BLOOM BY BLOOM

For Rebecca Letz, the choice of a florist for her backyard Berkeley wedding was easy: her younger sister, Joanna.

Joanna Letz, 34, is founder and chief visionary behind Bluma Farm in the Sunol AgPark, just 30 miles south of her native Berkeley. At Bluma’s 2-acre plot, she grows as many as 50 varieties of flowers ranging from the ordinary to the extraordinary.

“Joanna’s flowers were magical,” said Rebecca of her sister’s creations. “When you are moved by a wedding,

BLUMA FARM: http://blumaflowerfarm.com there are lots of reasons — the music, the couple, the setting — but the most common comment on our wedding was about the flowers; they were stunning.”

For the June celebration in their parents’ lush Berkeley yard, Joanna’s arrangements paired perfectly to Rebecca’s color scheme of bronze, peach and white. The chuppah dripped with silver and yellow, and the bridal crown and bouquet featured pops of burgundy with whimsical touches of wild greenery, including blackberry vines. Dozens of unusual shapes and varieties were incorporated, including craspedia, statice, dusty miller, poppy pods, nigella and alstroemeria. The overall result was personal and heartfelt.

On a recent day when the temperature hit triple digits in Sunol, Joanna traipsed through her rows of flowers in boots and jeans while the sun beat down overhead. As a farmer, every day her fingernails are rimmed brown with soil. She and her newly hired farm manager, Emily Leshner, have been working the field since 6 a.m. The night before, quitting time was 9 p.m.

Joanna’s passion for growing local and organic started 10 years ago after graduating from Bard College in upstate New York with dual degrees in history and human rights. At Bard, as part of her education, she’d traveled to five disparate countries — England, Tanzania, India, New Zealand and Mexico — to study the effects of globalization on small farmers.

That quest ignited her desire to attend the farm and garden program at the Center for Agroecology & Sustainable Food Systems at UC Santa Cruz, where she earned a certificate in ecological horticulture. She then apprenticed at several California farms, including Green Gulch, Heaven and Earth, and Slide Ranch in West Marin, where she was garden manager, before setting out on her own.

Joanna launched Bluma in 2014, and in addition to directly providing floral design services for weddings and events using her own yield, she now also supplies various florists and grocers, including Berkeley Bowl and San Francisco’s Bi-Rite and Rainbow Grocery. With up to 90 percent of flowers in the United States now being imported from around the world, Joanna is a fierce advocate for buying local and organic.

“Knowing where your flowers come from is the same as knowing where your food comes from,” she said.

On small farms, the margins are slight and the risks are great. “There is a worldwide movement in farming to ‘get big or get out,’ ” she said, noting that a mistake made in sowing, with water management or by a bug infestation can be disastrous. Last year, rats ate 25 percent of her starter plants before she was able to outsmart them with slippery table legs.

In addition to the brutal hours spent in the fields, running a farm includes operating a small business: Marketing, sales, delivery and outreach leaves Joanna little time for much else. A dance aficionado, she manages to slip in one class on Saturday mornings with a teacher she’s followed since attending Berkeley High.

“I credit my success to my willingness to work hard and ask questions,” she said as she showed off the new refrigerated truck and greenhouse with automatic irrigation full of seedlings. “If I am frustrated by something, I am probably doing it wrong and I need to ask how I can do it differently.”

Her family’s gardening roots go back generations. Both sets of grandparents raised chickens after emigrating from Eastern Europe. (Her mother’s parents survived WWII in hiding in Poland.) Joanna has strong childhood memories of working alongside her grandfather in his large vegetable garden, although neither of her grandparents sustained their lives through farming.

Committed to farming for the long haul, Joanna hopes to eventually work land closer to Berkeley both to shorten her commute and to bring her orbit even more local. Although she eschews the romantic notion of farm life, she admits that the payoff on her hard work still holds daily thrills.

“While making an arrangement, or when I’m packing the cooler full of my blooms, I still stare at every flower,” she said. “They are just so pretty.”

Louise Rafkin is an Oakland freelance writer. Email: style@sfchronicle.com.