June 4, 2015


Oenothera caespitosa ssp/ exima proves that not all Evening Primroses are aweful. This alpine is planted in one of the troughs that I keep desert and steppe plants in, as it seems to appreciate the sand and rocky dryness.

I find it so  fascinating that the few plant explorers who are still out there looking for new plant species, continue to find new undiscovered or rediscovered plants. Even though we must clearly be reaching the bottom of the barrel, there are many genus and species which still need greater recognition, or let's say - discovery by the big retailers, or by the large, Dutch propagators and distributors. The fact is, most plants whether they are good performers or not in the garden, never make it to the shelves of big box stores and nurseries for no other reason beyond the more tactical ones on shipping size (too tall for shelves or too large for containers when the bloom, or in particular, a resistance to bloom at the right retail time - a big limitor in a market where a majority of people are entry-level gardeners unfamiliar with what plant they are buying.

Oenothera caespitopsa ssp. exima - The Tufted Evening Primrose
I should warn you that there is a bit more botanical Latin in this post than usual, but try to bear with me, as few of these plants have common names, and if they do, they are too similar to related species and you are more likely to get the wrong plant if you go to a nursery. Take the genus Oenothera for instance. Like Oxalis, its a genus which can offer both weedy and invasive plants that can be a real bugger to exterminate from your garden, while the same genus can offer some real, garden treasures. I am only focusing on the treasures here.

Oenothera caespitosa ( Eee-noth-thera  sez-pit-TOE-sah) is a precious, alpine verision of the more weedy cousin's we have all tried in our gardens. This is not common Evening Primrose ( and by the way, it's not even slightly related to primroses no matter what eBay says.). This one is best for our Western dry gardeners, or in a trough, which is where I raise mine. It's a xeriscape plant that more of us should be growing. A native North American with giant flowers that attract hawk moths at night.  Potted in sand, gravel and a nutritionally weak clay, this Oenothera has a flower which is so out of scale to the plant, that it can be shocking. Let alone it's perfect form - like a Trefoil Girl Scout cookie, I'd say, except a bit larger. My flowers are about 3 inches across.

Oenothera caespitosa is common in much of the West, but east of the Rockies, it is rarely seen in gardens. One can grow it without a drought however. Just plant it in a sand-filled trough or deep pot.

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Raised from seed collected in South Africa, this precious small bulb is an annual bloomer for me - kept in a bulb pan in the greenhouse, it blooms ever June - Freesia laxa.
 Freesia laxa
This post is quickly becoming a bit of a taxonomy lesson, albeit a confusing one at that, but plant species are continually being re-evaluated by botanists and those who study various taxa - and so it goes with one species of what I had originally acquired as Lapeirousia laxa, which over the past ten years had required a label change to Lapeirousia cruenta, Anomatheca cruenta, and Anomatheca laxa until the taxonomists landed on Freesia laxa - what ev's, I like making labels.

Bulbs, or I should say 'geophytes' as Freesia is technically a corm and not a bulb, are ridiculously easy to raise from seed. I really wonder why I don't raise more South African bulbs from seed ( no probs, I really raise enough for most humans!). They generally bloom within 3 years, and once they do, the pots seem to get better with each passing year. This is one species that goes dormant in mid summer, emerging once again after a long dry period in the greenhouse usually around February.

This selection is pure white, yet according to the Pacific Bulb Society Wiki, is most similar to a named selection Freesia laxa 'Joan Evans', but this pot looks more like the all white form of Freesia laxa. It was purported to be wild collected seed.

The floral parts do provide a hint to what family this plant comes from, or at least, close enough to the family (hint - Monarch's anyone?).

Cynanchum ascryfolium
First off, bad name - great plant. Second off - scary genus ( some Cynanchum species are terribly invasive, but--not this one.  You are really getting your botanical Latin workout today. Cynachum ascryfolium is one of those plants that looks pretty unexciting when viewed in a photo, it's jost not that photogenic I guess, but when viewed in the garden? Take my word, it's spectacular.

Nice, tight grower, healthy and sturdy, clouds of small white flowers and best of all - it's a great performer - I mean sturdy, not invasive and easy to grow. Not that I am an expert or even that familiar with this plant, as I just divided my first clump which I recieved from a friend a few weeks ago (he recieved his from nursery woman Ellen Hornig years ago), and given out extreme drought and heat - it didn't wilt at all. He said that it was one of his favortie plants, and I can see why. Today, all three clumps are dense, full and bright with flowers just weeks after I divided it.

Since I am new to this plant, I had to research it a bit, but there isn't too much information out there. Some sites tell me that it is a relative from the milkweek family, actially, more acurately it is placed within the family Apocynaceae - still, a few books still place  the genus Cynanchum within Asclepiadaceae, but Asclepiadaceae is properly treated as a sub-family within Apocynaceae -( I know, right?) - always a good fact to chat about at the lunch table).

Cynachum ascryfolium makes a nice filler for a perennial border, or in a wild, more natural garden. Planted in groups, it even looks better. Think of it as a white Amsonia-like plant, almost shrub-like, but it dies back to the ground every winter.

Regardless of where all of this taxonomess nets out, it's a bit interesting that Apocynaceae is a plant  family which contains mostly tropical plants, which explains why I rarely come across it with writing about garden plants in New England. I do grow many of these plants though, but they are more likely to be found in containers in my greenhouse, such as Plumeria, Nerium (oleander), Pachypodium and Allamanda. Out in the garden, there are a couple of familiar members however- such as Vinca and Amsonia. Most of the plants in this family have milky, white sap not unlike the milkweeds.

More interesting though is what the common name of Cynachum ascryfolium reveals - Cruel Plant. Apparantly some species are able to capture insects and temporarily hold on to them, but I can find little information on this habit.

Cynanchum was relatively unknown in this country until collectors started bringing it back in the mid 1990's from Central China to Korea and Japan. My plant came to my garden just a few weeks ago from a friend ( a blog follower who is moving to Ecuador, who invited me to his garden to 'dig treasures'- nice, right?). You can find plants here at Plant Delights. I am not sure if they still carry it.

The foliage on Rodgersia looks somewhat like large Horse Chestnut foliage.

Lastly, one of my fav plants - Rodgeria. I written enough about this woodland perennial - tall, partial shade, huge, broad leaves - so impressive no matter what species you raise (there are only a handful, each are nice). Look for it at garden centers in the shade plant section.

1 comment :

  1. Anonymous7:49 PM

    dear matt
    i have been "battling" Cynanchum ascryfolium's cousin, C louisiae in one of our gardens. it is interesting looking and handsome, but sinister in behavior--monarch larvae hatched on it do not progress properly. comes in b&b nursery stock and is becoming more and more commonly encountered here.
    all best,
    ~ 02568


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