Glads and Romuleas sprouting

Mary Sue Ittner
Thu, 10 Apr 2003 16:26:56 PDT
Dear John,

There are both winter and summer rainfall Romuleas and Gladiolus. When you 
start them depends on whether they are one or the other. Winter rainfall 
plants are best started in fall and summer rainfall plants in spring. That 
is the reason Alberto is always after us to designate in the BX when the 
plants grow.

You may have missed what has been said more than once and that is that many 
of the South African Irids need a change from day to night temperatures to 
germinate properly. I have had much better success with mine since I have 
moved my seed pots to my unheated greenhouse where I am sure they will have 
warm temperatures during the day and cool temperatures at night. I start 
most of the winter growing Irids in October and most germinate a month to 
six weeks later. In my experience Gladiolus seed that doesn't germinate the 
first year rarely and maybe never comes up later. Romuleas on the other 
hand are very different. I have learned from Robin Attrill to be patient. 
If they don't come up the first year I move the seed pot to a shaded area 
outside and leave them. They get water when it starts raining again and 
they often come up the second year.

If your plants are winter growers and they are just now coming up 
(hopefully they have been up for awhile and you just didn't know) be sure 
you keep them as cool as possible and feed them well. They have a tendency 
to go dormant when the weather gets warmer and may not have made a large 
enough corm to survive their dormancy. Unlike Amaryllids I haven't been 
able to keep them going for a whole year the first year.

Of my 33 packets of irid seed from Silverhill I had germination in 24. None 
of the Aristeas came up and two of five of the Lapeirousias didn't come up. 
When we were talking about difficult seeds in December I mentioned these as 
being an ongoing challenge for me. One Micranthus didn't come up and three 
Romuleas species out of eight. I have given up on those last three however 
and will keep those pots for three years. All of the Babiana, Freesia, 
Gladiolus, Ixia, Moraea, and Watsonia seed I purchased from Silverhill 
germinated to some degree.

At least from my experience paying attention to providing a change in 
temperature from day to night has improved my success.

Mary Sue

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