A Year in Bulbs: Part Two

Things move quickly in the bulb garden in the spring!

In three weeks, we’ve already seen the “little blue bulbs” (Scilla and Chionodoxa) come and go, the first of the species tulips burst forth with color, and the foliage fill out, creating a rich, green backdrop, allowing the flowers to shine. Even with our cold spring, we’ve already had a month of flowers—which goes to show just how tough these plants really are. We’re on our third flush of flowers while many other gardens are still just waking up for the season.

PHOTO: A view of the south path, dotted with the blues and reds of scilla and tulips.
The south path on April 21, showing the last of the Scilla and Tulipa batalinii ‘Bronze Charm’

The little blue bulbs are making way for the most popular and well-known of the bulbs; the daffodils (Narcissus) and hybrid tulips. We’ve also got many types of Fritillaria, Corydalis, and Muscari adding unique colors and forms to the display. The foliage is filling out, creating a lush oasis of green in an otherwise still-dreary spring.

PHOTO: A view of the south path, now filled with narcissus.
The south path on April 30—note how the Scilla and tulips have given way to Narcissus, with many more flowers waiting to burst forth
Photo: A combination of differently-shaped blooms in purple and white make a beautiful contrast.
Corydalis solida ‘Purple Bird’ and Muscari aucheri ‘White Magic’
PHOTO: Closeup of Muscari 'Pink Sunrise' blooms.
Muscari ‘Pink Sunrise’

Look closely as you walk along the paths, and you’ll see many unique flowers, such as several varieties of Erythronium and Fritillaria of all different sizes and colors.

PHOTO: A closeup of Fritillaria imperialis 'Aureomarginata'.
Fritillaria imperialis ‘Aureomarginata’
PHOTO: Closeup of Erythronium hendersonii in bloom.
Erythronium hendersonii

On May 1, we had our first Meet the Horticulturist for the season. I had the opportunity to lead a group of visitors around the Graham Bulb Garden and highlight some of the most unique and exciting things in bloom. Some visitor favorites included Corydalis varieties with their jewel-toned flowers and soft cushions of blue-green foliage; the cheerful spikes of blue, white, or palest pink Muscari; and dwarf Iris ‘Evening Shade’, which is a new hybrid Juno iris, with a unique growth habit, that looks very much like a miniature corn plant. Another plant that really wowed the visitors was the variegated crown imperial fritillary (Fritillaria imperialis ‘Aureomarginata’).  

Meet the Horticulturist events are a great way to get a more in-depth view of some of your favorite gardens. We’ll be featuring four more throughout the summer, with various other gardens as the highlight. Come talk with us!

PHOTO: Narcissus in the Bulb Garden.
Narcissus are just starting to put on a show.

PHOTO: Closeup of dwarf Iris 'Evening Shade'
Iris ‘Evening Shade’

©2014 Chicago Botanic Garden and my.chicagobotanic.org

Bulbs for Fall and Winter Interest

Just when the hostas, lilies, and other garden perennials are going to bed for the season, these bulbs are waking up. 


PHOTO: Closeup shot of the leaves of Arum italicum 'Jet Black Wonder'
Arum italicum ‘Jet Black Wonder’ has unique black spots and pink- tinged flowers.

Arum first emerge in the late fall. The broad, arrow-shaped leaves of Arum italicum are highly ornamental and sturdy—quickly perking up after hard freezes, providing a welcome spot of green in the winter garden. Throughout the winter, they remain green and full, providing a welcome burst of green in the winter garden. In the late spring, they send up creamy white flowers that resemble calla lilies (Zantedeschia sp).

Soon after flowering, the leaves die for the season, revealing showy, fruiting stalks of bright red, highly ornamental berries. While these berries are quite attractive, do be aware that they’re poisonous and should be planted where they won’t tempt any children or pets to eat them. If located in an ideal site, they will reseed and form a ground cover. There are dozens of varieties, each with its own unique leaf patterns.

PHOTO: Wilted Arum italicum in the Garden.
Arum italicum ‘Mamoratum’ after a cold snap.
PHOTO: Arum leaves look back to normal after warming up following a heavy frost.
This is the same Arum italicum pictured above after recovering from the frost.

Fall cyclamen

PHOTO: Cyclamen leaves emerge from the ground in spring.
Cyclamen hederifolium ssp. crassifolium

There are two primary types of cyclamen that are hardy in Chicagoland. These are the fall-blooming Cyclamen hederifolium and spring-blooming Cyclamen coum. The fall-blooming Cyclamen hederifolium have ivy-shaped leaves with stunning silver patterns and small, windswept-looking flowers. Cyclamen coum blooms in the late winter or early spring, and has heart-shaped leaves with silver patterns.

Both plants grow their leaves in the fall and carry them through the winter before going dormant in the spring. Their flowers range in color from pinks and lavenders to white. Cyclamen prefer a shady spot that doesn’t stay wet; otherwise the bulb will rot.

A great place to plant cyclamen is under deciduous trees, where the leaf canopy will protect the dormant tubers from excess rain. If sited properly, they will reseed and form a ground cover.

PHOTO: Cyclamen bloom through the leaf litter in Home Landscape Garden.
Fall cyclamen (Cyclamen hederifolium) blooming in Farwell Landscape Garden.

Fall allium

Among the latest-blooming bulbs are the often overlooked Allium thunbergii ‘Ozawa’ and A. thunbergii ‘Ozawa Alba’.  These relatives of onions form grassy clumps that look green and fresh all summer long and suddenly burst forth with small clusters of flowers resembling pink-and-purple lollipops in late October, often continuing until mid-November. (As of November 17, these were still going strong in the Farwell Landscape Garden, even after hard rain, several hard freezes, and a light snowfall!) Allium thunbergii prefers to be located in a sunny, well-drained location, where it will continue to grow and thrive for many years. These are great plants for a sunny rock garden, where they provide a welcome shot of color at the end of the season.

PHOTO: Purple fall onions blooming in the Garden.
Allium thunbergii ‘Ozawa’
PHOTO: White fall onions in bloom.
Allium thunbergii ‘Ozawa Alba’

©2013 Chicago Botanic Garden and my.chicagobotanic.org

It’s so easy: Plant garlic now

PHOTO: The blooming flower stalk of Sicilian honey garlic.
Reminiscent of Fritillaria, Sicilian honey garlic (Nectaroscordum siculum) is a beautiful ornamental allium selection.

Garlic is so easy to grow that the instructions could be just one sentence long:

In October, separate a large head of garlic into individual cloves, and plant 3–4 inches deep in well-amended, well-drained, and well-mulched soil until harvest next July.

But let’s dig a little deeper into that sentence for a few tips on growing a gorgeous garlic crop.

In October… Fall is the season for planting garlic in our area. Wait until the first light frost to plant, and don’t worry if you see a few garlic sprouts popping up before winter sets in.

…separate a large head of garlic… Which garlic to plant? Experiment with different varieties to find the flavor you like best. Nurseries and seed catalogs offer seed garlic (grocery store-bought garlic isn’t as reliable as seed). There are two main types:

  • Hard-necked varieties grow well in northern climates like ours, where winter is cold and spring is long. As the name implies, hard-necks produce a rigid flower stalk  or “scape” with aerial bulbs. The scape should be cut off at about 10 inches long so that the plant continues to put its energy into the underground bulb. Don’t toss the scapes—eat them, instead, in soups, sautés, etc. ‘Music’, ‘German Extra Hardy’, and ‘Chesnok Red’ are hard-neck varieties known for their wonderful, complex flavors.
  • Soft-necked varieties don’t produce scapes; their soft foliage can be braided for easy hanging/storage. While soft-necks flourish in the South, some varieties, such as ‘Inchelium Red’, can be successfully grown here.
PHOTO: A basket of garlic, with each bulb labeled with its cultivar name.
Try growing different garlic varieties to find the flavor you like best! Photo: Lisa Hilgenberg

…into individual cloves… To grow the largest garlic heads, plant only the largest garlic cloves, and leave the papery “tunic” intact. Cloves can rot without their protective tunic! Hard-necked garlic heads yield large cloves in small numbers (often 4–6), while soft-necked garlics bear more numerous cloves, often in several layers.

…and plant 3–4 inches deep… Plant cloves roots down, points up, about 6–8 inches apart.

…in well-amended… Soil prep is key to a successful crop, no matter what type of soil you have. Garlic is a heavy feeder, so the soil needs to provide plenty of nutrients, air, and water. Amend your soil with compost or well-aged manure until it feels loose and airy. Aim for a neutral pH of 6.5.

…well-drained… While it needs to be kept watered, it is important to plant it in a spot where the soil is moist, but not too wet. Garlic doesn’t like “wet feet.” Once foliage appears in spring, water consistently (about 1 inch per week) until two weeks before harvest in July.

…and well-mulched soil… After a hard frost, cover the garlic bed loosely with a thick layer of mulch (about 6 inches of straw, leaves, and/or grass clippings). Mulch acts like a blanket over the bulbs and soil, holding in moisture and keeping down weeds, which can easily overwhelm and outcompete garlic. Leave mulch intact through the season—garlic sprouts will make their way through it—but remove it when things warm up in the spring.

…until harvest next July. In July, garlic foliage begins to turn brown, signaling that harvest is near. Wait until just five green leaves are left on the plant. Then use a pitchfork to gently loosen the soil beneath the bulbs and bring them to the surface. Resist the urge to pull them by their stalks, taking care not to damage the papery tunic! Brush off most of the dirt, then allow your harvest to cure:

  • Spread out the bulbs (with foliage intact) on screens, or tie them in loose bundles and allow to dry in a shady, well-ventilated area, such as a back porch or garage.
  • Do not wash the bulbs to remove soil! Leave them undisturbed for 4–6 weeks, during which time they’ll dry out completely. 
  • After curing, trim the roots and cut stalks to about 1 inch from the bulb. 
PHOTO: Garlic bulbs in storage on a shelf (with artful lighting).
Curing garlic: also a wonderful photographic still life. Photo: Karen Zaworski

Many of these same cultural practices follow for shallots and other allium varieties.

One last tip: Store your garlic at 50 to 70 degrees—but not in the refrigerator, as cold makes bulbs sprout early! With proper curing and storage, your bulbs should last about four months.

©2013 Chicago Botanic Garden and my.chicagobotanic.org

Green Thumbs at Work

What it takes to plant 26,000 tulip bulbs in the Crescent Garden in just 3 hours:

  • 4 dozen doughnuts
  • 2 boxes of coffee
  • 2 gallons of orange juice

And 20 dedicated volunteers and staff fueled by the above.

Bulb planting
By 11:00 a.m., 26,000 tulip bulbs were planted in the Crescent Garden last Thursday.

It’s time to plant bulbs for next spring, and the weather’s cooperating nicely. In your yard, plant tulip bulbs 6-8 inches deep in well-drained soil. Remember, bulbs will rot where there’s too much water from gutters, irrigation, or poor drainage. Plant plenty: tulips look wonderful in clusters, in drifts, and in vases all around the house next spring!

Horticulturist Benjamin Carroll has a great video on how to plant bulbs at home. Check it out (along with other planting information) here.

Baby Birds and Bulbs on the Green Roof Garden

Emily Shelton shows us what’s blooming on the Green Roof Garden this spring. She also talks about the ground nesting kildeer and babies that were just born. Emily will give tours and answer your questions about the Green Roof Garden at World Environment Day on June 4, 2011. Ask a Horticulturist, Green Roof Garden is from 11 a.m. to 4 p.m. at the Daniel F. and Ada L. Rice Plant Conservation Science Center. Visit http://www.chicagobotanic.org/wed2011/greenroofgarden.php for more information.