If you love both <a href="https://nameberry.com/list/317/unique-baby-names">unique baby names</a> and flower names for girls, Amaryllis might be a perfect choice for you. 

A showier flower name than Lily, but in the same botanical family, Amaryllis is not as outre as it might at first sound. It was used in Greek poetry as the appellation of pure pastoral beauties; Amaryllis is the heroine of Virgil's epic poem Ecologues, after whom the flower was named. 

Other references are characters in the George Bernard Shaw play Back to Methuselah and The Music Man. James Bond-creator Ian Fleming had a half sister named Amaryllis Marie-Louise Fleming, who was a noted British cellist.

Amaryllis

Anemone is a floral name that relates to the ancient Greek myth of the famous love story of Aphrodite and Adonis, in which Aphrodite transforms her wounded lover's blood into a flower, the crimson anemone, whose blossoms are opened by the wind — accounting for its other name, windflower.
 This makes an interesting, if challenging, choice for someone seeing an unusual flower name.

Anemone

Azalea is one of the fresher flower names, along with Zinnia and Lilac, that are new to the name bouquet — in fact, it entered the Social Security list for the first time in 2012. So if Lily and Rose are too tame for you, consider this brilliant pink springtime blossom with a touch of the unusual that has been growing in popularity. 
 Azalea is the name of the princess heroine of the novel Entwined, and, most recently, is connected to musical artist Iggy Azalea.

Azalea

Alcea

Astrantia

Babiana

Bellis

If you love Calliope and Callista, you'll love Calanthe, which combines the trendiness of the Greek 'cal' names with the equally fashionable "the" ending (like Xanthe and Evanthe) and a connection to the beautiful Christmas Orchid. Color Calantha one of the more unusual and captivating <a href="https://nameberry.com/list/412/christmas-baby-names">names for Christmas babies</a>.

Calanthe

Calla is a lily name that is much more distinctive and delicate than Lily. Rarely heard today, it did appear in the popularity lists in the last decades of the nineteenth century.
 Calla is the eponymous heroine of the Rebecca Wells novel The Crowning Glory of Calla Lily Ponder, and there's an English rock band called Her Name is Calla.
 Actress Mare Winningham named her daughter Calla way back in 1987.
Sound-alike Cala is an Arabic name meaning fortress.

Calla

Camellia is a rare flower name with distinct roots related to the Camille/Camila group and has varied associations to the moon, water, wealth, and perfection. It could be thought of as a floral replacement for Amelia. 
 The attractive flowering tree was named by Linnaeus for the Moravian Jesuit botanist Georg Joseph Kamel and has been used, if sparingly, as a first name since the 1930s.
 In the language of flowers, the camellia denotes admiration and perfection, and it's the state flower of Alabama. The Dumas novel The Lady of the Camellias is the basis of the opera La Traviata and the Garbo film Camille.

Camellia

Flower name that sounds a bit too much like a disease. 

Clematis

Chrysanth

Coelia

One of the flower names, used occasionally in Britain (where it's pronounced DAY-lee-a). It seems to have recovered from what was perceived as a slightly affected la-di-dah air. The flower was named in honor of the pioneering Swedish botanist Andreas Dahl, which means dale.
 In the Victorian language of flowers, Dahlia denotes elegance and dignity.
 In P.G. Wodehouse's Jeeves stories, Dahlia is Bertie Wooster's more sympathetic aunt, described as being constructed along the lines of Mae West. Reporter Dahlia Lithwick covers legal matters for the online magazine Slate.

Dahlia

Delphinium

Disa

A rare, free-feeling flower name for the parent who wants to move far, far beyond Rose and Daisy. Named for German physician Friedrich Freese.

Freesia

Fuschia

Like Violet, Lavender and Lilac, Ianthe is a purple flower name. Chosen by the poet Shelley for his daughter, Ianthe has a poetic, romantic, almost ethereal quality. In the ancient myth, she was the daughter of Oceanus, supreme ruler of the sea, and also a Cretan woman so beautiful that when she died the Gods made purple flowers grow around her grave.
 Iantha is also used.
 Ianthe was a favorite of the pastoral poets of the seventeenth century and then again in the early nineteenth. She appears in the works of Shelley, Barbara Pym and Georgette Heyer. Writer Richard Brautigan named his daughter Ianthe.

Ianthe

This unusual Greek flower and color name has gained considerable recent attention via actress Ione Skye, who is the daughter of sixties folksinger Donovan.
 Ione was one of the fifty sea nymphs — Nereids — in ancient Greek mythology.
 Parents attracted to newer I-names like Isla might want to consider the distinctive Ione. The English pronunciation usually starts with the long I, while in the Latin languages such as Italian it starts with the long E sound.

Ione

Ionantha

Lavandula

Lepanthes

Magnolia, a sweet-smelling Southern belle of a name made famous via the iconic Edna Ferber novel and musical Showboat, is one of the latest wave of botanical names, along with unexpected blossoms Azalea and Zinnia. It is named for French botanist Pierre Magnol.
 Magnolia has been chosen for his daughter by Adrian Young of No Doubt—which happens to be a fabulous baby-naming consortium as well as a great musical group.
 In Showboat, the Magnolia character goes by nicknames Noa, Nollie, and Maggie.
 Magnolia charted on the popularity list almost every year from 1880 to 1940, topping at Number 420 in 1909—but it's now making a comeback.
 Magnolia Breeland is a character on the TV show Hart of Dixie, who happens to have a sister named Lemon and a father named Brick.
 Maminydjama Magnolia Maymuru is an Indigenous Australian model.

Magnolia

Nymanina

Orchidea

A quaint and quirky flower name, until recently considered a bit too prim for most American classrooms but brought back to life in recent years by the attractive character of Primrose "Prim" Everdeen in the Hunger Games series. In the Top 300 girl names in England and Wales and on Nameberry, Primrose remains rare in the US, but is made more accessible by a raft of sweet nickname options, including Rosie and Posy.

 The flower name Primrose derives from Latin prima rosa, meaning "first rose", since primrose flowers are among the first to appear in early spring, heralding the coming of better weather. Primrose also has an alternative history as a Scottish surname deriving from the place name Penrhos, from the Welsh words pren "tree" and rhos "moor." The spelling was later altered due to association with the flower.

 In the H. E. Bates book and 90's British TV series, The Darling Buds of May, there is a character named Primrose Violet Anemone Iris Magnolia Narcissa Larkin, who has twin sisters named Zinnia and Petunia.

Primrose

Passiflora

Persica

Plumeria

This name of a showy, lemony plant makes an unusual entry into the name garden. 

Verbena

A frilly southern-accented flower name yet to be planted on many birth certificates. In the language of flowers, the wisteria is a symbol of devotion. It is named for American horticulturalist John Caspar Wister.

Wisteria

aubreykm's list "Not Your Grandma's Flower Names" of 32 great name ideas: Amaryllis - Wisteria!

Not Your Grandma's Flower Names

Yes, yes we know Rose, Lily, and Violet; but what else? A lot of these names are taken from the Latin or Greek scientific names, so the meanings can vary and be quite complex. If your Grandma *is* named one of these...Good for her!