Growing bulbs out of synch

Mary Sue Ittner
Mon, 23 Feb 2004 07:41:59 PST
Dear Jim,

We had a topic of the week in October where we discussed a little some of 
the bulbs that people had managed to convert to growing in a cycle that is 
different from their normal cycle in their native 
will find some of those posts.

Except for the Ornithogalums many of the other South African genera you 
mentioned: Freesia, Babiana, Sparaxis, Ixia, Homeria are irids with corms 
that are mostly from the winter rainfall areas of South Africa. They start 
to sprout when the temperatures get cooler in the fall and grow during the 
rainy winters, flower in spring and then die down as soon as the 
temperatures get hot. When you buy them from Holland and plant them in the 
spring they often do not grow long enough before the temperatures get warm 
to produce the size of corm they need to flower the next year. Perhaps the 
people who sell these hope you'll just treat them like annuals and enjoy 
them once and buy them again the following year.

One year Diana Chapman wrote advice for many of us who were trying to turn 
around some bulbs in the Northern Hemisphere we had received from Bill Dijk 
in New Zealand. Her advice was very helpful as well as being hilarious and 
she told us to grow the plants in the coolest spot we could and if the 
nights were warm to put them in the refrigerator at night and take them out 
in the morning. I don't know if you could keep yours going longer that way. 
It does seem like a lot of trouble and wouldn't work for things like 
Homeria which can get tall.

I found in turning around some of the South African corms I did better to 
keep them warm until fall and plant them then instead of trying to plant 
them late spring -- early summer and hope to get enough growth out of them 
to produce a good sized corm to survive dormancy. I found the critical 
factor was temperature and I think that is what Lauw was referring to. We 
may not be able to control temperatures in the same way as the Dutch can 
do. But if you were to try to replicate what they do, you'd want to keep 
those Irids growing as long as you could (not exactly easy since most want 
sunshine to do well) and then when they went dormant keep them dry and warm 
as long as possible so they would not think it was fall and time to start 
growing again.

Alan Horstmann in South Africa was going to try to experiment with 
something like this with some of his plants that look a bit the worse for 
wear after a long period of rain. In their normal habitat they would have 
much less rain. So he was going to try to keep them dry longer and start 
them later. I was interested in this because I have the same problem with 
some of the same things. The Ixia leaves of many I grow look terrible by 
the time they bloom in May.

Until you try some of these things you can't really know however which is 
something Tony Avent seems to be finding out. I have found some of the 
Namaqualand species I grow (they may get a couple of inches of rain in the 
winter growing season compared to my average of 50-60 inches) adjust quite 
happily to my surprise. Others really do need to be sheltered from the rain.

I hope this helps.

Mary Sue 

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