Iris magnifica, Eremerus himalaicus
Sun, 29 Mar 2009 14:18:02 PDT
On 28 Mar 2009, at 16:39, Jane McGary wrote:

> I think you need to chill [seed of Iris magnifica] AFTER it is planted and
> moistened. This is the typical need of plants from cold steppe regions. At
> least, that is what I do with Junos and it works.

Jane has indirectly brought up an important point for those not used to growing 
bulbs from seed.

Many gardeners, used to the warmth + moisture = germination equation typical of 
annuals, make the mistake of thinking the same equation applies to everything 
else. This mistake overlooks the fact that the annuals widely sold in seed 
packets have been subjected to many, many generations of growth under warm, 
moist conditions, and have evolved to respond well to such conditions no matter 
what conditions their wild progenitors experienced.

However, we bulb enthusiasts aren't growing annuals, and the seeds we receive 
from exchanges generally demand conditions approximating those experienced in 
the wild.

My practice, for the last 30 years or so, has been to soak seed until it is 
thoroughly hydrated, sow in a soil-based compost, and park the pots outside 
where they are exposed to natural conditions, though with protection from rain 
during the winter.

The soak also removes growth inhibitors from some seeds notoriously difficult 
to germinate. Glaucidium palmatum is one such, and some clever people put their 
glaucidium seed in an old sock and suspend it in the toilet tank: every time 
the toilet is flushed, the water is changed. With this exception and a few 
other bad germinators, most dry seed is ready for sowing when it has plumped 
up, usually within a few days.

An interesting exception is the genus Narcissus: I have found that Narcissus 
seed sown in the later winter or spring often germinates the same summer.

It is important to use soil-based compost. Many species of bulbs take several 
years to germinate, during which time peat-based composts will pack down into a 
dense airless sludge.

Though not bulbous, it may be worth mentioning that I hold back sowing 
Lamiaceae (aka Labiatae, the mint family) and Asteraceae (aka Compositae, the 
daisy family) until the weather is warm. Seeds of species in these families 
often respond much like the commercial annuals: warmth + moisture gives fast 

But on the whole I find more success in letting the seeds germinate when they 
will instead of trying to force them to germinate. I am always puzzled by 
reports "I applied GA3 and all my seeds germinated on Labor Day!" What then do 
you do with all the young seedlings to get them through the winter after their 
premature germination?

Rodger Whitlock
Victoria, British Columbia, Canada
Maritime Zone 8, a cool Mediterranean climate
on beautiful Vancouver Island…

More information about the pbs mailing list