Actor Reese Witherspoon on Monday sold her media company Hello Sunshine to a firm backed by Blackstone Group for $900 million. She called it the "right time" for the transaction, which will now allow the female-led company to get the attention and support it needs.

Witherspoon, 45, started Hello Sunshine in 2016, which was backed by AT&T and Emerson Collective. The new deal represents the support on her bet that Hollywood needs more stories told by and for women.

In an interview with CNBC’s Julia Boorstin on "Tech Check," Witherspoon explained how the newly formed venture will help growth and exposure.

“Now we’re going to have the ability to tell more stories, to hire more female filmmakers, to promote and lift up even more authors,” Witherspoon said. 

Blackstone Group is backing a venture by two former Disney executives, Kevin Mayer and Tom Staggs, who are trying to break into the media world on their own, much like Witherspoon. 

“Our platform will foster a uniquely creator-friendly culture that gives elite talent the resources they need to create and capitalize on their best, most inventive work. We look forward to backing Reese, Sarah, and their world-class team as they continue to produce and identify dynamic, engaging content for years to come,” Mayer and Staggs said in a release.

Hello Sunshine CEO Sarah Harden and Witherspoon will maintain their roles in the company. Their goal is to create content that is focused on female voices. 

“I’m really excited to extend our mission into animation so that we can reach more young women with this idea that women can be the heroes of their own story and do that authentically with real female creators,” Witherspoon said.

Some shows currently produced by the company include HBO’s “Big Little Lies,” Hulu’s “Little Fires Everywhere” and Apple’s “The Morning Show.”

Streaming services allow for media companies to produce a wider selection of different “series” that can be good for different audiences. Witherspoon said she enjoys being able to interact with viewers on social media as well to get a direct reaction on how they feel about the content. 

“We didn’t have these kinds of opportunities seven years ago,” she said. 

“I was making movies in a vacuum. I never really knew who was seeing them, what their feelings were. Now, I have this really great one-on-one relationship with people all over social media. ... We can really figure out and tease out exactly what audiences want to see.”