I had some hostas in Davis...

“I had a farm in Africa at the foot of the Ngong Hills.” 

One of my favorite movies, Out of Africa, begins with these haunting works, spoken by Meryl Streep's aging character Karen Blixen as she remembers her life in Kenya (then British East Africa).

“The Equator runs across these highlands, a hundred miles to the north, and the farm lay at an altitude of over six thousand feet. In the day-time you felt that you had got high up; near to the sun, but the early mornings and evenings were limpid and restful, and the nights were cold.”

This post is nowhere near as fascinating as Blixen's remembrance of a life and love lost long ago (a real story, not fiction), but my lament is similarly wistful.

I had some hostas in Davis not far from Interstate 80. They grew happily in the backyard when I first planted them, but they struggled in the summer heat. Our winters were so mild, they weren't able to spend enough time in dormancy. As a result, they were smaller and weaker when they came back the following year. And the year after, most of them didn't return.

Original batch of hostas in the backyard (photo taken on May 1, 2009)

The exception was ‘Sagae’, shown below. It hung in there valiantly for three years. But finally it, too, succumbed.

Hosta 'Sagae'

I was able to rescue another favorite, ‘Orange Marmalade’, by taking it to my in-laws in the mountains of far Northern California, where it's still alive today.

Now, six years after the start of my Great Hosta Experiment, I have two hostas left. Since they come back year after year, it's safe to declare them survivors. The first one, ironically, is a freebie I got with my original order (see first photo above). It was a tiny thing, just a starter plant, but it has turned into a real beauty. Appropriately, its cultivar name is ‘Climax’. It looks like it will forever be the climax of my hosta-growing efforts.

Hosta 'Climax' surrounded by Japanese forest grass (Hakonechloa macra)

The second one is ‘Sum and Substance’. I bought it in a 4" pot at a local plant sale. This is one of the largest hosta cultivars, at least in climates where hostas thrive. In our backyard, ‘Sum and Substance’ is about the same size as ‘Climax’, certainly nowhere near its potential. With more fertilizer and water it would get bigger, but I don't have any extra water to spare. Still, I like it just as it is; it provides a nice contrast against the variegated shell ginger (Alpinia zerumbet ‘Variegata’) and the other plants in this spot.

Hosta 'Sum and Substance'

Hosta 'Sum and Substance'

But my two hostas pale in comparison to Portland, OR where the next three photos were taken. Just look at that lushness! I don't think it will ever rain enough here in the parched Central Valley of California for us to experience anything like it.

Joanne Fuller's garden, Portland, OR

Linda Ernst's garden, Portland, OR

JJ De Sousa's garden, Portland, OR

So why don't hostas do well in mild-winter climates? Like many other perennials, they need a period of dormancy in the winter. Dormancy is induced by low temperatures. According to the Plant Delights website, most hostas need at least 30 days below 43°F. This is a genetic requirement, based on where each species originated. You'd think this requirement would be easy to meet, but in our zone 9b climate, we just don't get 30 solid days (= 720 hours) of temperatures below 43°F.

There are some hosta species from areas with warmer winters. Supposedly, they have the best chance of surviving long-term in a climate like ours. Most of the hostas I originally ordered were such cultivars, but it still didn't make any difference.

Another issue is water. All hostas are from areas with high rainfall. According to The Color Encyclopedia of Hostas, they need about 1 inch of water per week while actively growing. There's simply no way I could meet this requirement in our Mediterranean climate where it doesn't rain between May and October.

Postscript: 

I found the receipt from my original hosta order dated September 2, 2008. These are the cultivars I bought from HostasDirect in Roseville, Minnesota (they shipped very nice plants, I should add):

‘American Sweetheart’
‘Aphrodite’
‘Fragrant Bouquet’
‘Fried Green Tomatoes’
‘Guacamole’
‘June’
‘Orange Marmalade’
‘Sagae’
‘Stiletto’
‘Striptease’
‘Sun Power’

Plus ‘Climax’, which came as a freebie.

That was $120 worth of hostas.

‘Orange Marmalade’ lives on in my mother-in-law's garden and ‘Climax’ is doing well in mine, but all the others are long gone.