American Fritillaria

Jane McGary
Mon, 04 Sep 2006 16:52:44 PDT
Paul Cumbleton asked about cultivating the American
>Fritillaria, especially pot cultivation under glass.

I grow all the American species and quite a few of the Eurasian ones (not 
including those of the Far East, most of which I have been unable to obtain 
from seed). The literature and seed exchange of the AGS Fritillaria Group 
suggest to me that the American species don't set seed as well in the UK as 
here, and in discussion with a British grower, I suggested that low light 
levels during their winter growth period might be at least partly to blame. 
The British, brilliant as they are in growing almost anything, can't do 
much about their latitude.
Paul asked specifically about:

Watering - approximately when should you start in the fall? (We usually give
>their first drink around the start of October, depending on temperatures at
>the time)

That's about when I start watering mine, but I match the watering to the 
onset of fall rains on the Pacific Coast, so it may be more "natural" for them.

>Dormancy - do you keep totally dry or slightly moist?

I keep them totally dry but they aren't desiccated because the pots are 
large and are plunged to the rim in a medium that sits on the ground in 
bulb frames. When I lift the pots in late July or August, they are faintly 
cool toward the bottom.

>Hardiness - are all truly hardy or should any be kept frost-free?

I think you could consider them "truly hardy" in England, where winters are 
warmer than mine. I have not lost any in the frames when the air 
temperature went down to about 20 F, but overhead protection makes a big 
difference. And many of them are intolerant of excessive winter wet -- the 
inland and alpine ones experience a dry winter under snow. Fritillaria 
striata has had some winter damage here inside the frame, causing it to 
produce deformed flowering stems that year, but the bulbs were not harmed. 
F. liliacea, the other candidate for tenderness, seems unstoppable.

>Compost - are any fussy about pH, and do any require something other than
>the usual types of free-draining bulb composts?

No, I don't think any of them are fussy in this regard, and it's quite 
false that some require heavy clay (adobe). The pH of my mix is probably 
about 6.

>Light - do you grow in full sun or do any require a bit of shade?

I grow them all in full sun (or as much as is available in Oregon in the 

>Feeding - comments??? (more a bag of worms than the other topics!!)

Like all my other bulbs, the frits get one liquid feed ("root and bloom" 
formula) in fall and three in winter through mid-spring. I don't add bone 
meal because it attracts animals.

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