Tue, 16 Jul 2002 04:14:43 PDT
In a message dated 16/07/02 10:52:34 GMT Daylight Time, writes:
Lauw wrote:

>I cannot see  why: "store them as long
>as possible through the winter so that the emerging bulbs get as much
>light as". This might be valid for summer growing species, but most
>wintergrowers will stop growing as soon as day temperatures rise above
>25° (77°F). 

I must expand on this. I say that the winter / spring flowers need light. 

In the case of Tritonia, a winter / spring flowerer, and where annual corms are produced, top sized flowering bulbs will only be produced if the plants get the required amount of daylength and light throughout their growing period.

Here on the western side of the UK we get most of the depressions that come across the Atlantic, and our winters can be very dark and gloomy in comparison to    some medit countries for instance.

I have found by experimentation and a few years of experience with a many SA winter / spring irids, that the later you start them off in the winter the better they do because bulb quality and size is increased by allowing the plants the higher light levels seen from March, April and May.

Regarding temperature, as you well know, we rarely get 25C in our summers here so there is little problem regarding to temperature dormancy. Indeed to get the temperature I have to store some bulbs inside the house to extent the dormancy period, eg. Chasmanthe.

Hardier winter / spring irids which are grown all year round in the ground here actually do the same thing, they are late to shoot and later to flower. eg. Babiana, Gladiolus and Homeria, these flower in May / June. About a month later than those grown with protection.

Obviously, each species has its own requirements but in order to grow a wide range of bulbs you have to generalise and I do think there is a case for what I'm doing under the circumstances, and I also feel the 'light rule' can be applied to most genera of this type, including Moraeas. 

And yes I agree, it can be very difficult to hold back some of these bulbs and keep them in a dormant or near dormant state.

Too warm and they dessicate, too cool and they grow.

Best Wishes,
Dave (Plymouth UK)

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