Baskets of Blooms

It’s hard to say farewell to a species of plant whose end has come, especially one that produced such an abundance of flowers. Alas, my American Basket flowers, Centaurea americana, are done for the year. This is a sad sight:

The stalks of these spent lanky lovelies, tidily tucked in to bins, are on the way to the city of Austin’s composting facility.

I grow these annual native wildflowers, with thanks to Linda of Lagniappe and The Task at Hand, who several years ago graciously mailed to me seeds she’d collected. It’s taken a couple of years, but these regal annuals are now an integral part of my garden family, offering stature and elegance to my summer garden. This year, the basket flower stalks grew especially tall, some reaching to 9 and 10 feet. Most stalks were so tall that I couldn’t enjoy observing many of the blooms that opened atop the stalks. Pollinators filled the air above the garden, zooming from bloom to bloom for pollen and nectar. The lofty flowers certainly earned their keep, even if I was out of the loop. That said, the stalks are multi-branched, so while many flowers were too high for me to observe, there were plenty at human eye level–and their presence was welcome by those wishing only to admire.

A basket bud tops a tall stalk. It waits for maturity, to open, and for multitudes of pollinators to visit.

The common name, Basket flower, comes from the bracts below the flower head which is reminiscent of a woven basket.

As the flower develops, fringed bracts push upwards

…and outwards.

The beginnings of a bloom.

Once the flower fully opens, it’s about 4-5 inches across, a sweet purply-pink, and a pollinator magnet.

A wide variety of pollinators worked these flowers from May through early July. Pollinators like native bees, honeybees, small skippers, larger butterflies, hummingbirds, and flies were at the Basket flowers from sunrise to sunset. A couple of examples of these:

Pipevine Swallowtail, Battus philenor
American Bumblebee, Bombus pensylvanicus

All things die of course, and once the Basket flowers ended their bloom time, seeds developed and the stalks turned from rich green to toasty brown.

During seed development, the pretty pinky blooms morphed to a warm beige; I think the spent flowers are quite attractive. Several of these beauties now reside in a dried flower arrangement in my house.

During winter and early spring, the Basket flower seedlings emerged and grew in the garden, I transplanted some and removed many. As they matured, the stalks grew taller than nearly every other plant in this garden. There was one group of about a dozen that I called ‘the grove’ that I left where they seeded out. I’m not sure why I didn’t take a specific photo of the grove in its prime, but this photo from my last post shows the grove in May at the top right of the garden.

As the flowers of the grove ended their bloom cycle and began to spread their seeds, this is how the group looked.

Small, oval seeds are buried in the fuzzy center of the flower, released with a strong breeze or by working their way out of the center and falling to the ground. There were plenty of House Finches, Lesser Goldfinches, House Sparrows, and Carolina Wrens who enjoyed these seeds. The birds were skittish and I wasn’t particularly patient at getting photos, so I never managed a decent shot of any Basket seed-munching birds, but they will spread the Basket goodness. Besides in my own garden, I expect these seeds will produce plants throughout and beyond the neighborhood.

I’ve collected a few small bags of seeds that I’m donating to our local library for their seed bank.

I suspect if this summer wasn’t so hellishly hot and dry that the pollinators and I would still be enjoying the Basket flowers. Last year, many of my Basket flowers lasted well into fall and were done only after our first freeze of the year. Even though their bloom and seed cycle was shortened this season compared to last, I appreciate what these natives bring to my garden–and look forward to meeting them again next year.

Resting and Robbing

Bees are busy pollinating the summer garden, but like the rest of us, they need rest. Foraging is hard work! This Horsefly-like Carpenter bee, Xylocopa tabaniformis, chose a pretty pink bougainvillea bract as its preferred napping spot.

I watched it for some time as I puttered in the garden and it didn’t move. I’ve seen bees “sleep” on flowers in the past, usually on petals or atop leaves. I’m sure they rest in other places too, but it’s likely that those spots are more private, less noticed by the perspiring gardener. I checked the plant after puttering and the bee had moved on.

This Southern Carpenter bee, Xylocopa micans, participating in nectar robbing, is poised to poke its proboscis into the bloom of a Big Red Sage, Salvia penstemonoides.

Nectar robbing or nectar stealing is a way that various insects, bats, birds, and mammals consume nectar without the benefit to the plant of pollination. In the case of bees, they typically bite or poke a hole in the petal tissue, then sip the nectar, bypassing the parts of the flower where pollination happens. Flowers can be damaged by the robbing, thus preventing further visits from pollinators. As well, some pollinators also recognize when a bloom has been robbed of its nectar, so they move on to other nectar-filled flowers, the robbed flower missing out on pollination. For for various reasons, nectar robbing isn’t generally considered harmful for plants or an ecosystem as a whole, but is simply part of the functional tapestry of a diverse natural space.

Carpenter bees nectar rob because they’re such big bees they can’t fit into certain blooms. Generally, the blooms that bigger bees rob have slender, tubular corollas. This same Southern Carpenter bee is head-and-proboscis-deep into the base of the Big Red sage bloom, sipping the sweet stuff available. There’s no way that big body could nestle in the bloom.

Sometimes, a robber is sprinkled with pollen, perhaps due to buzz pollination. Buzz pollination happens when certain bees vibrate their strong thoracic muscles, vibrating, or sonicating, the pollen grains from flowers’ anthers. During foraging, this Horsefly-like Carpenter bee might have buzzed pollinated on a different flower, its back carrying sprinkles from the loosened pollen onward through the garden. The bee is too big to crawl into this bloom, a Henry Duelberg sage, Salvia farinacea, so stealing is the way to go.

Of course, there are those who pollinate the old-fashioned way, crawling all over a bloom, collecting pollen as they go! This native bee, perhaps a Mining bee, Andrenidae, or a Plasterer bee, Colletidae, enthusiastically worked the flower of a Texas thistle, Cirsium texanum.

Pollinating or robbing, it’s a busy time in the summer garden, especially for those who live in and rely on its bounty. After a hard day in the garden, sleep is bliss.

Gettin’ the Good Stuff

On a cloudy, not-too-windy morning, I strolled through my front garden, stopping to admire one of my Globe Mallow, Sphaeralcea ambigua, shrubs. Its soft silver-green ruffly foliage, paired with the stunning dreamsicle orange blooms melts my gardener’s heart.

Out of the corner of my eye, I glimpsed a streak of movement, though it took a minute or so for me to see it again, catching sight once the flash landed. It was a zippy thing, this flash, not lingering on any surface–until it did. The mystery critter proved to be a Green Sweat Bee, Halictidae, and was all in with the luscious mallow blooms.

I was pleased to see this bee at the mallow, though not surprised: this plant attracts a wide variety of pollinators. I now have enough areas of full sun for this gorgeous native North American plant to grow it in several areas of my garden.

Go get the good stuff, little bee!