Image source: QVC.

What: Shares of Liberty Interactive Corporation (QVCA), the parent of the home-shopping network QVC Group, tumbled today after warning of a weak retail environment in its second-quarter earnings report. As of 12:15 p.m. EDT, the stock was down 17.8%.

So what: Profits at the media conglomerate increased 13% to $127 million, or $0.27 per share, which beat estimates at $0.23. Revenue jumped 21% to $2.42 billion, boosted by last year's Zulily acquisition, meeting expectations.

Backing out the affect of Zulily's sales, revenue from QVC was up just 3%. Greg Maffei, CEO of Liberty Interactive, said, "QVC continues forward in a choppy retail environment," though he touted activity in Liberty Ventures Group, the investment side of the business, which made a gain of more than $300 million in its Liberty Broadband business.

QVC CEO Mike George noted that the business "experienced a deceleration in demand in the U.S. that has continued. As a result, our near-term perspective is more cautious."

Now what: Liberty Interactive did not provide specific guidance, but investors seemed unnerved by the cautious outlook at QVC, which comes amid murmurs of a broader pullback in retail spending. Nonetheless, George expressed optimism about QVC's longer-term position, saying it remains "well-positioned with our highly differentiated retail model, strong customer retention, and our ability to deliver compelling experiences across immersive commerce platforms." Given the growth at Zulily and Liberty's aim to diversify, I'd expect the stock to eventually rebound from today's dip.