I’ll be putting up my Garden Bloggers Bloom Day post up over at Gardening Gone Wild this month, but there’s so much going on outside that I was able to pick out three pretty cool plants for a post here as well. Two of my mid-August picks have great flowers and one has…well, it’s hard to explain why I like it, so I’ll save it for last.
This first one I’m absolutely in love with: white-flowered South African foxglove (Ceratotheca triloba ‘Alba’). I have mixed feelings about white flowers, but I adore this one without reservation: The blooms open a bright, clear white and generally stay that way for a few days before dropping off neatly, so there are no ugly browning blooms to spoil the pristine appearance. I also appreciate the fact that this plant lets me pretend that I can actually succeed with foxgloves (my luck with the classic Digitalis purpurea is irregular, at best).
I started the seeds for this elegant annual indoors in early March and set out the seedlings about 1 foot apart in the third week of May, once it seemed unlikely that we’d get any more frosts. The seedlings took a few weeks to settle in and start growing vigorously, but by mid-July, they were about 3 feet tall and opening their first buds. Now, a month later, they are still flowering freely, and they’re closer to about 5 feet tall. The plants will keep flowering until frost and top out at about 6 feet tall. (If you prefer plants that are lower and bushier, you can pinch out the shoot tips in early to mid-June to promote branching.)
South African foxglove grows well in either full or half-day sun and average garden soil. ‘Alba’ is simply stunning, but the straight species, with its pale purple blooms, is a beauty too. I can’t imagine why it’s so hard to find seeds of South African foxglove: The plants set seed generously, and it’s easy to collect. (If you let some drop, the plants may self-sow as well.) At the moment, I can’t find any commercial sources for ‘Alba’, but you can often get it through the Hardy Plant Society – Mid-Atlantic Group’s seed exchange (one of many excellent reasons to join). Select Seeds may have plants and seeds of the straight species for sale; check here for more information.
My next current favorite is not all that unusual, but I like it anyway: golden lace (Patrinia scabiosifolia). I remember first learning about this perennial back in the early 1990s, through the catalog of the now-closed and much-missed Holbrook Farm and Nursery in North Carolina. I tried to get it going in my old garden but gave up after a few unsuccessful attempts. I tried again here at Hayefield a few years ago and finally got lucky, I think because I started with a fairly small plant and left it in one spot. (I’ve found that the seedlings move fairly easily, but once they have more than 6 leaves or so, they seem to sulk for a while when moved and sometimes just disappear altogether. However, I’ve heard of other gardeners having the opposite experience – poor luck with seedlings and good luck setting out established plants – so you may need to experiment to see what works for you.)
As you can see in this photo, the seedlings vary in height and habit: Some tend to be tall (to 5 or 6 feet) with small flower clusters, while others are more compact (closer to 3 or 4 feet), with broader flower heads. I think they’re all great, and they’re very popular with insects too. The effect is much like that of dill, but the color lasts much longer (here in PA, it’s usually in bloom from mid- or late July well into fall). The reddish to orange fall color of the foliage and stems can be exceptional, too.
Golden lace is fine in average, well-drained garden soil and adapts to either full sun or light shade in Zones 5 to 9. Two on-line sources for the plants are Digging Dog (which lists it with the eccentric common name of “camel’s cover” – don’t ask me!) and Plant Delights. I should give you one warning about golden lace: There are reports that Patrinia is an alternate host for the fungus that causes daylily rust, though what effect that may have on daylilies in American gardens seems to be inconclusive at the moment. I leave it to your own conscience whether you feel irresponsible growing it. For more information, you may want to check out the page on Daylily Rust on the American Hemerocallis Society site.
And now, my third pick: false hemp (Datisca cannabina). I first learned about this one through Piet Oudolf’s Dream Plants for the Natural Garden, and generally, I’ve found that if he likes a plant, it’s worth a try. Plus, I get a pathetic little thrill from growing plants with, you know, *that* word in the botanical name, such as hemp dogbane (Apocynum cannabinum), hemp agrimony (Eupatorium cannabinum), and hemp-leaved hollyhock (Althaea cannabina). For the most part, that bit of name-naughtiness is about the best reason I have for growing this plant, because as far as I can tell, it doesn’t look that much like you-know-what.
False hemp produces upright, 6- to 8-foot-tall, green stems that carry bright green, deeply cut, pinnate leaves and yep, greenish flowers too, so basically, it’s just green. One point of interest is that some plants are male and others are female: the former have somewhat denser bloom clusters, while the females have stringier clusters that develop into chains of small, green seed capsules. The weight of these capsules tends to weigh down the stem tips, so they develop an attractive arching effect.
False hemp grows fine for me in full sun to light shade in average, well-drained soil. It’s listed for Zones 8 to 9 in Oudolf’s book, but it’s been fully hardy here in mid-Zone 6, and I’ve seen references to it being hardy in Zone 5 as well. It’s not a plant you’d depend on for a focal point, but it’s something different for the back of perennial or mixed border. Seeds are available from Plant World Seeds. Plants are available from Plant Delights.