Dazzling dahlias

If a rainbow of flowers is your goal, the answer could be dahlias.

We're not saying dahlias are an easy path to gardening glory, but they will get you there.

The best idea of what is available in this magical world will be at the American Dahlia Society's National Show Saturday and Sept. 9 in St. Charles.

"It's spectacular, spellbinding when you walk into a show hall full of dahlias," said Jerry Landerholm of Lombard, president of the national society, which has 2,400 members.

As many as 3,000 blooms will be displayed, as well as photographs and arrangements.

A big benefit is that both admission and parking are free.

Dahlias bloom in red, orange, yellow, lavender, purple, pink and white.

Consider the luminescent purple Clara Marie and the brilliant white Brookside Snowball.

And some flowers are combinations of two shades. Mingus Nicole has gold flaring into purple edging, while Jessica does a similar effect with gold and red.

Beware. The Central States Dahlia Society, which is hosting the national show, wants to lure you into becoming a dahlia fanatic, Landerholm said.

Traditionally, dahlias are celebrated for the size of their colorful blooms -- which can be more than 10 inches in diameter.

Generally, dahlia plants grow 4 feet tall to support these flowers, and some are taller.

However, more energy has been put into creating attractive, smaller dahlias for gardeners who work with containers or small yards.

Frank Campise, known for the variety of flowers in his Arlington Heights dahlia garden, treasures blooms for their perfect form.

Size does not inspire him; he grows several different styles of dahlia flowers -- from round ones shaped like pompons to spikier looks.

The blooms of Rejman's Polish Kid are round and smooth and not very large in dark red with white tips, for example.

Dahlias used to flower in September, but now with a cutting method of propagation they can bloom all summer, Campise said.

Dahlias require sunshine, rich, slightly acidic soil and lots of water. That makes this rainy year a good one for the flowers, but they also like cool nights.

Extra buds need to be plucked off to put the plants' energy into showy blooms. Insects such as Japanese beetles can be a problem. And then there is a virus discussion on the Web site of the American Dahlia Society.

Perhaps most importantly the tubers must be dug up and stored over the winter in a space that stays about 40 to 50 degrees, such as a garage that doesn't freeze.

Rolland Hein, a retired professor from Wheaton College who gardens in St. Charles, uses compost rich with horse manure.

He loves red dahlias like Midnight Dancer or Dare Devil, and those with a mix of a few colors like Gladiator's yellow with red streaks.

But he plants from seeds the less showy, shorter bedding dahlias in the middle of one of his beds. Bishop's Children produce simple orange blooms in his garden.

Dahlias can be tricky, but here are several Frank Campise of the Central States Dahlia Society says are easy to grow:

•Kelvin Floodlight grows large and yellow.

•Spartacus is red, and Campise said it will grow as large as a basketball.

•Rejman's Polish Kid produces smaller red and white blooms.

•Peaches & Cream has a gorgeous delicate color.

If you go

What: American Dahlia Society's National Show

When: Noon to 5 p.m. Saturday and 9 a.m. to 4 p.m. Sept. 9.

Where: Pheasant Run Resort, three miles west of Route 59 on Route 64.

Admission: Free

Details: (847) 231-5075 or Dahliadan@ameritech.net

Besides sparking up a garden, dahlias produce great cut flowers.

"People fall in love with dahlias," Hein said. "So many don't want to do the work. It takes work."