Conanthera | The use of hardy/half-hardy/tender

Lee Poulsen
Sat, 27 Nov 2010 13:12:07 PST
On Nov 26, 2010, at 7:59 AM, James Waddick wrote:
> 	I went to read the entries there and was struck by the line
> 		"They are not quite hardy ".
> 	Now what does that mean?. I assume they are not AT ALL hardy here in the midwest, but are they not hardy in Central CA either?
> 	Or do you mean they are 'tender'"?	or demand frost-free conditions or ?

I grow this Conanthera (trimaculata) as well as bifolia and campanulata, here in the southern California coastal valleys area. They are really carefree and flower every year for me without my having to do anything special. I give them no protection. However, it only just gets down to 0°C most winters, and even in a very cold winter such as the one we had 2 or 3 years ago, it only got down to -4°C on two consecutive mornings. This was cold enough to badly damage leaves on some Clivia that happened to be completely exposed to the sky and not near any buildings or walls. None of my Conantheras were protected either and they were unaffected by this freeze, so they can take a little bit of cold.

However, I completely agree with Jim W. about the usage of "hardy", "half hardy", and "tender" without an associated location included in the description. I remember when I was a teenager, before I learned more about different world climates, that I was always stymied by the use of these words in descriptions of plants that I wanted to try growing at my home in Texas. I didn't pay attention at the time to the fact that many of these were from descriptions given in British books for people living in Great Britain. What I did know at the time was that many of the plants that I was already growing often did not correlate with the hardy/half hardy/tender descriptions given in the library books I checked out. And I could tell they didn't correlate with what I knew of their hardiness growing in the northern half of the U.S. It was very puzzling and was almost useless information for me, but I didn't have any other sources of information for some of these plants. (I was particularly perturbed by the term "half hardy". I didn't know what to do with such a plant. Could I grow it? Or would it die in the winter? I couldn't tell.)

I've been on business a lot in the last 4 months in São José dos Campos, Brazil which is just north of the Tropic of Capricorn near São Paulo at about 2000 feet above sea level, but only about 50 or so km away from the ocean. I've always been puzzled by what little I could figure out about the climate in this region from available weather statistics online. It turns out to be a very interesting and basically pleasant climate. I thought that other than being on the humid eastern side of the continent, it was somewhat similar temperature-wise to southern California. However, it turns out to be much milder at both extremes and, from my point of view, you can grow a much wider range of different plants than you can in southern California. I'm speaking of temperatures here, as in hardy, tender, etc. Humidity and annual rainfall pattern are also important for different plant species, but those are different factors than hardiness vs. tenderness. (The most obvious difference being that mediterranean plants will be a challenge to grow here due to the heavy summer rainfall and almost dry winters.)

While we can grow Heliconia and mangoes in parts of southern California, it's not that easy, and you don't get prolific fruiting or flowering. However, in SE Brazil as they call it, mangoes grow everywhere, both as intentionally planted shade trees and wild growing trees that appear to have come from seeds that were abandoned. Right now there are mangoes of all kinds maturing on trees throughout the city. It's kind of amazing to see. And there are spectacular inflorescences of Heliconias of all kinds of species visible as one walks or drives around town. What is amazing to me is that in the winter time however, it is rather cool, very reminiscent of the fluctuating temperatures we can experience in So. Calif. during the wintertime. And yet it can (until recently, in the past 10-15 years, according to Mauro Peixoto who lives in this area) frequently get close to freezing, and even below freezing in exceptional winters. Mauro says it used to regularly frost every winter several times with lows down to 0° or 1°C, with an exceptional freeze of -4°C about once every 10-20 years. And yet the trees are filled with epiphytes, many bromeliads and some orchids, and they're all native (except for the mangoes). Worsleya procera experiences this kind of weather as do a number of Griffinia species. And yet true tropicals won't grow here; it's just too chilly in the winter. (Things like Cacao, red sealing wax palm, and cashew for example. Cashew survives but never fruits. However, pineapple of all things does just fine and I have photos of them fruiting right next to Japanese persimmon trees that are also fruiting with lettuce growing right next to them fully exposed yet not bolting nor becoming bitter in what is equivalent to being almost June in the northern hemisphere.)
So one could say that pineapples are hardy here, cashew is half hardy, and cacao is tender. In SE Brazil.

And I now need to re-calibrate what I thought of as tender and hardy, even in a climate like that of So. Calif.

--Lee Poulsen
Pasadena, California, USA - USDA Zone 10a

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