MADRAS — The inspiration for NW Green Panels started with Karen Sagner’s goal of growing food at home, said her husband and the company’s founder, Jeff Sagner.

“My wife wanted to start growing food to make baby food,” he said.

Unable to find the right greenhouse design online, he drew one up himself. It proved popular enough to provide a weekend enterprise; Sagner sold his first creations on Craigslist. After a surprising number of sales at a Portland home-and-garden show in February 2013, Sagner and his business partner, Zebulin Hannon, quit their day jobs and went all in building modular greenhouses.

“We went into that show hoping to sell four or five greenhouses,” Sagner said. “It was a dream come true. To my surprise and Zeb’s surprise, we ended up selling about 30 of them.”

Orders bloomed, Sagner said; the company had $160,000 in sales its second year and $800,000 last year. And that’s about as far as he wants to grow, Sagner said Monday. Scaling up means greater costs and a narrower margin, he said.

“To go to the next level is a big capital investment,” Sagner said. “I don’t see myself getting much bigger.”

That’s not stopping growing interest in NW Green Panels. Sunset, a San Francisco-based home, food, travel, lifestyle and garden magazine, this year chose NW Green Panels to install a greenhouse as the focal point of its Sunset gardens and outdoor test kitchen at Cornerstone Sonoma, a market in Sonoma County, California, said Johanna Silver, Sunset garden editor.

“As a garden editor, I see a lot of greenhouses.” Silver said Monday. “This is a level of quality and design features I’d never seen. We were just really impressed with his love of architecture and the materials he used.”

The Sunset greenhouse, which provides a functional workspace for starting plants and an ornamental garden room, as well, features a basic frame of incense cedar and a slanted roof reminiscent of architect Frank Lloyd Wright’s style. Incense cedar is more durable, although harder to find than the more commonly used Western red cedar, Sagner said.

The 8-by-16-foot Sunset greenhouse has glass-panel walls, a custom feature, and standard, twin-wall, translucent polycarbonate panels on the roof. NW Green Panels greenhouses also feature an automatic, ridgeline ceiling vent designed by Sagner. A cylinder made in the United Kingdom and filled with wax expands and contracts according to the inside temperature. As it expands, it opens the vent, allowing warm air to escape. As it contracts, the vent drops and closes.

“It makes us unique,” Sagner said.

NW Green Panels sells greenhouses mostly in the Pacific Northwest with sales in California and as far away as Texas. About 80 percent of the company’s sales are to residential customers. A handful of buyers wanted greenhouses to start marijuana plants, Sagner said.

The basic greenhouse is a 4-by-4-foot platform, but the modular style allows the buyer to expand as large as he or she wants. “The sky’s the limit on that,” Sagner said. Greenhouses typically start at $2,000 but can run 10 times as much, he said. One client has a 16-by-24-foot greenhouse with an 8-by-16-foot koi pond inside, Sagner said.

“We’ve done some pretty interesting builds,” he said. “I get a lot of people who say they really appreciate the craftsmanship.”

— Reporter: 541-617-7815, jditzler@bendbulletin.com

Q: Where do you see the business in three to five years?

A: Jeff Sagner: This year is a pull-back year. We did $800,000 (in sales) last year, and it spread us too thin.

Q: How do you explain your sales doubling in the past four years?

A: I think the quality of the product is a huge part of it. Also, the service — we don’t just sell it to you and let you figure it out. We sell it to you and then we come set it up for you and get it going.