The outdoor gardening season is just about done. The monkshood or wolf bane is just coming into flower here in early October, right on schedule. Red October the lastest flowering hosta is just finishing up. And TPP must turn his attention to the glasshouse to find flowers of interest. One bed of succulents has a huge clone of a relatively common Aloe, and every decent sized stem was in flower. There are over 500 species and lots of cultivars, and TPP has no idea what this one is. Any suggestions? Quite colorful in a salmon sort of way. This inflorescence is a near perfect example of a raceme, a single central stem with an ascending helix of stalked flowers. With so many flowers it takes quite a few days to flower from bottom to top. Note how the flowers change position as they come into flower. The lowest flowers are in a pollen accepting phase with the stigma protruding from the corolla. No hummingbirds were around, but a little self-pollination will produce a few fruits. The whole thing makes for quite a visual display.
Let's end the semester in style with a nice Friday fabulous flower. Another one of our tropical epiphytes that provide so much winter color, in this case a gesneriad (Aeschynanthus) of uncertain hybrid ancestry. And for an added bonus you get some of Mrs. Phactor's holiday decor; you generally don't find these in the wild with ribbons, but bet this would help attract more hummingbird pollinators. This plant gets cut back early every summer to grow new shoots while outside, mostly in a partially shady location. It generally flowers quite readily and for quite some time during December and January. The only problem is that the nectar present as a reward to hummingbirds remains unconsumed, so when the corolla drops, so does a big drop of nectar. So don't hang one of these over a carpet or nice piece of furniture. The foliage is actually rather handsome on this variety showing a purple variegated pattern, and although looking delicate, this plant is quite tolerant of dry household conditions.
Bignoniacae, the bignon family, are largely tropical trees and lianas, and most of them have large showy flowers adapted to different pollinators. Catalpa trees and trumpet creeper are our temperate members of this family. Here's one of my captive tropical bignons, Tecomaria capensis, a species widely used as an ornamental in warmer climates. This is just such a classic example of a flower adapted to hummingbird pollination. It's fairly large, it's oriented laterally, it's bright red, has ample nectar, and is scentless. The corolla is highly asymmetrical with the lateral and lower corolla lobes folded back and an over arching upper corolla lobe. The stigma is exerted to contact the bird's head as it arrives, and as the bird moves in closer to get it's beak and tongue down into the corolla tube, then the head contacts the two pair of anthers picking up more pollen. It's a great showy plant and a cheerful mid-winter display.
This particular house/garden plant has always been reluctant to flower. While most of the tropicals flower annually, and reliably, this particular bromeliad (Tillandsia cyanea) often goes a couple of years between flowering events, but then the display is long lasting and quite attractive. Like many tropical plants the long lasting display is produced by colorful bracts composing a large inflorescence. One or two short-lived flowers emerge daily. This is typical of pollination by hermit hummingbirds who travel a path from plant to plant across the rainforest and the inflorescence serves as a beacon for that particular stop on their daily travels. This species has large flowers for this genus. The plant itself is easy enough to grow in a hanging basket of orchid mix and soil. The grassy leaves are tempting to the felines, so growing it aloft keeps them apart.
The extreme seasonality of north central Lincolnland produces three months of tropical weather, three months of arctic weather, and two 3 month periods of very changeable transition. Long ago the Phactor discovered that his tropical plants performed very well if they were quartered outside, hanging from arbors and tree limbs, mostly in light shade, with short sunny periods for the warmer months, usually from late May until September, or like this year, October. Once the nights start getting cold they get unhappy. The shorter days and cooler weather of early fall are quite good at promoting flowering, and people who complain about their house plants not flowering invariably leave them inside year around, and keeping them in well-lit rooms (long nights stimulate flowering). So a month after moving back inside, right on cue, the Thanksgiving cactus (probably Schlumberger truncata, or a similar species, or even a hybrid of this species) began flowering. This particular group of cacti is native to tropical forests of Brazil where they grow as epiphytes. As adaptions to this habitat of frequent rain and rapid drying, tropical or so-called orchid cacti lack the thick spiny stems that most people think are characteristic of cacti and have flattened, leaf-like stems. Certainly the flower is quite spectacular and clearly adapted for hummingbird pollination. You can see how a hummingbird flying in to prob this flower for a nectar reward will upon arrival have its head and neck contact the exerted stigma (red nob)and stamens, both delivering and picking up pollen in that order. Unfortunately this cactus never flowers early enough to interact with our native ruby-throated hummingbirds before one migrates south and the other moves indoors.
This Friday's fabulous flower is Lobelia cardinalis, cardinal flower, although other than its scarlet color, it doesn't resemble a bird at all. The plant is usually about a meter tall, and in the late summer a stand of cardinal flower can make a pretty spectacular display rising above their favorite roadside ditch betraying their preference for wettish places. Like many bright red flowers these are displayed turned slightly upward, without any noticeable scent, and a goodly amount of nectar. Floral biologists anywhere recognize this suite of traits as indicating bird pollination. Distributed widely across eastern North America, the sole pollinator is the ruby-throated hummingbird. It may be that when the cardinal flower finishes flowering at the northern end of its range, that's the signel for hummingbirds to begin their migration southward. Lobelia's in general have flowers with a strong bilateral symmetry, and cardinal flower is no exception, with three corolla lobes out front showing the way to the tube of nectar. Two small corolla lobes curve to the side, sort of staying out of the way. The stamens are fused into a tube at the top through which the style and stigma grow and eventually emerge. Before the stigma opens a ring of bristly hairs encircling the style just below the stigma look a bit like a small bottle brush. When a hummingbird makes contact with the staminal tube and pushes it back just a little, this causes the stationary and bristly style to push pollen up and out of the tube, and action that has been called a "pollen pump", but to me it's a test tube and brush. Try it; you can actuate the mechanism yourself. These flowers are in the pollen dispersing phase. After the flower finishes its pollen dispersal, the stigma opens, the bristles fold back to trap any self pollen remaining, and the flower is ready to accept pollen from the next hummingbird to visit.