The reality star told readers of his weekly People blog that the gesture had been intended to thank Emily for opening up to him during their one-on-one vineyard date the previous week.
She had revealed her tragic past over dinner, explaining that her fiancé had died in a plane crash and she later discovered that she was pregnant with his daughter.
"I can only imagine what it took for her to tell me everything she did," he blogged. "I didn't have a single chance to talk to her after that because she didn't receive a date of any type the following week. I wanted to just say, 'Thank you for sharing such an intimate part of your life with me'."
However, the 38-year-old admitted that in hindsight the gesture might have been a "little unfair" to the other women who were left inside. Meghan had joked that there should only be one rose that night, while Chantal had become tearful.
Nevertheless, Brad insisted that he didn't regret the picnic, but admitted that he did wish he had arranged something special for the other two women who didn't get a date this week: Shawntel and Marissa.
Host Chris Harrison also addressed the impromptu picnic in his own blog for Entertainment Weekly, explaining the effect that it had on the other bachelorettes at this stage in the competition.
"Brad had heard the women complain that after a one-on-one date they didn’t feel special so he attempted to do better with Emily who didn’t get a date at all this week," he wrote. "This sent the girls into a tailspin second-guessing everything they thought they knew. Further proof of just how real and raw emotions are at this point."
He previously said that Emily's past had "torn up the house" when the bachelorettes found out. "We showed a little bit of the emotion when she told the girls but it actually spilled over for hours," he said. "For literally the rest of the day girls were crying; it really destroyed the house."
> Click here for our full recap of what happened in this week's episode