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Growing a Bean in a Bag

Or, How to Train Your Plant Part 2 1/2

Kathy J. —  May 26, 2013 — Leave a comment

Garden blog followers may remember that in “How to Train Your Plant” I demonstrated a way to grow a bean seed in a plastic bag to test geotropism. I started working on that project around Thanksgiving week last year. At that time, I started a few bean bags just to see what would happen. I kept one seed growing in the bag all winter, adding water as needed.

PHOTO: A ziptop bag was used as a container to grow a bean plant. Roots, stem, leaves, and the remains of the original seed are visible.

The bean plant grew for five months, leaning toward the window in my office.

The plant produced a white flower about a month ago. I should have taken a picture. Now this week I discovered a seedpod growing where the flower had been! In the picture, you can see the wilted flower petals still hanging from the tip of the reddish colored pod. Botanically speaking, this is the fruit of the plant, even though you might not think of beans as fruit in your diet.

PHOTO: a red bean pod, about 2 and a half inches long is attached to the stem of the plant.

The red fruit was hidden under the leaves.

So if you try this activity, and you stick with it for six months, you, too, may be rewarded with a little treasure!


©2013 Chicago Botanic Garden and my.chicagobotanic.org

This year, it sure felt like spring was a long time coming — especially compared to last year when it seemed that we went straight into summer! I wonder how the wildflower timing of spring compared to previous years in the Chicago area…

Mayapples, April 25, 2012

Mayapples, April 25, 2012

Mayapples, May 2, 2013

Mayapples, May 2, 2013

For several years now, I’ve been working on a web-based citizen scientist project, called Project BudBurst, with colleagues at the National Ecological Observatory Network (NEON). We study the phenology — the timing of natural events like blooming, fruiting, and leaf fall — of plants around the country. Our participants track when plants bloom in their area, and we compare the reports to records from other parts of the country.

You can help us collect data! Sign up to help at Project BudBurst.

For instance, I’ve been tracking when the first forsythia flower opens on the plants near the Garden’s front gate since 2007. The earliest bloom I have on record in that time was last year, on March 15, 2012. The latest first flower for this specimen was this year, on April 20, 2013. In 2007 and 2008, however, we also had first flowers in mid-April (April 16, 2007, and April 17, 2008, respectively). So, as we look back in time, this year’s bloom time doesn’t feel quite so late. In the graph below we show the variation in flowering dates (using Julian dates, which standardize for differences in dates between nonleap and leap years).

forsythia data

In the Chicago area, we have a wealth of phenology data collected by the authors of our local flora, Plants of the Chicago Region by Swink and Wilhelm (1994). While they were gathering data for their book, they recorded when they saw plants in bloom from the late 1950s to the early 1990s. They record the forsythia bloom period as April 25 to May 5. So, when we look still further back in time, our “late” spring is much earlier than it has been in the past.

I took a similar look at several other species, both native and nonnative, for which we have both Project BudBurst data and data from Swink and Wilhelm’s book. About 70 percent of the species have earlier flowering dates in the last six years compared to those recorded by Swink and Wilhelm. Some of the species that have advanced their flowering dates are in the table below.

Species Earliest First Flower Observations
Common name
Genus species
Swink & Wilhelm
1950s – 1990s
Project BudBurst
2007 – 2012
Days
Advanced
Forsythia
Forsythia x intermedia
April 25 March 15 -40
Spiderwort
Tradescantia ohiensis
May 14 April 12 -32
Dogtooth violet
Erythronium americanum
April 6 March 20 -17
Red Maple
Acer rubrum
March 20 March 6 -14
Mayapple
Podophyllum peltatum
May 1 April 17 -13
Lilac
Syringa vulgaris
May 3 March 20 -44
Black locust
Robinia pseudoacacia
May 9 April 20 -19
Bradford pear
Pyrus calleryana
April 15 April 13 -2

Plant phenology, particularly when plants leaf out and bloom in the spring, is remarkably sensitive to the annual weather. Looking at phenological records over much longer periods of time can tell us a lot about how the climate is changing. Many scientists are comparing contemporary bloom times with historic bloom times recorded by naturalists like Aldo Leopold in the early 1900s, and Henry David Thoreau in the mid 1800s, as well as records kept by farmers, gardeners, and others interested in the natural world. Two of the longest phenological data sets are those maintained for cherry blossoms in Japan (dating back to 900 AD) and for grape harvest dates by winemakers in Switzerland (dating back to 1480 AD).

Plants have so much to tell us, if we take the time to listen!


©2013 Chicago Botanic Garden and my.chicagobotanic.org

How to Train Your Plant II

Part 2: Using Light

Kathy J. —  March 8, 2013 — Leave a comment

Blog followers will remember that in the first “How to Train Your Plant” post, we demonstrated how plants respond to the gravitational pull of the earth. Geotropism is difficult to overcome, but that didn’t stop me from trying to make a plant grow sideways through a maze. You can try this activity at home.

You will need these items:

  • a shoebox (or any kind of box)
  • cardboard to make dividers
  • duct tape (or any opaque tape)
  • soaked bean seeds—I used different beans from a soup mix
  • a container with soil
PHOTO: The materials for the maze are displayed.

You’ll need a shoe box, cardboard dividers, seeds, a pot with soil medium, and of course scissors and tape for constructing the maze.

Stand the box on its side. Then cut two pieces of cardboard to fit in the box and make divisions. You’ll want these to fit as snugly as possible inside the box, but they don’t have to be perfect. The tape will fix that. Cut a large window in each divider. Cut a window on one end of the box. Tape the dividers in place as shown in the picture.

PHOTO: The maze assembly is shown in the shoebox. There are two dividers with cut out windows and a whole in the side of the box for light to shine sideways on the sprouting bean seeds.

Pardon the crude appearance of this maze. I wasn’t going for style points.

Plant the seeds in the soil and put the container on the side opposite of the hole you cut. Just for fun, I used several different seeds from a bean soup mix to see if one kind would get through the maze better than the others. It was like a bean-seed “race.” You can try whatever you like.

Make sure the holes in the divisions are big enough to allow lots of light in from the side, and don’t vary the height too much. Remember, we are fighting the plant’s tendency to grow up—if it’s too challenging, it won’t work. Trust me, I learned this the hard way.

When the maze is complete, give your beans a last bit of water, and maybe a kiss, and then close the box. Apply tape along the top edge, to secure it and reduce light. Then put it next to a window and wait.

And wait.

It’s going to take a few weeks. Remember, horticulturists are very patient. Open the box every few days or so to be sure it has not dried out. Add a little water, but only enough to moisten the soil if it is very dry.

When you see the bean plant emerging through the open window in the box, open it and take a look. How long this will take will depend on the kind of beans you use, how far the plant has to grow, and how warm the room is.  

The beans have sprouted and are moving toward the light

The beans have sprouted and are moving toward the light

 It took my beans about five weeks to grow through the second window.

 

PHOTO: all of the bean sprouts are leaning toward the light.

The beans were definitely torn between growing up and growing in the direction of the light.

 

The winning sprouts, which I believe were lentils, did not actually make it through to the last window when I took this picture, and I’m not sure it has enough “umph” to do it. Still, notice how all of the plants leaned toward the light and most of them grew through the first window. That is a positive result!

What is going on here?

This activity demonstrates phototropism. Photo is the Latin word for “light,” and you will remember that a tropism refers to an organism’s response to stimulus, so that phototropism means plants grow toward the light.

It makes sense for plants to reach for the light because they need light to make sugars, their source of energy. Normally, growing up against the pull of gravity is also growing toward the light. In this activity, we changed that condition, forcing the beans to deviate from their normal course to get the light they needed.

The sprouts that grew the farthest and were closest to completing the maze had leggy stems that would not support growth upward to the last window. If I leave them a few more weeks, they could possibly grow along the bottom and then up the side of the box. I’ll have to wait and see.


©2013 Chicago Botanic Garden and my.chicagobotanic.org

Project Overview:
Shannon Still and Nick Jensen work on a project studying the impact of climate change on the distribution of rare plants in the western United States. The grant, funded through the Bureau of Land Management (BLM), examines the changes in projected species distributions between now and 2080. The goal of the research is to help BLM to make informed management decisions regarding rare plants. The research takes them to many exciting destinations as they search for rare plants in the west.

 

habit of Enceliopsis argophylla

Habitat of Enceliopsis argophylla, which thrives in gypsum-rich soil.

The silverleaf sunray (Enceliopsis argophylla),  is a photogenic species in the Asteraceae, or sunflower, family. This rare plant grows in basal clumps of silver-colored, hairy leaves with flowers extended on long stalks, and the entire plant may reach 2 feet tall. The flowers nod with maturity.

The large yellow daisy flowers are 3 to 4 inches across when open. They are quite a sight and stand in stark contrast to the habitat. Due to the extreme habitat, silverleaf sunray offers one of the more striking photo opportunities as the plants grow from a barren landscape.

Silverleaf sunray on a barren hillside.

Silverleaf sunray on a barren hillside


Nick Jensen with a silverleaf sunray.

Nick Jensen with a silverleaf sunray

These gems are found in Clark County, Nevada, east of Las Vegas in the Lake Mead area. They are also found in Mohave County, Arizona, close to Lake Mead.

The habitat for the silverleaf sunray has been encroached by Lake Mead and is threatened by off-highway vehicle use to a minor extent. The habitat in which the sunray grows is easily damaged due to the fragile soil environment (see photos to left) in which the species lives. Much like the dwarf bear-poppy (Arctomecon humilis), the silverleaf sunray grows in a gypsum-rich soil that typically has a healthy soil crust. Damage to this crust can allow invasive plants to grow more easily.

The Bureau of Land Management lists the silverleaf sunray as a sensitive species in Nevada and the species was considered, but rejected, for protection under the Endangered Species Act. Around Lake Mead the silverleaf sunray grows with the golden bear-claw poppy or Las Vegas bear-poppy (Arctomecon californica), a federally listed species. So while the species is not federally listed, the habitat is often protected due to the proximity of other federally listed rare plants.

Side view of the silverleaf sunray flower.

Silverleaf sunray is a striking plant that grows in close proximity to urban and recreation areas. If you are ever in the Las Vegas area, it is worth traveling the short distance to see these plants.


©2013 Chicago Botanic Garden and my.chicagobotanic.org

How to Train Your Plant

Part 1: Using Gravity

Kathy J. —  February 5, 2013 — 1 Comment

Since it’s winter, and we’re all stuck looking at leafless plants outside, why not try growing some plants indoors? Better still, why not experiment with your plants to understand them better?

In this activity, you will confuse a bean sprout and train it to grow in any direction you want. Sound like fun?

You will need:

  • a gallon-size zip-top bag
  • paper towels, preferably 2-ply (if they are single-ply, double them)
  • a pinto, lima, or kidney bean (try whatever you have) soaked in water overnight
  • a stapler
  • water
  • tape

Lay the paper towel flat inside the plastic bag. If it doesn’t fit exactly, fold the edge of the paper towel.

Put a staple in the middle of the bag, and place the bean just over the staple. Add two staples that are separated by more than the length of the bean. 

IM000700

The staples hold the bean in place, but should give enough room for the bean to grow between the staples. Watch to see how the bean grows and needs the space. Add just enough water to the bag to wet the paper towel. Take care not to have a pool of excess water in the bag.

Now tape the bag to a wall, or your refrigerator, or a window if it’s not cold. That’s right, put it right on a vertical surface. Don’t close the bag, because it’s good to allow water and air to move in and out. The picture shows you what it should look like. (Ignore the four staples, only put three on yours. I discovered that four staples trap the seed and ruin the activity.)

IM000624

As soon as your plant has grown a root and a stem that is 1-2 inches long, turn the bag one quarter turn and put it back. You may have to wait a week – less if your bean is warm, more if your bean is in a cooler location, like my office.

This is what it may look like at this stage after I turned it.

IM000679

Now wait. When the sprout has grown another inch or so, turn the bag again in the same direction. Since the opening of your bag will now be on the bottom, you should seal it. Then wait.

Yes, I know, you have to wait a while to get results. The timing will depend on the level of light and the temperature. That’s the way it goes with growing plants. Horticulturists – the people who grow plants – are some of the most patient people you will ever meet!

Here are the results of one bag I started in early January, about three weeks ago. Since I turned the bag clockwise, the roots and stem appear to be going around counter-clockwise.

IM000701

From here on it’s up to you.  Let the plant grow and turn the bag when you want to change the direction of growth, let it go for as long as you like.  Can you make it grow in a full circle around the middle of the bag? 

What is Going On Here?

Plants are affected by the gravitational pull of the earth. When you turn the bag, you change the direction of the force and the plant responds by changing direction of growth. This phenomenon is called geotropism. A tropism describes an organism’s response to a stimulus. In this case, the “geo” refers to the Earth, and it is the scientific way of saying that the earth makes leaves grow up and roots grow down. This phenomenon may also be called gravitropism.

The Garden’s horticulturists play with gravitropism. Look at this picture of the Visitor Center bridge in fall. Notice the gorgeous pink mums hanging from the trellis.

i-ZST28XH-L

Left alone, the stems of these plants would naturally grow up like the mums planted on the sides of the bridge. Our horticulturists train the stems to grow down, cascading over the sides of their container, by tying small weights on the stems while the plants are growing in the greenhouses. They actually use metal nuts from a hardware store! The weights are removed before the planters go on display, and they look fabulous, thanks to the horticulturists’ success in playing with the plant’s response to gravity.


©2013 Chicago Botanic Garden and my.chicagobotanic.org