Parallel Regions

Mary Sue Ittner
Mon, 16 Nov 2009 11:42:27 PST

I live in coastal Northern California. My assumption was that besides 
being able to grow bulbs that are native to my area, that I would 
have the best results with bulbs from Mediterranean climates. What I 
have found is that there is a large variation in what constitutes 
these kind of climates and that it isn't just when you get the 
rainfall, its day and night temperatures summer and winter, and soil 
and light conditions in your garden. There are some plants that I can 
easily grow in a pot that for whatever reason, just don't thrive in 
the ground. But this is true of plants that are native to my area as 
well. Examples of the latter are Camassia quamash, Brodiaea 
terrestris, and Calochortus tolmieii. The first two grow naturally a 
five minute walk from my house. The first however is found is areas 
that are seasonally waterlogged whereas my soil which is mostly 
decomposed sandstone drains fairly well and only after heavy rainfall 
is their briefly standing water. I've successfully grow it from seed 
and flowered it in containers, but if any of the bulbs are still in 
the ground where I planted them, I haven't seen them bloom. Brodiaea 
terrestris grows so well in my area that sometimes it is hard not to 
step on it when hiking. It's never thrived in my garden, but does 
fine in a pot.

I thought I might have luck with Australian geophytes if I picked 
ones from some of the Mediterranean areas, but most have dwindled 
away except for some Arthropodium in pots. Plants I planted out did 
not do well in the ground. I can easily grow shrubs from Australia, 
but do best with ones that come from areas that don't get quite so 
hot in summer and have more rainfall. Perth probably has a rainfall 
pattern similar to mine, but temperatures in summer are much much 
warmer. I haven't had great success with Western Australian plants.

The only Chilean bulbs I've been able to grow well also are in pots 
and did not survive the ground test. After I read an article that 
said Leucocoryne needed heat to flower well, I have been unpotting it 
every year and storing the bulbs upstairs in my house where 
temperatures are the warmest in summer and that has yielded more flowers.

Ipheion uniflorum is not a Mediterranean climate plant, but it 
survives/thrives in the ground without summer water on the other hand.

I've had more luck with South African plants in my garden, especially 
ones in the Iridaceae and Hyacinthaceae families, but also some of 
them do better in containers even if I leave them out to be exposed 
to the elements. My assumption would be that the plants from the 
southwestern Cape would be the ones I'd have the best results with 
since the climate there is more like mine. But I am sure there is 
great variation in the habitats and rainfall even in this  broad area 
and some of the species I thought I could grow well haven't done well 
at all. Others are thriving and coming back year after year. On the 
other hand I'd think that winter rainfall South African plants from 
the drier areas would not be happy in my garden with its excessive 
humidity and rainfall in winter and although that probably is mostly 
true, there are some things I grow from dry areas that are doing just fine.

As for the Amaryllids from South Africa, I have become very fond of 
Haemanthus and so far am doing the best with summer rainfall 
species/year round rainfall species than any of the winter rainfall 
ones with the exception of Haemanthus albiflos which grows in areas 
with summer and winter rainfall. I have been able to get Brunsvigia 
grandiflora to bloom for the third year in a row and it isn't a 
Mediterranean species and once had one winter rainfall Brunsvigia 
species bloom, but nothing from any of the others. As for Gethyllis, 
most of the ones I purchased are history and none of the ones I grew 
from seed ever returned. I'm finally getting a few blooms from winter 
rainfall Strumaria and Hessea, but they are in pots. Nerine humilis 
and Nerine pudica are blooming in the ground and they are southwest 
Cape species that I am apparently able to grow successfully, but I 
found that Nerine sarniensis did not do well outside. The leaves got 
diseased in winter and it seems to need more moisture in summer in 
containers that most of my other bulbs so I just leave it in the 
greenhouse year round and water it every two or three weeks when it 
is dormant. It too grows in the southwest Cape. Summer rainfall 
species, Nerine angustifolia and Nerine platypetala on the other hand 
seem to do quite well left outside in containers where they are a bit 
sheltered from my winter rainfall as long as I remember to give them 
occasional water during the summer.

I must confess that I haven't spent enough time really figuring out 
which of the European areas have climates like mine, but am finding 
some of the things I've gotten from Jane over the years are doing 
fine, but I haven't tested them in the garden. Partly it is a matter 
of running out of room and areas where there is enough light since I 
have so much shade in my garden. I suspect some of the plants from 
these regions would do well, but I did learn from Lauw that when they 
get their rain in his area of France which is considered 
Mediterranean is quite different from when we get our rainfall here.

Mary Sue

Mary Sue Ittner
California's North Coast
Wet mild winters with occasional frost
Dry mild summers 

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