Tag Archives: seeds

Sweetness or Deceit? Attracting Pollinators

28 Sep

Plants are wily, in their own ways. Some beguile with sweetness, others lure with deceit. This weekend at the United States Botanic Garden, I saw examples of both.

The Jamaican Poinsettia (Euphorbia punicea) takes the nicer approach. Below, you can see the brightly colored bracts, which are modified leaves, and a yellow, cup-like flower cluster called a cyathium. Insects are attracted to the clusters by the reddish-pink bracts and are then rewarded with the sugary nectar; in the photo, the glistening drops are almost overflowing from the cups. Arising from the center of the cluster is the pistil (the female reproductive organ), with three curved stigmas at the top, waiting to receive a dusting of pollen from the visiting pollinator.


Successful pollination leads to the development of a seed-bearing fruit. But if the plant has not been successfully pollinated, the fruit may wilt and never produce seeds.

Other plants, such as the Carrion Flower (Stapelia gigantea), attract pollinators by pretending to be (and smell like) something they are not: rotting flesh. You might think that if someone knows a flower smells like a decomposing mammal, s/he would avoid taking a sniff. But no. I partook of the putrid odor more than once, and can confirm that the flower does indeed smell vile. I pointed this out to other passersby, who also conducted repeated olfactory experiments of their own with identical results…. But back to the plant. In addition to its odor, this wrinkly and hairy flower is also meant to look like a decaying, oozing, leathery, peeling dead animal.


And boy, do some insects love that. Perfect spot to lay eggs, with plenty of food for the larvae, or so they think. They are mistaken; their reproductive efforts are futile. But they will have served their purpose: to help ensure the reproduction of the plant by taking and depositing pollen as they go about their business. A devious deception indeed. Here is a close up of the inside of the flower, complete with a green bottle fly circling around, and a pile of ill-fated eggs below.

 

Seed Transport: A Hairy Situation?

22 Oct

When I think of autumn, I think of brilliant, jewel-toned foliage: rich reds, oranges, and yellows. But fall is also a time for brown–and specifically, for really interesting seed pods that have dried up, split open, and offered up their treasures.

In a recent post, I wrote about wind dispersal of seeds via feathery parachutes. Seeds attached to or encased in balls of fluff can travel quite far on a good breeze. But there are other ways for seeds to get around. Catching a ride on a passing animal is one of them. And that is why some seeds are sticky — or hairy, as in the case of Rose of Sharon seeds, which are encircled by a fuzzy ring.

Despite this transport mechanism, however, Rose of Sharon plants are really, really good at self seeding, with dozens of seedlings springing up around the base of the parent plant each year. So while those seeds are designed for adventure, they are really homebodies at heart. And I’ll take a homebody any day, if it puts on a good show (see below).

Rose of Sharon seed pods

Rose of Sharon seeds

Rose of Sharon flower

Iris Seeds

28 Sep

Last weekend, I was ambling down a woody path at Brookside Gardens when I glanced to my left, and then glanced again. What I saw was a small patch of irises, blooms long gone, but with seed pods at the end of the stalks. And one of the pods had split open, revealing bright orange seeds.


Those of you who grow lots of irises may be very familiar with iris seeds, but I had never seen them before. After going home and doing a little research, I now know why: I only have two Japanese irises in my garden; one rarely flowers and the other produces just a couple blooms each year. So it isn’t surprising I haven’t seen any seed pods–my irises aren’t making it easy for bees to pollinate them, and there can’t be any seed pods without successful pollination.

There also can’t be any if each spent iris bloom is carefully removed, which is fairly common practice. Why would a gardener do this? To allow the plant to conserve all its energy for next year rather than spending some of it creating seed pods, which could lead to fewer future blooms on the parent plant. But those seeds could eventually lead to other blooms, and for me, part of the fun in gardening is encountering the occasional nice surprise.

So, assuming a miracle occurs and I do spot an iris seed pod in my garden one year, I would have two options (after letting the pod turn brown and split, harvesting the mature seeds, and drying them out):

  1. plant the seeds in the ground later in the fall (so they can chill throughout winter and so the rain and melting snow can help remove the seeds’ germination inhibitor), or
  2. soak the seeds in daily changes of water for up to two weeks (to get rid of the inhibitor), store them in a plastic bag in the refrigerator (with damp peat moss or potting mix to keep them moist), start them in pots in early spring, and then plant the seedlings. This moist/cold process is known as stratification.

All things considered, I’ll go straight for Option 1. Either way, it may be a year or two before the irises bloom since it takes a while for them to form mature rhizomes. The resulting irises may not look like the parent plant at all, and they may not be quite as fine specimens as other irises–or they might. I like a good mystery.

Feathery Parachutes

8 Sep

There are a variety of ways unexpected plants can crop up in your garden, but often, you can thank the wind for it. If bees play a vital role in pollination, then wind plays a similar role when it comes to seed dispersal. Think of the dandelion, the bane of many gardeners’ existence. It has developed a perfect way of ensuring a next generation by encasing its seeds in balls of fluff. What the wind doesn’t carry away (or lawnmowers cut down and disperse), young children will happily blow into the air–all but guaranteeing a new crop of the ubiquitous yellow flowers right in the middle of your lawn, or your neighbors’.

The Butterfly Weed plant disperses seeds in a similar fashion, but its seeds reside in pods that dry out and then crack open, allowing the feathery parachutes to travel hither and yon (if the Milkweed Bugs that love the seeds and tissue of Butterfly Weed plants don’t get to all the seeds first…). Luckily, there are many, many seeds to go around. And then, it’s up to wind, luck, and Mother Nature. In the bottom two photos, the Butterfly Weed seed parachutes have gotten stuck on 1) a Verbena Bonariensis and 2) a spider web near our brick staircase. I hold out more hope for the former’s prospects than for the latter’s.

 

 

Two Unexpected Appearances

9 Jul

There are few things cheerier than the color orange. In the garden, one of my favorite orange flowers is Butterfly Weed, which as its name suggests, is just as attractive to butterflies as it is to me. Here is a close up from early June:

Now, most of the blooms are gone, and the Butterfly Weed is creating seeds, housed in the pods you can see here:

The pods dry out and crack open, and the seeds disburse in search of new homes.  [Note: People who know about these things (ie, real gardeners) collect the pods and keep the seeds for the following year instead of letting them blow all over the neighborhood. Now that I have finally figured this out, I will attempt to do the same.]

Last year, the seeds I neglected to harvest went their merry ways. One of them floated across the yard and over the fence, where it softly descended into a small patch of mulched earth near our garage. And there, it settled in for the winter, popping up unexpectedly as a new plant this year. I just discovered it a few weeks ago — a very nice surprise indeed. So this evening, I went to take a photo of it, and what did I find? A second unexpected appearance–in this case, a baby rabbit.