Joe's request for help. Perhaps Alberto has done that privately as I expect 
>Argentina might qualify, but we also have people on this list from the 
>south. But maybe they grow things from summer rainfall areas?
>I'll take a stab here, but still hope others will come to your rescue. We 
>had a discussion in June last year on Bulbs for Texas with a few people 
>responding to what they had found they could grow successfully:
>I think it may depend on what winter growers you are growing. There are 
>some South African Irids winter rainfall species that grow very slowly and 
>that first corm is really tiny so they could be problematic. Others like 
>some of the Sparaxis and some Ixias grow relatively fast and would form a 
>corm that could be stored easily dry until the next season. I used to store 
>bulbs in brown paper bags in drawers in my house in a hotter part of 
>California quite easily. This is frowned on so I was surprised to hear in 
>South Africa that a few others found this worked too. Others talk of 
>turning pots on their sides so they won't be rained on or growing in 
>mediums (like sand) that are less of a problem for rot. If you grew some of 
>these in containers plunged in the ground in nesting containers you could 
>dump them out after they died back and store them dry inside and put in 
>some summer growing bulbs happy in Houston in that spot. I am sure that you 
>could grow successfully some of the winter rainfall Irids if you treated 
>them this way. Friends in Arizona have found some of the corms I sent them 
>(Homeria type Moraeas, Freesia alba to name a few) have thrived. I wish I 
>could remember what all they were. It isn't as humid there, but they do get 
>summer rainfall and it is very hot.
>I have found with some of the plants I've grown from seed in the 
>Hyacinthaceae family  like Ornithogalum and Albuca that some of my 
>seedlings did not go dormant the first year. I was uncertain what to do 
>with them. People often grow Amaryllids the whole first year successfully 
>so I tried keeping some of them going. This has been a mixed thing for me. 
>One Ornithogalum I keep watering stays almost evergreen. I planted some of 
>them out since they were multiplying rapidly and in my dry summers they go 
>dormant in the ground. In fact I thought they had died until I saw a few 
>growing and blooming last summer. Others I kept growing on that first year 
>skipped the following year altogether almost like they wanted a dormancy. 
>Recently an Ornithogalum that I had grown from seed and kept on growing had 
>all the leaves die. I thought it was our "ark building" winter, but about a 
>month later new leaves have come up so now I am wondering if it would have 
>been better to force dormancy on some of these.
>Anyone else have suggestions for Joe? Tom Glavich grows a lot of Albucas 
>and Ornithogalums in Southern California. Maybe he will tell us what he 
>does that first summer?
>Mary Sue
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