Cheyenne Garden Gossip

Gardening on the high plains of southeastern Wyoming


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Bulb forcing brings spring indoors mid-winter

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This classic bulb-forcing vase holds a hyacinth bulb. Photo by Barb Gorges.

Published Oct. 15, 2017, in the Wyoming Tribune Eagle, “An indoor spring…during the winter.”

By Barb Gorges

It’s the season for buying spring-blooming bulbs. But not all of them need to go in the garden—at least not right away. Some of them can be kept back for forcing.

Bulb forcing allows you to enjoy crocus, the small iris, hyacinth, daffodils and even tulips indoors earlier than they bloom outside. Think of them as a deep winter gift to yourself, or for someone else.

Cheyenne Botanic Gardens director Shane Smith recently gave me background on the practice and a few tips.

The science and history

Smith said the trick is to use bulbs from temperate climates that need winter—such as the bulbs we plant in our gardens for spring bloom. They can get by with a shorter winter, or artificial cooling period, to bloom. Bulb growers in Europe started taking advantage of this about 300 years ago, as relayed by Patricia Coccoris of Holland in her book, “The Curious History of the Bulb Vase.”

The timing

Buy spring-blooming bulbs now. Bulbs ordered from catalogs begin shipping here around the beginning of October because bulbs normally need to be planted outdoors when the soil cools, but before it freezes in December.

For bulb forcing, figure 12 weeks minimum of “cool treatment,” however tulips need 13 weeks or more. Once the minimum is met, you can stagger when you start warming up the bulbs. You can aim for specific bloom times during our cabin fever months, January through March, or maybe even later into spring when we get those depressingly late, tulip-breaking snow storms.

The best bulbs

Smith said he used to tell people to buy the premium-sized bulbs for forcing, but now he thinks he gets more bloom for his buck with the smaller grades of bulbs. Premium hyacinth bulbs go for more than a dollar apiece in the John Scheepers catalog, but you might find smaller bargain bulbs and have more, if only medium-sized blooms, for the same amount.

Smith said some varieties of bulbs are easier to force and bulb catalogs often will mention which ones. Varieties seem to go in and out of vogue so don’t be surprised if Smith’s are hard to find.

Hyacinth is the classic forcing bulb, growing 10-12 inches tall. Each stalk is covered in tiny florets. Smith looks for Pink Pearl, Queen of the Pinks, White Pearl, L’Innocence (white), Blue Jacket, Delft Blue and Blue Giant.

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Crocus-sized bulb-forcing vases are harder to find. Photo by Barb Gorges.

All varieties of crocus force well. Smith’s favorite varieties are Remembrance (purple), Blue Ribbon, Giant Yellow and Jeanne d’Arc (white). Only 4-5 inches tall, they are usually planted as a mass.

Iris reticulata, though related to the summer-blooming bearded iris, grows only 4-6 inches high. Recommended for rock gardens, mine bloomed outside at the end of last February, but it would be nice not to have to brave winter winds to enjoy it. Smith said all the varieties force well. Scheepers lists eight ranging in color from white to blue to deep purple, all marked with a bit of yellow.

Almost any daffodil (narcissus) will work well for forcing, said Smith. The popular Paperwhite narcissus, however, is a tropical bulb, so it doesn’t need cooling.

Tulips, said Smith, are the hardest to force. They need the longest cooling time, minimum 13 weeks. They also may get floppy and need staking. Look for the earliest varieties, those that would otherwise bloom outdoors here (winter-hardiness zone 5) in April.

There are a variety of other, more difficult spring-blooming bulbs to experiment with: snowdrops, grape hyacinth (muscari) and squill (scilla).

Bulb-forcing vases

Bulb-forcing vases are not easy to find this fall. Your best bet is Amazon or eBay. These vases, usually glass, are pinched near the top, providing a cup for the bulb to sit suspended so that only its base touches the water. You watch as the roots grow to fill the rest of the vase and the flower stem sprouts. For this forcing method, you can cool just the bulbs in your refrigerator for the recommended time. Be sure hyacinth bulbs don’t touch produce.

If you are lucky enough to find a bulb forcing vase, remember to change the water regularly.

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These hyacinth bulbs have been potted up and will be set in a 2-foot deep trench in the vegetable garden and mulched with straw or pine needles for their 12-week “cool treatment.”  Small bulbs, like crocus, need a half inch of soil covering them. Photo by Barb Gorges.

Potted bulbs

Smith pots his bulbs. Without a cellar between 35 and 45 degrees, he instead buries the pots in a 2-foot-deep trench in his vegetable garden. He then backfills the trench with straw or pine needles. The mulch allows moisture to percolate down, whether the bulbs are watered by hand or by snow, and allows in air.

Pots can be plastic or clay. However, if you have a fancy one, you may want to use it as a cache pot in which you insert the utilitarian pot that was buried.

Put only one type of bulb in a pot because different types sprout at different rates.

The depth of the pot should allow 2 inches or more of potting soil under the bulb with the bulb tip just a little below the rim of the pot.

Smith said regular packaged potting soil will do. Potting soil can be very dry, so mix it with water in an old dishpan or bucket before spooning it into the pot as the layer that will be under the bulbs. Then set the bulbs on top, right side up. The root end can have bits of root left and the shoot end is usually pointier.

You can pack the bulbs in, nearly shoulder to shoulder, leaving just a little space between them. Then fill in with more potting soil. Smith said the top third of the bulb can be left exposed, but crocus and iris bulbs need to be covered a half inch deep.

Label the pot so you remember what’s in it—especially if you do more than one kind. Mark where you bury the pot. And mark your calendar for when to bring the pot in.

Chill out

While the potted bulbs are chilling in the dark, make sure the soil doesn’t dry out. You may need to lift the mulch and water once a month if it’s a dry winter.

Coming in from the cold

When you bring a pot in, Smith recommends putting it in a dim room at 60 degrees or cooler until the shoots are a few inches tall. Then move it to a bright window and 65 degrees. “Buried to blooming” may take two weeks. Turn pots every day to keep plants growing straight.

Flowers can last a week or two. Once in bloom, you can prolong it by setting the pot farther from the window and keeping the room’s temperature at 65 degrees.

Afterward

The advantage to planting forced bulbs in potting soil is that you can give them a second life. Cut back the spent flowers and keep watering until the leaves turn yellow. Plant the bulbs out in the garden when the soil thaws, where they might bloom again in two years.

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Iris reticulata bulbs were forced to bloom indoors one spring, then replanted outside in the garden in early summer where they bloomed the next spring. Photo by Barb Gorges.

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Iris farm shares beauty, growing tips

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A visitor walks a corner of  C and T Iris Patch last June. Photo by Barb Gorges.

Published April 30, 2017, in the Wyoming Tribune Eagle.

Iris farms, sharing beauty and growing tips

By Barb Gorges

There is an annual flower phenomena less than an hour south of Cheyenne, just east of Eaton, Colorado, from mid-May through early June. And after you find it, you might think you’d been to Eden.

It’s thanks to a tradition among iris farms to open to the public while the iris are blooming. Last year was my first visit to C and T Iris Patch’s acre of beauty, and it won’t be my last.

There is a gap between the spring bloom time and the best time to transplant iris—July into August—but Charlette Felte, of C and T Iris Patch, takes pity on spring visitors and allows them to take home select plants. I bought several and as per her instructions, cut the blooms and put them in a vase, then trimmed the leaves and planted the rhizomes (fat root-like appendages) in a sunny spot.

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Charlette Felte has a special patch of iris for spring visitors to buy from if they can’t wait for the traditional July-August transplanting season. Photo by Barb Gorges.

With 3,000-4,000 visitors, it’s good everyone doesn’t succumb to immediate gratification and can wait until orders are shipped in summer. If you can’t visit, the color photos in the online catalog are nearly as inspiring.

When Felte reached retirement age, she announced to her husband Tim that she wanted to move to the country to raise iris.” Fine,” he said, “find some land.” Two days later Felte had picked out a place.

Felte knew a lot about iris already. Growing up, her father would send her and her siblings down the street to help an elderly neighbor who had an iris garden.

“I thought they were the prettiest flowers,” Felte said.

Variations

C and T Iris Patch opened in 2000. It now carries 3,200 varieties of iris. The largest category is the bearded iris (the beard being the fuzzy patch on the falls—the petals that bend downwards). Within bearded iris there are classifications based on height.

[Here are the classes of bearded iris beginning with the earliest to bloom: Miniature Dwarf Bearded, Standard Dwarf Bearded, Intermediate Bearded, and then blooming at the same time as the Tall Bearded (mid-late spring), Border Bearded and Miniature Tall Bearded.]

If you are lucky, your iris may rebloom in the fall—when temperatures resemble those during the spring bloom. Some varieties are identified as rebloomers because they have a propensity for it, but it isn’t something to count on.

Now if you think all iris are blue or yellow, you really need to check out what’s available, either online or during bloom time. There’s also peach, orange, pink, brown, red and violet, and some are bi-colored, tri-colored, spotted, striped, and edged with accent colors. And for some reason, flower breeders are always trying for “black.”

The names people dream up for each new hybrid are sometimes beautiful, “Come Away with Me,” “Kiss the Dawn,” “Mist on the Mountain.” Sometimes they make you laugh “All Reddy” (a red iris), “Awesome Blossom,” “Coming Up Roses,” “Darnfino,” “Get Over Yerself,” “Got Milk” (all white and ruffled). And some might be a bit naughty: “Sinister Desire,” “Sunrise Seduction,” “Hook Up.” Or named for someone, usually a woman, “Sarah Marie,” “Raspberry Rita,” “Evelyn’s Echo.”

As I was perusing the catalog this winter, I noticed that each description mentioned the date the hybrid was introduced. The fun of breeding new hybrids actually goes back centuries to the origins of these iris in Europe, North Africa and Asia. North America has wild iris, but they usually prefer swampy conditions.

In Felte’s catalog there are varieties from the 1930s: “Rhages,” “Wabash,” and “William Setchell,” and from 1912, “Romero,” and the oldest, from 1904, “Caprice.” Among other kinds of plants, the older varieties are not as disease resistant. However, Felte said that the older iris hybrids, especially from the 1950s through 1980s, are hardier. The newer, rufflier, lacier, frillier, don’t winter as well. Plus, they don’t have as much fragrance.

Iris photos taken at C and T Iris Patch by Barb Gorges.

Growing iris

Iris are not fussy plants. They prefer drier conditions (they will rot if they aren’t dry enough) so they fit with today’s water-smart gardens.

Felte also recommends her Wyoming customers not choose the tallest, the 40-inchers, because they take so long to bloom, and Cheyenne is already two weeks behind Eaton. The delay is probably due to a combination of Eaton being 1,200 feet lower, 45 miles south, and having sandier soils that warm up faster in spring.

Iris leaves grow in fan arrays. In July, when irises are normally dug up for transplanting, the fan is trimmed to a 6-inch tall diamond. Otherwise, leaves are not trimmed until the following spring.

The rhizomes are covered with an inch of soil, up to the point where the leaves turn from white to green. Felte recommends giving the transplants an inch of water the first time, and then about half an inch per week until mid-September. Deep watering is better than frequent shallow watering.

Felte recommends rabbit feed (pellet form) for fertilizer, which is high in phosphates and other nutrients iris need for good blooms. They need very little nitrogen. The best time to fertilize is mid-to-late March, and again in July for the reblooming varieties or plants newly divided. Felte warns on her website to never use manure.

Trim the flower stalks after blooming to keep the color of the bloom true next year. Trim dead leaves away after winter, Felte said.

In three or four years, your irises will have multiplied and need to be dug up and thinned to keep them blooming. You can either increase the size of your iris garden or give the excess fans to friends.

New hybrids

While bees will pollinate iris and cause seed pods to form, Felte recommends removing them. Unless you have controlled conditions, the seeds will not grow true to the parent plant.

I asked Felte if she has ever registered her own hybrids and she said no, it’s about a 10-year-long process. First, you must provide enough seed true to the hybrid for 75 growers around the country and overseas to grow it out. They keep records for four years and submit them to the American Iris Society which will decide if your hybrid is different enough from all the registered varieties. [Some of the larger iris farms, such as Schreiner’s Iris Garden in Oregon, contribute new hybrids annually.]

Area iris farms open this spring

C and T Iris Patch will be open to the public this year May 20 through June 11, 9 a.m. – 6 p.m., seven days a week, at 20524 WCR 76, Eaton, Colorado, at no charge. The website, www.candtirispatch.com, has extensive information about growing iris, and they are ready for online orders as are other Colorado iris farms:

In Boulder, Colorado, Longs Gardens will be open to the public now through June 11, seven days a week, 9 a.m. – 5 p.m., at 3240 Broadway. See www.LongsGardens.com for more information.

In Denver, check the website for Iris4U Iris Garden, 2700 W. Amherst Avenue, for their public hours, www.iris4u.com.

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C and T Iris Patch in Eaton, Colorado, grows a wide variety of bearded iris and allows the public to visit during the May-June blooming season. Photo by Barb Gorges.