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Give Thanks with Pumpkin Fudge

Skip the pie—bring pumpkin fudge and get invited back next year!

Julie McCaffrey —  November 21, 2014 — Leave a comment

No Thanksgiving is complete without a pumpkin dish—and it doesn’t hurt to spice it up with a little something extra…

If you’re ready to start a new tradition (enough already with the pumpkin pie, pumpkin bread, and pumpkin cookies), consider chef Michael Kingsley’s bourbon pumpkin-pecan fudge (available now at the Garden View Café). The bourbon gives the fudge a bit of a kick (and who doesn’t need a little jump-start during the holidays?).

The recipe is simple enough to get the whole family involved. Think butter…pumpkin…toasted pecans—what’s not to like? And what better way to celebrate the season than to spend time together, break fudge together, and give thanks that you’re able to do so?

Pull out your candy thermometer, 4-quart sauce pan, wooden spoon, measuring cups and spoons, 13-by-9-inch pan, aluminum foil, nonstick cooking spray, and seasonal cookie cutters (and get the camera ready—not that anyone is going to lick the spoon…). This is going to be delicious.

Bourbon Pumpkin-Pecan Fudge

PHOTO: Pumpkin fudge

1¾ cups sugar
1¼ cups brown sugar
¾ cup unsalted butter
2/3 cup evaporated milk (5-ounce can)
½ cup canned pumpkin purée (no added sugar) 
2 teaspoons cinnamon
1 teaspoon ginger
¼ teaspoon nutmeg
¼ teaspoon allspice
2¼ cups white chocolate chips
7 ounces marshmallow fluff (any brand)
1 teaspoon salt
1 teaspoon bourbon (optional, but worth it!)
1 teaspoon vanilla extract
1 cup pecans, toasted and chopped

Start by covering a 13-by-9-inch pan with aluminum foil. Spray the covered pan with cooking spray. Sprinkle the chopped pecans evenly over the bottom of the pan. (They do not have to completely cover it.) Set aside.

Combine the sugar, brown sugar, butter, evaporated milk, pumpkin purée, spices, and salt in a pan. Bring to a boil over medium heat and continue to boil until the temperature reaches 236 degrees Fahrenheit on your candy thermometer. Remove from heat.

Working quickly, add the white chocolate chips, marshmallow fluff, bourbon, and vanilla to the pan. Be careful, as this may spatter and will be very hot! Fold ingredients in until completely incorporated. Pour the hot fudge mixture over the chopped pecans and quickly spread evenly; it will immediately start to set up as it cools.

Place the pan uncovered in the refrigerator for at least 3 hours. Your mouth is probably watering already, but unfortunately, it will take this long to set up completely.

After cooling the pan completely for 3 hours, remove the pan from the refrigerator, and turn it upside down on a cutting board. The fudge should pop right out. Peel off the aluminum foil and discard. Want to make your treats extra special? Use cookie cutters to cut your fudge into festive autumn shapes—or maybe dinosaurs if you’re that kind of person—and enjoy!

Note: If you have it in your spice rack, you can substitute 3½ teaspoons of “pumpkin pie spice” for the cinnamon, nutmeg, ginger, and allspice.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Checking the Weather? So Are We

It's how you connect to the Garden every day.

Karen Z. —  November 17, 2014 — 2 Comments

It’s the humblest patch of green at the Chicago Botanic Garden, yet the information gathered there has national implications—and, though you may not realize it, it’s part of your daily prep for work, school, and play.

Although dealing with the weather is part of everyone’s job here, there is no meteorologist on staff at the Garden. Got questions about weather specifics or cooperative weather stations?

In a small, sunny, grassy, flat, fenced-in plot (there’s a reason for that), located on the outer road that encircles the Garden, stands an official National Weather Service Cooperative Station—a collection of instruments that measures the atmospheric conditions of the day. And every morning at 8 a.m., rain (or snow) or shine, a dedicated Garden staff member steps into the plot to read the instruments and record the results, then heads back indoors to transfer the information to the National Weather Service (NWS).

I got to tag along with Celeste VanderMey, Plant Records supervisor, on a recent fall morning for the daily readings.

PHOTO: Celeste at the weather station temperature booth.

Celeste VanderMey explains that its beehive appearance might deter curious critters from poking around inside the weather shelter.

Reading #1: Temperature

Though it looks vaguely like a beehive, the little white structure is a weather shelter that houses two temperature gauges. The maximum temperature thermometer’s mercury rises to the high temperature mark of each day, then stays at the setting until it’s read the next morning. To reset it, Celeste just gives it a spin and the mercury drops.

An alcohol thermometer records the low temperature of each day: pure alcohol molecules move closer together as the temperature drops, shifting a tiny bar that marks the number.

Why no digital thermometers? “Not considered as reliably accurate,” Celeste says.

PHOTO: The weather station rain gauge.

A long metal cylinder like a tiny rocket ship turns out to be a rain gauge. Celeste removes the lid and takes a reading.

Reading #2: Dew

Admittedly the least scientific of the daily measurements, dewfall is indicated as low, moderate, or heavy, simply by examining a surface: the top of the weather shelter or the grass itself.

Reading #3: Rain

The National Weather Service provided us with the rain canister, which can hold up to 10 inches of precipitation (not that we’ve ever had that amount—see records below). Inside is a plastic funnel that directs rainwater into a smaller brass tin. A measuring stick—like a car’s oil dipstick—is inserted, then pulled out and read for rain depth—one-tenth of an inch of rain equals one inch on the stick.

Reading #4: Soil Temperature

A soil thermometer is as handy for home gardeners as it is for us—especially in spring, when it tells gardeners if it’s warm enough to put seeds in the ground. We measure the high and low temperatures of both bare soil and soil under sod/grass (that’s why the plot is flat, sunny, and grassy). An interesting fact: no matter what the air temperature is in winter, the soil seldom drops below 26 degrees (it’s measured at a 4-inch depth). 

PHOTO: Weather station soil temperature gauge.

This gauge takes a reading of bare soil temperatures. Five feet away, another gauge measures the temperature under grass. It’s important information for farmers germinating seed.

Reading #5: Snowfall

It’s low tech, but it works: a white plastic board catches a winter day’s snowfall, which is measured with a yardstick to the tenth of an inch. Two or more inches of snow? Then a core sampling is taken down to the ground, and the core is brought indoors to melt for a water equivalency reading. As mentioned below, the NWS uses this information to predict flooding.

Reading #6: Evaporation

Next we moved to the 4-foot diameter evaporation pan. Its three readings tell forecasters how much water has been absorbed into the atmosphere at this location.

An instrument with an intriguing name, a six’s thermometer, measures both high and low daily temperature of the water in the pan. An anemometer (wind meter) tells how many miles worth of wind has passed this spot. And a hook gauge in a stilling well measures the amount of water lost to evaporation (or added by rain).

PHOTO: An anemometer measures wind speed.

The anemometer attached to the evaporation pan measures the wind speed at an exact height. All weather station gear must meet siting requirements, so that data is measured consistently from station to station.

PHOTO: The hook gauge which usually rests in a container inside the evaporation pan.

The hook gauge rests in a standard-size stilling well inside the evaporation pan—the structure the anemometer is attached to in the previous photo.

Reading #7: River and Lake Levels

Finally, we took a short walk across the road to the south bridge, and the weir (dam) beneath, where the waters of the Garden Lakes meet the Skokie River. Along the banks on each side of the bridge are measurement markers that are read (bring the binoculars!) and recorded daily, although they’re for the Garden’s own record keeping rather than the NWS’s.

Why track the lake and river levels? Flooding is always a threat in our lake system, says Bob Kirschner, director of restoration ecology. “We look at the levels every day,” he explains, “and we can adjust the lake level in anticipation of excessively wet or dry weather forecasts.” All of the Garden’s property is irrigated with water drawn from our lakes. Water levels matter to the half-million lakeshore plants that line the lakes, too—all installed with our normal lake level (623.95 feet above mean sea level) in mind.

PHOTO: Fall in the Great Basin

Fall in the Great Basin

It takes just a few minutes’ time to record the morning’s numbers. Indoors, Celeste logs on to the NWS site and inputs the results, adding noteworthy conditions as needed: fog…haze…ice…thunderstorms.

Staff has been keeping records since 1982. That’s the year that then-Garden president Dr. Roy Mecklenburg, who was keenly interested in meteorology, arranged for the Garden to become a weather station. Stations existed at the time at Midway Airport and in Antioch, with none in between. A few notable numbers since then (again, note that all are since 1982, when our record keeping began):

  • January 2014 holds our record for the snowiest January with 28.7 inches (the 1967 snowfall was higher).
  • February 2014 holds the record for the coldest February: 26.6 degrees was the average high (usually 35.6 degrees).
  • 1993 holds the record for the shortest growing season (number of days between the last frost and first frost) at only 123 days. The average—163 days.
  • August 14, 1987, holds the record for the most rainfall in one day: 5.54 inches.

It’s fascinating to think that the Garden contributes daily to the national weather picture and that there’s always an eye on the weather here (thanks to Celeste, Veronica, Gabriella, Therese, and Lauren). Next time you check on the weather and hear a forecaster say, “and the Chicago Botanic Garden reported ‘x’ inches of rain yesterday,” you’ll know where the information came from: a humble patch of green.

A Bit of Weather Station History

Although it dates back to 1989, the preface of the official National Weather Service Observing Handbook (No. 2) is so wonderfully interesting that it’s blog-worthy on its own. Here’s the text, from page ii, with thanks to the unknown writer:

John Companius Holm’s weather records, taken without the benefit of instruments in 1644 and 1645, were the earliest known observations in the United States. Subsequently such famous personages as George Washington, Thomas Jefferson, and Benjamin Franklin maintained weather records spanning many years.

The first extensive network of cooperative stations was set up in the 1890s as the result of an act of Congress in 1890 that established the Weather Bureau. Today, there are over 11,000 volunteer cooperative observers scattered over the 50 states, taking observations seven days a week throughout the year.

The above observers regularly and conscientiously contribute their time so that their observations can provide the vital information needed to define the climate in their areas. The records are also used constantly to answer questions and guide the actions of public agencies, agricultural and commercial organizations, and individuals. Their records also form a basis for preparedness for national and local emergencies, such as flooding.

PHOTO: apples.

Our most frequently asked question this summer at the Regenstein Fruit & Vegetable Garden: why no apples?

Turns out the weather played a major role.

Last winter’s long, deep cold meant very few flower buds. Then, in spring, when pollinators should have been out to feast on apple flower nectar, the weather was chilly. Since bees don’t fly when it’s under 40 degrees Fahrenheit, little pollination took place. No pollination means no fruit.

Add to that a second factor: apples typically have a two-year boom-bust cycle for fruit bearing. After a bumper crop in 2013, we expected a smaller harvest this year—made even less by the weather conditions above.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Star Appeal for the Holidays

Bling in the season with a striking wreath of your own creation!

Adriana Reyneri —  November 14, 2014 — Leave a comment

You don’t have to be Martha Stewart to fashion this charming star-shaped wreath from branches, raffia, zip ties, and a little duct tape.

PHOTO: Heather models the finished star wreath.

Heather models the finished star wreath.

Find additional inspiration with a selection of wreaths created by Chicago Botanic Garden staff in 2013. See this year’s staff wreaths in our Greenhouse Gallery during Wonderland Express

Just follow these step-by-step instructions from Heather Sherwood, one of our very creative senior horticulturists, to get your own star appeal for the holidays. Heather has selected red-twig dogwood (Cornus sericea) for its warm, cheery color, but the star can be made from any combination of branches and natural materials, including evergreens (such as junipers) and corkscrew willows. If taste dictates, you can bling out with bells, bows, glitter, or other embellishments. Here’s how Heather does it:

Difficulty Level: Intermediate
Time Needed: Two Hours

Materials:  

  • Heavy scissors
  • Pruning shears
  • A large working surface
  • Five heavier red-twig dogwood branches roughly 3/8” in diameter, cut into equal lengths. Heather recommends 30-inch lengths for a front door wreath. You can use shorter lengths to make a smaller star. This will use less plant material and may be quicker and easier to assemble. The base can also be constructed of wooden dowels.
  • Five 4-inch lengths of duct tape  (Heather recommends black.)
  • 20 plastic zip ties (Heather likes 6-inch ties, but shorter ones will do.)
  • Five 1½-inch bundles of red-twig dogwood branches cut in roughly 22-inch lengths (or slightly more than two-thirds of the length of the base branches)
  • Five 1½-inch bundles of twigs cut in roughly 11-inch lengths (or slightly more than one-third of the length of the base twigs)
  • Roughly 90 36-inch lengths of raffia
  • An 8-inch length of floral wire to create a loop for hanging
  • A strand of Christmas lights and additional 8-inch lengths of floral wire (optional)


To Make the Base:

You will need the five heavier branches, duct tape, and zip ties:

  1. Connect the five base branches into one long strand, using the duct tape to create “knuckle” joints: Place the end of the first branch 1 inch away from the top of the duct tape. Position the branch so it covers one-third of the width of the strip. Place the second branch opposite the first branch, leaving a gap between the two branches. Wrap the 1-inch end of the duct tape around the branch ends. Take the longer length of duct tape and wind it around the ends in the other direction. The joint should bend at the gap in the tape between the two branch ends. Create three more joints so that the five base branches form one very long, bendy stick.
  2. Twist into a star: Hold each end of the long, connected stick and bend the first and last joints, creating a rough pentagon shape. Fold the right side of the pentagon over, then the left side. The base twigs should fall into a rough star shape.
  3. Create the final joint in the star: Notch both ends of the last piece of duct tape so it resembles a knuckle bandage. Hold the loose ends of the base sticks together, forming the last point in the star. Center the duct tape under this point. Wrap duct tape ends, one by one, around the point.
  4. Check to see that all five arms of the star are level and even. Rotate star to double check spacing of the points. Adjust as needed.
  5. Use zip ties to secure the base: You’ll see that the base branches intersect to create a pentagram in the center of the star. Loosely wrap a zip tie around each of the intersecting branches at each of the five angles of the pentagram, making sure the ties pull to the back of the star. Check again to make sure the star points are level and even. Tighten the zip locks. If you’re using freshly cut wood, remember that it will shrink and lose diameter.
PHOTO: Place two branch ends together with a gap of 1/2 inch, and tape together with duct tape.

When creating the branch joints, leave a gap between the ends when taping them together, so that the finished joint will bend.

PHOTO: Hold both ends of the long, bendy stick to create a rough pentagon shape.

Hold both ends of the long, bendy stick to create a rough pentagon shape.

PHOTO: Cross the ends over to form the star shape.

Cross the ends over to form the star shape; tape the final joint together.

PHOTO: Secure the inner joints of the base star with zip ties.

Secure the inner joints of the base star with zip ties.


Make the top layer:

You will need the longer and shorter bundles of branches, zip ties, raffia, floral wire, and optional Christmas lights.

  1. Start with the longer bundles of twigs: Lay the first bundle along a base branch, positioning the cut edges just past the inner edge of the inner pentagram. The uncut edges should extend 2 to 3 inches past the point of the star. “I want the stems to ooze around the base,” explains Heather. Secure the bundle with zip ties at two points, the middle of the pentagon, and the middle of the star point. Make sure the zip ties pull to the back of the work. Continue around the base branches, so that the pentagram and one side of each star point are covered with branches.  
  2. Secure the shorter twigs. You’ll arrange the shorter twigs in a similar fashion, laying the cut edges on the outside edge of the pentagram with the natural edges covering the star point. Blend the cut edges, to give the star a woven look, and fan out the natural edges to soften each star point. Secure the shorter branches with one zip tie in the center of the star point.
  3. Double-check the placement of the bundles. Tighten and trim the zip ties.
  4. Cover the zip ties with raffia: Heather has chosen a simple look, tying the raffia in the back with a square knot. You may decide to pull the knots to the front, tie the raffia in a bow, substitute ribbon for the raffia, or add other types of embellishments.
  5. Using four to five strands held together, wrap raffia around once and tie in the back. Continue winding the raffia around and around until it completely covers the zip ties and creates a nice, thick band around the bundle. Tie in the back and trim. Continue until all the zip ties are covered.
  6. Use floral wire to create a loop to hang your star.
PHOTO: Start with longer twigs; uncut edges point outwards towards the star tips.

Start with longer twigs; uncut edges point outward toward the star tips.

PHOTO: Continue placing bundles; one to each side of each star point.

Continue placing bundles; one to each side of each star point.

PHOTO: Next, position and secure shorter bundles of twigs until the base is completely covered.

Next, position and secure shorter bundles of twigs until the base is completely covered.

PHOTO: Cover zip ties with raffia.

Cover the zip ties with raffia or ribbon. Knot in back.

Add lights!

You can backlight your wreath by securing a strand of holiday lights along the back of the base branches. Lay the strand along the star outline and secure it with floral wire threaded between the base sticks and the stick bundles.

PHOTO: Add lights by tying them to the back of the frame with floral wire.

Add lights by tying them to the back of the frame with floral wire.

For more holiday decorating ideas, consider Heather’s classes on Holiday Lighting Techniques or Winter Containers at the Garden.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Wearable Indian Corn

Kathy J. —  November 9, 2014 — Leave a comment

I always look forward to seeing Indian corn in the market and finding it in autumn decorations. Indian corn—in its range of hues from blue to deep maroon to oranges, golds, and yellows—extends the colors of the season long after the tree leaves have faded and been raked away. It is one of November’s icons, reminding us of the cultural and botanical history of the continent.

“You call it corn; we call it maize.”

Or so the 1970s TV ad for Mazola margarine told us.

Long ago, “corn” used to be the term for any grain seed, including barley, wheat, and rye, so naturally the new world plant “maize”—botanically known as Zea mays—was labeled as another kind of corn when it was introduced in Europe. For some reason, the name stuck, and we all think of the sweet yellow stuff on our dinner plates (and its close relatives) as the one and only “corn.”

ILLUSTRATION: A comparison of teosinte vs. modern corn, Zea mays.

This drawing shows the similarities between modern corn and its ancestor, teosinte, after 10,000 years of cultivation. Illustration by Nicolle Rager Fuller, National Science Foundation

There are actually many varieties of maize-corn. Archaeologists are pretty sure that all of them resulted from the domestication and selective cultivation of the grass teosinte (pronounced tay-oh-SIN-tee), around 10,000 years ago by the people living in what is now Mexico. Over time, maize became a staple crop, yielding different varieties of nutritious and versatile grains throughout the American continent.

PHOTO: Three ears of Indian corn leaning against a pumpkin.

The farmers in my neighborhood sell Indian corn in bundles of three alongside gourds, pumpkins, and bundles of straw.

Indian corn is related to popcorn. These kinds of maize differ from other kinds in that they have a harder outer coating and a starchy interior with a bit of water inside the seed, or kernel. Popcorn pops when the kernel is heated quickly at a high temperature, causing the water inside the seed to suddenly turn into steam, inflating the starch. The sweet corn we love to eat and the dent corn used for tortilla chips and livestock feed will not produce a fluffy white snack when heated.

We can exploit these properties of Indian corn and turn the kernels into necklace beads to wear during the season. 

How to make an Indian corn necklace

You will need the following:

  • Indian corn (one average-size cob will make two necklaces)
  • a sharp embroidery needle, long, with a large eye
  • string; you can use ordinary sewing thread, but a little heavier is better
  • a pot of water to cook and soften the corn
PHOTO: Indian corn.

My daughter chose this bundle of Indian corn because she liked both the deep red of cob on the left and the pinkish seeds of the one in the middle—but not for the same necklace.

First, remove all the kernels from the cob. You can wedge a butter knife between the rows of kernels and twist to pop out the seeds. Once you get some of the cob stripped, you can rub the kernels loose with your thumb.

PHOTO: a bowl full of colored corn seeds, or kernels.

These seeds have been removed from the cob and are ready for boiling to soften them.

Place the corn kernels in a pot of water and boil for 30 minutes. (This isn’t hot enough for the corn to pop.) Test for doneness by removing three  kernels. If you can push a needle through each of them easily, they are ready. Remove the pot from the heat and allow to cool. You can add cold water to cool them faster, but be sure to leave them soaking so they do not dry out, even when you are stringing them. (Pushing the needle through dry kernels can be a painful experience.)

While the corn is cooling, cut a string about three times as long as you would like your necklace to be. (You can work in shorter sections and tie them together, but it won’t look as nice.) Thread the needle and double the string; then knot the ends.

Now, select kernels in the colors you like, or pick them up randomly so the string resembles the color pattern of the corn cob. Try to pick softer pieces. Hold each kernel by the sides, and push the needle through the middle of the kernel so that the needle is not pointing toward your finger. Then slide it down the string. Leave a few inches of string below the first piece so you have some string to tie when you’re finished.  

PHOTO: This image shows how holding the seed by the sides puts fingers out of the way of the sharp end of the needle.

It is very important to hold the kernel by its sides as you poke the needle through the middle of the seed.

If the kernel is too hard and resists piercing, do not force it! Try to push the needle through at another angle, or discard that piece and select a softer one. This is important because you will prick yourself with the sharp needle if you are not careful. In fact, you’ll probably stab yourself at least once even if you are careful, so this is not a project for very young children. 

Pack the moist seeds close together on the string. As they dry, they will shrink in size. You may want to slide them together a little tighter so the string doesn’t show, but you’ll also want to leave enough wiggle room so the necklace has flexibility. When your string of corn is long enough, allow the seeds to dry completely. Then tie the ends together and you will have an attractive necklace to wear to Thanksgiving dinner or other festive gatherings!

PHOTO: Indian corn necklaces.

The finished necklaces look great layered in different lengths and colors.

One final note: when I made a corn necklace in third grade as part of a unit on Native American culture, I was under the impression that indigenous people of long ago made and wore necklaces like this. No way. All corn was grown for food, and it  was needed to sustain the population, so it would not have been turned into jewelry. This season, we can be thankful for the plentiful food we have to eat, and we can appreciate the beautiful colors of the corn as decoration during the feast.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Parents! Here’s a kid-friendly, fun-to-make idea from Kasey Bersett Eaves, who “talked squash” with fall-minded visitors at the Regenstein Fruit & Vegetable Garden on a gorgeous fall weekend.

With winter squash and pumpkins readily available at grocery stores and farmers’ markets, a nicely spiced fruit leather is a great way to use a post-Halloween pumpkin (uncarved) or extra can of purée—and to get kids to eat their vegetables in a new and tasty way. Super simple to assemble, it’s a whole lot healthier than candy!

Kids AND adults love the cinnamon-y pumpkin flavor.

Kids and adults love the cinnamon-y pumpkin flavor.

Pumpkin-spiced Snack Leather

  • 1 can of plain pumpkin or 3½ cups of cooked pumpkin pulp*
  • 1 cup of unsweetened applesauce
  • Cinnamon, nutmeg, cloves, and honey according to taste

Purée all ingredients together by hand or in a blender or food processor.

Spread purée on a foil-lined or greased cookie sheet, and smooth until just a little more than ¼-inch thick. Bake on your oven’s lowest setting (around 150 degrees) until no longer sticky to the touch (this takes close to eight hours).

Remove and cool until you can lift the edges and corners of the pumpkin leather off the foil or cookie sheet. Peel off and cut into strips. Roll each strip into plastic wrap and refrigerate until ready to eat.

If you have a food dehydrator, it’s even simpler. Spread the purée on the plastic sheeting provided with your dehydrator—or wax paper—and dehydrate until no longer sticky. Roll, refrigerate, and snack away!

It's a kid-friendly process: first, blend puree with applesauce and spices to taste.

It’s a kid-friendly process: first, blend purée with applesauce and spices to taste.

A tin foil base rolls up easily.

A tin foil lining makes cleanup easy.

*Basic Technique for Cooked Squash

Fresh-cut pumpkin (which is actually a squash) has a much higher water content than canned pumpkin. You will need to cook your pumpkin first, and use more fresh pulp. Cut your squash in half and remove the seeds. Place the squash skinside down on a baking dish, and bake at 350 degrees until the flesh is tender and the cut edges have caramelized. Remove the squash from the oven and let it rest until cool. Scoop out the pulp and discard the cooked skins.

See Kasey’s summer post, too — “Herbal Mixology


©2014 Chicago Botanic Garden and my.chicagobotanic.org