Eco-friendly couple Nicole Richie and Joel Madden have created a green haven for their unborn baby.

Joel and Nicole are building an environmentally-conscious nusery for their second baby in their new Los Angeles $2 million home.

“She fussed over every imaginable detail, right down to the type of cotton in the sheets and the linens to the type of paint used on the walls,” an informant close to the couple spilled to The National Enquirer this week.

“Every piece of furniture in the baby’s room is formaldehyde-free.”

The insider added: “She scoured stores and researched on the internet for weeks to find wood products that are made from reclaimed sustainable wood from the Brazilian rain forest.”

“Even the toys are an environmentalist’s dream. Nicole is a model mum and she’s determined to teach her kids to honor the earth.”

Joel and Nicole already have a 19-month-old daughter, Harlow Winter Kate. The new baby is due later this summer.