Archives For Grunsfeld Children’s Growing Garden

One of our favorite insects at the Chicago Botanic Garden is the praying mantis. So we were very excited to obtain an egg case earlier this spring. We decided to keep it indoors so we could watch it hatch, and then release the newly hatched insects into the Garden.

PHOTO: Preying mantid egg case on a twig.

About 100 praying mantises emerged from this ootheca and were released into the Grunsfeld Children’s Growing Garden.

A praying mantis egg case is called an ootheca (pronouned oh-uhTHEE-kuh). The plural is oothecae (oh-uh-THEE-see). The ootheca was produced by a female praying mantis last fall. She laid her eggs in this foam of protein that hardened around a stick and protected the eggs through the winter. The eggs usually hatch in mid-June to early July. The half-inch-long immature praying mantis nymphs resemble the adult, but they do not have wings. 

PHOTO: Hundreds of baby mantids pour out of an egg case.

Colorless praying mantis nymphs emerge from the ootheca all at one time. During their first hour, they darken in color to blend in with their surroundings.

After our praying mantises hatched inside an insect cage, I discovered that a bed of false sunflower plants (Heliopsis helianthoides) in the Grunsfeld Children’s Growing Garden was infested with red aphids. I released the praying mantises, and the hungry babies immediately began to feed.

PHOTO: Mantis nymphs on the head of a Rudbeckia flower covered with aphids.

At first, the praying mantis babies seemed a little bewildered by their new surroundings, but they quickly acclimated.

PHOTO: Mantis nymph on a flower stem eyes aphids—a tasty meal.

This mantis held very still as it eyed its prey.

PHOTO: A row of mantis nymphs on a leaf face a stem covered with red aphids.

These four little mantises lined up and stared at the aphids that would certainly become lunch soon.

It wasn’t exactly aphid carnage—much to the disappointment of our eighth grade Camp CBG helper, Joshua, who assisted me with the release—but the young predators did appear to enjoy their first meal.  

PHOTO: Preying mantis on liatris bloom in August.

By the end of August, some of our little friends will be as big as this praying mantis (and just as hungry)!

It may surprise you to know that although it looked like a bad infestation, aphids are not really a big problem for the plants. When they are very abundant, it does not take long for natural predators like praying mantises and ladybugs to find them and move in for a feast. Predatory insects will take care of the problem if you are patient and let nature take its course. If aphids show up in your garden and they bother you, we recommend hosing them off with water rather than using an insecticide, because chances are pretty good that there are beneficial insects on your plants, too. Hosing with a strong jet of water will knock off all the bugs and kill most of the aphids, but it won’t be as devastating to the mantises or other beneficial insects as poison.

We have placed praying mantis oothecae in the Regenstein Fruit & Vegetable Garden and Elizabeth Hubert Malott Japanese Garden, as well as in the Children’s Growing Garden, to ensure that there will be a population of our favorite insect for you to find. Many of them will survive on aphids and other insects they capture and devour on our flowers, and they will grow up over the summer. The next time you visit, stop by and see if you can find them helping our plants remain healthy and less bothered by pests.

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Have you seen the sunflowers in the Grunsfeld Children’s Growing Garden this month? Let’s take a closer look to see what’s going on.

PHOTO: Sunflower nodding down toward the ground.

Many of the blossoms have lost their yellow petals and are bending down.
We need to take a closer look.

PHOTO: Very close up picture of a sunflower.

Just a little closer …

PHOTO: Extreeme close up of the middle of a sunflower, showing the tiny florets and sunflower seeds.

There!

Now you can see that one sunflower is actually made of hundreds of very small flowers. Notice the tiny, yellow, pointed petals of the individual flowers. Each blossom produces one seed. You can see the seeds where they have matured at the top edge of this sunflower. Can you find the spot where one seed is missing? Perhaps it fell out or was eaten by bird.

Sunflowers are what we call “composite” flowers, so named because they are composed of many florets growing so close together they appear to be one flower. If you look carefully at the arrangement of the flowers and seeds, you might notice a spiral pattern.

Other composite flowers you may know are daisies, dandelions, and mums. There are many composite flowers blooming at the Chicago Botanic Garden right now. Come for a visit to check it out, and bring your favorite magnifier so you can take a closer look at the real thing.

Visit chicagobotanic.org/learningcampus/growinggarden for more information on the Grunsfeld Children’s Growing Garden.