The Power of Plants: Botanical Weightlifters

There are things I look forward to seeing every season.

In spring, I watch for “mighty plants” that emerge from the ground with enough force to heave the soil above ground. These botanical weightlifters—the bulbs, grasses, and other emergent plants—pushing up soil that was compressed by a blanket of snow never fail to impress me. I am in awe of the strength of plants. 

PHOTO: Daffodil leaves have pushed through the mulch, lifting it off the ground.
Daffodil leaves erupted from the ground in March and lifted the mulch in the beds around the Regenstein Learning Campus.

Seeing bulbs coming up all around me inspires lots of questions. I want to understand how this is possible and I want to test their strength. So I spent a few weeks playing around with this phenomenon in the Learning Center’s Boeing Nature Laboratory. 

To begin, I wanted to demonstrate that seeds will lift soil in a pot. I soaked bunch of wheat seeds overnight and planted them in a pot. I covered them with a generous amount of potting soil (about a 1/2-inch layer) and I tamped the soil down gently so that it would be compressed—like the topsoil might be after a winter of snow cover. Three days later, I had results! I sprayed the soil disk to give it a little adhesion, so I could see how long it would hold together as the grass lifted it up.

PHOTO: A few days after planting the soaked wheat seeds, they are already sprouting and pushing up the soil.
Day 3 after planting the seeds: They are pushing up the compressed layer of soil.
PHOTO: The wheat leaves have grown to an inch over the pot and are holding up a disk of soil.
Day 4: The leaves have pushed the soil up a little more.
PHOTO: The wheat is 2-3 inches above the pot and still suspending the disk of soil.
Day 5: The soil is light and there are a lot of wheat plants, so they continue to lift the soil.
PHOTO: The grass is now 4-5 inches tall and the disk of soil is on top, but leaning to the side, about to fall off.
Day 6: “Get off me, Soil! – Umph!”
PHOTO: The disk of soil that was lifted by the grass has fallen to the side of the pot.
Day 7: Phew!

That was so much fun, I tried the same thing with a bunch of bean seeds.

PHOTO: the top of the soil is rising about a half inch out of the pot.
Bean sprouts pushing…
PHOTO: the sprouting beans can be seen pushing up the top of the soil, now 1-2 inches over the top of the pot.
…pushing…
PHOTO: a dozen bean plants are growing out of the pot and pushing the top soil disk to the side.
…and bursting from inside the pot.

This demonstration was pretty easy and impressive. It is a simple activity to illustrate how plants and other living things change their environment to suit their needs (which is a disciplinary core idea in Next Generation Science Standards for kindergarten). I recommend doing it in the classroom or at home, just for fun.

This is just the beginning. I will be sharing the results in a future blog post. But before I do, I would like to make a few points about the nature of science and how scientists work. 

  1. Science is a collection of established facts and ideas about the world, gathered over hundreds of years. It is also the process by which these facts are learned. Science is both “knowing” and “doing.”
  2. Discoveries start when you watch nature and ask questions, as I did in watching spring bulbs come up. Before beginning an experiment, scientists play. They mess around with materials and concoct crazy ideas. They are constantly asking, “I wonder what will happen if I do ___ ?” That is when discoveries actually happen.
  3. Scientists do formal experiments with purpose, hypothesis, procedures, results, and conclusions after they think they have made a discovery. They use the experiment to test their discovery and provide convincing evidence to support it. In some cases, the experiment disproves a fact or idea, which is a different kind of new understanding about the world. 

I have to agree with Boyce Tankersley, the Garden’s director of Living Plant Documentation, who recently wrote “The SciFi Rant.” Those of us who lean toward botany instead of horticulture are more interested in growing plants to yield ideas rather than meals. In my continuing investigation, I have two goals, and neither is to produce anything to eat.

First, I want to determine the strength of sprouting seeds and see how far I can push them. For example, how many bean sprouts will it take to lift a coconut? I want to find a standard way to measure seed strength.

Second, I want to establish a reliable method for experimenting with seed strength so teachers and students can replicate the procedure, modify it as needed, and use it for their own investigations without going through the awkward phase of figuring out the best way to do this.

PHOTO: a 6 inch square pot is topped with a round plastic lid and a coconut.
Will the mighty beans sprouting under this menacing coconut have the power to lift it off the top edge of a pot? Stay tuned…

I invite you on my journey.
(To be continued.)


©2018 Chicago Botanic Garden and my.chicagobotanic.org

Gardening in Winter: Dos and Don’ts

Welcome to winter, one of the best seasons for gardeners. You have time to plan, prune, and enjoy those houseplants that don’t get much love during the outdoor growing season. Make the most of your winter gardening with these dos and don’ts from Chicago Botanic Garden experts.

DO prune your deciduous trees. From mid-November to mid-March, it’s much easier to prune because you’ll be able to better see a tree’s branching structure and there is less chance of transmitting diseases from one plant to another.

Winter is the perfect time to prune deciduous trees or remove nuisance buckthorn.
Winter is the perfect time to prune deciduous trees or remove nuisance buckthorn.

DON’T prune conifers. Needled evergreens can be pruned in late winter or early spring, before growth begins. Arborvitae should be pruned during spring and early summer.

DO water newly planted trees and shrubs that might be in the path of salt spray from salted roads during periods of winter thaw. Consider wrapping vulnerable trees to prevent damage from salt and extreme temperatures.

DON’T overwater houseplants. Because of shorter days and reduced humidity, most houseplants aren’t in an active growth phase, so they’ll require less water and fertilizer.

DO keep houseplants away from cold drafts, radiators, hot air vents, and cold windows. Plants growing in sunny east- or north-facing windows may benefit from being moved to a southern or western exposure for winter.

DON’T try to remove ice or snow that has frozen onto your outdoor plants. You might inadvertently damage them. Let it melt off on its own.

DO start to plan your garden for the new year. Order seeds and bulbs during the winter so you’ll be ready to plant in the spring. Need some help? Come to Super Seed Weekend on January 27 and 28 to talk to experts, attend a workshop, and find seeds and bulbs for your garden.

Ornithogalum 'Chesapeake Snowflake'
Ornithogalum ‘Chesapeake Snowflake’

Get more indoor and outdoor plant care tips with our monthly plant care checklists.

Plan for spring with a class in Front Yard Design, Backyard DesignGrowing Salads Indoors, or Small Space Food Gardens


©2018 Chicago Botanic Garden and my.chicagobotanic.org

Three easy, harvest-inspired Thanksgiving centerpieces

Full bellies and full hearts. It’s what great Thanksgivings are made of. This year, add a special touch to your holiday table with harvest-inspired centerpieces that bring the whole family together.

We asked Nancy Clifton, program specialist at the Chicago Botanic Garden, to share some easy, crafty ideas that would fit a variety of party styles. Here are three centerpieces you can create (and mix-and-match) to impress your guests.

A Festive Friendsgiving

Friends are family you choose, as the saying goes. For these cozy gatherings, pick your own flowers, too. Here’s how you can make Thanksgiving-themed floral centerpieces like a pro:

Thanksgiving Flower Arrangements

Thanksgiving Flower Arrangements

Pick flowers in autumn colors. Buy a few bunches of flowers in different fall colors and textures at your local grocery store. Nancy chose red roses, yellow mums, red-yellow mums, and hypericum berries to give the arrangements some variety.

Paint Thanksgiving mason jars. If you want to up your Thanksgiving game, paint your vases in holiday colors such as brown, orange, and ivory. Nancy used craft paint on mason jars, and sanded the lettering on the jars to give them a vintage look.

Save time by measuring flowers. Nancy’s time-saving hack is to trim one flower with pruners and remove foliage at the bottom of the stem. Place that flower in the mason jar vase. If you’re happy with the height, remove the flower and use it as a measuring tool to trim the rest of your flowers. Make sure you trim the flowers low enough so you can see your friends’ faces!

Impress-the-in-laws Pumpkin Planters

If you’ve got some serious entertaining to do (or at least want more excuses to use your hot-glue gun), wow your crowd with pumpkin succulent centerpieces. The best part? You can repurpose and eat parts of them when you’re done.

See the demo video on YouTube here.

Thanksgiving Centerpiece
The finished succulent and squash centerpiece

Gather the basic tools and ingredients. Grab a hot-glue gun, reindeer moss, and floral picks from the craft store. At your local grocery store, find small- and medium-sized pumpkins (you will want several), a succulent container, bunches of kale, and cabbages.

Assemble the planters. Cut the ends off of your succulents so they have a flat base, and set them aside. Adhere moss to the top of your medium-sized pumpkins with your hot-glue gun. Once the glue is dried, add the succulents on top of the moss, and adhere with hot glue or floral picks.

Arrange your centerpiece. When the pumpkins are dried, place them in the center of a large decorative tray. Add smaller pumpkins, bunches of kale, and cabbages to tray, arranging them in a bountiful display. You can even paint the stems of your small pumpkins with glitter-paint to give them extra-fancy glitz.

Give Thanks Table Runner

One of our favorite Thanksgiving traditions is sharing what we’re grateful for. A fun way to involve the whole family in this tradition is to have everyone write their “thanks”on a centerpiece mural.

Buy a roll of Kraft paper. Think of this as your table runner. You may want to lay this on top of a tablecloth to protect your table from stray doodles.

Decorate with thanks. Place markers around the table for guests to write their thanks on the runner.

Add an intimate glow. Nancy added pumpkin planters, candles, and string lights to the centerpiece to bring a warm, enchanting feeling to your party.

We hope you enjoy creating these centerpieces, and have a happy Thanksgiving!

Find more of Nancy’s ideas, check out her 101 on creating Thanksgiving cornucopias.


©2017 Chicago Botanic Garden and my.chicagobotanic.org

Moving Houseplants Back Indoors

In spite of the recent 90 degree temperatures, it’s time to start thinking about moving your houseplants inside.

The best time to do this is when temperatures outside are relatively close to the temperatures indoors, meaning mid- to late September. Before you move everything in, however, there are four quick steps you’ll want to take to help ensure a successful winter of windowsill gardening.

The same care tips also apply to overwintering tropical plants such as palms and bromeliads
The same care tips also apply to overwintering tropical plants, such as palms and bromeliads.

1. Clean up any dead or damaged growth.

Why bring any additional mess indoors when you don’t have to? Carefully remove any broken branches, sunburned leaves, or otherwise unsightly growth from your plants.

2. Lightly trim back plants as needed.

This step is a bit optional, and you really only need to do it if your plants have become large and overgrown. Never remove more than one-third of the growth at a time. Removing more can stress the plant and send it into shock, which can be hard to recover from indoors.

3. Check thoroughly for pests, and treat as needed.

One of the biggest ways to set yourself up for success is to start with clean plants. There are several pests that can cause problems indoors. The most common are mealybugs, spider mites, scale, and aphids. Insecticidal soap is a lower toxicity insecticide that is safe for most houseplants and will take care of nearly any pest problem you might have. As with any chemical, make sure to follow all package instructions. It is NOT recommended to use soapy water—this eats away at the cuticle (a protective waxy layer on the leaf), making it more vulnerable to disease problems in the future. For specific pest recommendations, contact our Plant Information Service.

Large-leaved plants are particularly susceptible to spider mites.
Large-leaved plants are particularly susceptible to spider mites.
Spider mites can also cause brown edges that mimic sunburn. Look for the telltale webbing to determine if you have mites.
Spider mites can also cause brown edges that mimic sunburn. Look for the telltale webbing to determine if you have mites.
Mealybug feeding on the stem of Dioscorea elephantipes
Mealybug feeding on the stem of Dioscorea elephantipes
Sunburn causes brown spots on leaves.
Sunburn causes brown spots on leaves. Trimming off damaged leaves helps keep plants looking good all winter.

4. Finally, resist the urge to repot unless necessary.

Sometimes plants have simply grown too large for their pots, in which case it’s OK to repot. But don’t repot if the plant doesn’t need it, as this will add unnecessary stress that could harm the plant in the long term. Always use soil specifically for containers (potting soil). Black dirt is too heavy and will encourage rot. When repotting, select a new pot that’s only 1 or 2 inches larger in diameter. Anything much larger than that will encourage rot because the soil will stay wet for a long time.


©2017 Chicago Botanic Garden and my.chicagobotanic.org

Getting That Tropical Look

This season’s Brazil in the Garden exhibition features a bold tropical look at the Chicago Botanic Garden—you can get that same vibrant feel in your home garden, using perennial plants.

Surprisingly, there are a number of plants that thrive in the Chicago area in spite of their tropical looks. With attributes ranging from huge leaves, delicious fruits, or potent fragrances, these trees and shrubs will add a tropical splash to your backyard year after year.

Magnolia ashei is one of the most tropical-looking plants at the Chicago Botanic Garden. It features huge leaves, huge flowers, and huge fruits. The leaves can grow up to 36 inches long, the flowers can be more than a foot across, and the fruits are up to 5 inches long and turn bright red. Magnolia ashei has an irregular growth habit and makes a bold specimen. Look for this one in the Native Plant Garden (however, this plant is not an Illinois native).

PHOTO: Magnolia ashei
Magnolia ashei has beautiful leaves and intriguing fruit.

Another large leaf magolia, Magnolia tripetala x obovata, is similar in most respects; however, it features a broad, round form and is a bit more formal in the landscape. This magnolia can be found in the Waterfall Garden.

PHOTO: Magnolia tripetala x obovata
The blooms of Magnolia tripetala × obovata can be up to a foot across.

Campsis radicans is a native vine with large, orange-red, trumpet-shaped flowers all summer long. The flowers are a hummingbird magnet, which just adds to the tropical allure, and are available in numerous colors, including red, orange, and yellow. This is a large, growing vine so give it room to grow. It does tolerate pruning but blooms best when allowed to grow uninterrupted. Even the seed pods are ornamental, looking almost like green bananas hanging from the flower clusters. Look for it in the Waterfall Garden, and the fence surrounding the Graham Bulb Garden, where we have red and yellow varieties mixed together.

PHOTO: Campsis radicans
Campsis radicans grows in the Waterfall Garden.
PHOTO: Asimina triloba
Pawpaw (Asimina triloba) fruits hang high in the tree.

Another native plant that wouldn’t look out of place in the rain forest is the pawpaw tree (Asimina triloba). This native tree has green leaves that can reach a foot long. It’s a beautiful understory tree that will grow well in dappled shade with ample moisture (but never standing water). However, the real reward with pawpaws are the fruit. These large fruits have an incredibly tropical flavor, like a mix of mango, pineapple, and bananas. The fruit are among the last to ripen in the late summer and well worth the wait. To get a good crop of fruit, make sure to plant two varieties.

Pawpaws also get beautiful golden fall color, which only adds to their appeal. One note of caution however: the trees can sucker, so make sure to plant your pawpaw somewhere where this isn’t a problem, or make sure to remove the suckers as they sprout. Look for pawpaws in the Bulb Garden, Regenstein Fruit & Vegetable Garden, and Native Plant Garden.

And finally, what is a tropical garden without lush fragrances? Clethra alnifolia is a hardy shrub that thrives in partial shade and boasts intensely fragrant blooms in late summer.

PHOTO: Clethra alnifolia 'Rosea'
Clethra alnifolia ‘Rosea’ has cheerful pink flowers that hummingbirds love.
PHOTO: Clethra alnifolia 'September Beauty'
Clethra alnifolia ‘September Beauty’ is one of the latest-blooming summer-sweet cultivars.

Clethra flowers have a rich smell similar to gardenia, but with spicy undertones. The flowers are tall spikes of white or pink and are a magnet for pollinators such as honeybees and hummingbirds. With careful planning, you can mix varieties of clethra and have blooms that last from mid-July through late August. Several varieties of clethra can be found in the Sensory Garden.

See Brazil in the Garden through October 15, 2017.


©2017 Chicago Botanic Garden and my.chicagobotanic.org