Hardiness of ixia and Sparaxis

J.E. Shields jshields@indy.net
Tue, 04 Apr 2006 14:25:59 PDT
Hi Adam and all,

Crinum are a snap.  Plant them deep -- bloom size bulbs about 8" deep -- 
and mulch well in winter.  Do not plant near a terrace (at least not on the 
uphill side).  I grow CC. bulbispermum, x-powellii, and variabile outdoors 
in the ground.  I had three bulbs of one [macowanii X bulbispermum] cross 
survive out of ca. 20 seedling bulbs that were planted outdoors in the 
ground and checked a year later.  Note that although Crinum varibile is 
from the winter-rainfall region of the Western Cape Province of South 
Africa, it is in fact an opportunisitc grower and adapts well to my 
mid-zone 5 climate here in central Indiana.  I have small seedlings from 
crosses like [bulbispermum x graminicola], [bulbispermum x variabile], and 
many more [macowanii x bulbispermum]  growing on in pots until large enough 
to test outdoor in the ground.

I have mainly stuck with South African bulbs from the summer rainfall 
regions and especially the Drakensberg.  Even so, survivals outdoors in the 
ground have been very limited.  One large plant of Kniphofia northiae has 
survived many years outdoors in the raised rock-garden bed.  There is very 
little protection from freezing, but the drainage is excellent.

Other Kniphofia have survived under heavy mulch for a few seasons, then 
disappeared:  citrina, hirsuta, caulescens, and sarmentosa.

Moraea spathulata and other high altitude species from the Drakensberg have 
done poorly outdoors in the ground here.  Some have not survived 
transplanting from the seed trays.  Species you should try 
include:  alticola, galpinii, and huttonii, as well as spathulata of course.

Several Dierama plants from Diana (Telos Rare Bulbs) Chapman survived here 
outdoors in the ground for several years before disappearing, and they even 
bloomed:  DD. dracomontanum, igneum, and latifolium were among these.  My 
own seedlings of Dierama have not survived transplanting from the seed trays.

I have a pot of Androcymbium melanthoides that has survived several winters 
outdoors in a cold frame.  This one should be grown from seed, then 
selected gradually for cold hardiness.  Mine has bloomed for the past two 
summers.  I'm confident that a quite cold-hardy strain could be 
developed.  Last autumn, I chickened out and put the pot in the greenhouse 
for the winter.  I hope I have not screwed it up this by doing this!

Best regards,
Jim Shields

Jim Shields             USDA Zone 5             Shields Gardens, Ltd.
P.O. Box 92              WWW:    http://www.shieldsgardens.com/
Westfield, Indiana 46074, USA
Tel. ++1-317-867-3344     or      toll-free 1-866-449-3344 in USA

More information about the pbs mailing list