Once planning on a grand wedding for 200 guests, Grammy award-winning singer Kelly Clarkson and Brandon Blackstock instead say “I do” in an intimate ceremony on a farm in eastern Tennessee. This week’s issue of PEOPLE reports on all the details -- the dress, the rings, the flowers, and their baby plans.

Hosting a party for around 40 close friends and family on Oct. 12 – eight days before their surprise nuptials at the private Blackberry Farm, nestled on 4200 acres in the Great Smoky Mountains – the pair “had no wedding jitters at all,” says their friend, Beverly Hills jewelry designer Johnathon Arndt, who attended the “pre-celebration” at the couple’s Nashville home. The evening “was Kelly and Brandon opening their home to say, ‘Thank you for being a part of our lives,’” Arndt tells PEOPLE. “They wanted to keep [the rest] sacred and hush-hush.”

They got their wish. On Oct. 20, the “Miss Independent” singer became “officially Mrs. Blackstock” – as Clarkson, 31, proudly tweeted the next day – exchanging vows with her groom, 36, in a romantic and serene ceremony that showcased the singer’s down-to-earth charm. Among the handful of guests in attendance: Blackstock’s children (with ex-wife Melissa) Savannah, 12, and Seth, 6. “I love Kelly,” Melissa, 39, tells PEOPLE. “I’ve known her for years, and I couldn’t ask for a better stepmother for my children. My kids love her.”

So secretive was the not-so-big day that even some loved ones didn’t learn about the wedding until after the fact. “It’s news to me,” her brother Jason, 40, tells PEOPLE. “It’s awesome. They both live their lives in the spotlight, so more power to them.”

Initially, Clarkson had envisioned a far more elaborate affair. After Blackstock proposed last December with a yellow diamond ring designed by Arndt, the pair planned to tie the knot before 200 guests at their home. But by August they had scrapped those plans. “We were so overwhelmed by it – by all the decisions,” Clarkson told PEOPLE. Settling on the right gown was among the biggest challenges. “When she tried them on, it felt like she liked every single dress,” says her stylist Steph Ashmore. The one she ultimately chose showcases her “Jane Austen-meets-country-relaxed feel,” she adds. Friend and fellow American Idol contestant Jim Verraros, who helped design the bridal crystal headpiece, says, “She couldn’t have looked more like the epitome of grace and style.”

For a long time, Clarkson didn’t see “I do” in her future, telling PEOPLE in March that before Blackstock she couldn’t even bring herself to sing about happily-ever-after love: “I would have been, like, ‘It doesn’t exist.’” But Blackstock, a manager for country star Blake Shelton who is Reba McEntire’s stepson, changed her mind. “He is everything I ever wanted in a guy,” she said. Now on her honeymoon, the busy star – she’s due to perform in Las Vegas on Oct. 30 – already has her eye on her next big project: a baby.

“We want to have more children,” she told PEOPLE last month. “We’re just excited.” Those closest to her share her newlywed joy. “Kelly truly deserves this,” says Arndt. “She has waited so long to have this special person come to her.”

More details on Kelly Clarkson’s wedding is in the 11/04/13 issue of PEOPLE; on newsstands everywhere now.

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