My 8×10 Backyard Greenhouse: Tour, Building Details, and FAQs

The greenhouse gets more questions than anything else I share. “How big is it”, “who built it”, “do we heat it”, “was it worth it”. So this post is a long answer, all in one place.

I call the greenhouse my office. The commute is a few steps across the garden, and the view from the potting bench is of Puget Sound. After all these years, I still have to remind myself it’s real.

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The Inspiration Behind It All

It started in a bookstore in La Conner, Washington. My husband and I were on a boat trip and stopped in to find something to read for the rest of the cruise. I walked out with Erin Benzakein’s Floret Farm’s Cut Flower Garden.

I bought it for the pictures. I’ll admit that. But somewhere between the dahlia chapter and home, I had decided I was growing a cut flower garden. The greenhouse came next, because if you’re going to start hundreds of seeds in the Pacific Northwest, you need somewhere warmer than a kitchen windowsill.

Building the Greenhouse

When we bought our house, this corner of the yard was bare. It’s hard to picture now.

We didn’t use design plans. I collected inspiration photos on Pinterest, handed them to our contractor, and he built our greenhouse based on them. The two of us figured out details as we went.

He built it during the winter months, which in the Pacific Northwest means cold and rain.

So most of the structure went together inside our oversized outbuilding.

Then he disassembled the whole thing, carried the pieces to the spot, and put it back together again.

I was able to do some of the painting while it was still indoors. I only wish I’d taken pictures of it coming apart.

These pictures were taken before I even thought about starting a blog, so they are pretty awful, but you get the idea.

And here it is after all the painting and new plantings next to it.

Greenhouse Size and Structure Details

Why We Chose an 8×10 Greenhouse

The two questions I’m asked most: how big is it, and do I have plans to share? No plans, as you now know. And the greenhouse is 8 feet by 10 feet.

We landed on that size for two practical reasons. Staying small meant we didn’t have to go through the permitting process. And our yard didn’t have room for more without blocking the water view. I’d rather have a small greenhouse in the Sound than a big greenhouse and a wall.

Technically, it sits in our front garden, facing the Sound. Backyard, front yard, the greenhouse didn’t get a vote. It went where the land was flatter and where the view was.

Framing, Walls, and Skylights

The main structure is standard 2×4 construction. The walls and ceiling are 1×4 tongue-and-groove pine with a clear sealant for protection. Standard 2×3 skylights bring in plenty of light for the plants.

Cedar Shake Exterior

The exterior is cedar shakes, and the cut-out trim matches the trim of our 1920 cottage. We found the original template used for the house and scaled it down. It’s my favorite detail on the whole structure.

Dutch Doors

There’s a custom Dutch door at each end. The top halves open for airflow on warm days, and the bottom halves keep Jax and Ollie inside with me on wet ones. If you’re designing your own greenhouse, I can’t recommend these enough.

Heating and Cooling

Heating a greenhouse through the Pacific Northwest winter is a real task. We installed an electric heater in the ceiling, set to hold 45°F through the winter for the geraniums I overwinter inside.

In spring, when the sun heats things faster than the doors can vent, an attic fan pulls the hot air out of the peak.

Temperature control is also what lets me leave. We can take a weekend trip on Wildflower without me worrying about the plants cooking or freezing while I’m gone.

Water and Electricity

We ran water to a hose hookup inside the structure and electricity to outlets at both ends. The outlets run the heat mats for seed starting and the LED Bistro lights outside. If you’re planning a greenhouse, put both on the must-have list. Hauling water gets old fast, and you want those heat mats.

Slotted Shelving

The shelves were slotted so water drained straight through rather than pooling under the containers. A small detail that saves a lot of mess.

5 Favorite Things About Having a Greenhouse

1. Fresh Cut Flowers Whenever I Want

I didn’t buy grocery store flowers once last summer. There was always a vase on the table and always a bouquet ready when a friend or neighbor had a birthday. That alone has been worth it.

2. Protection for Tender Plants

From fall until the last danger of frost has passed, the greenhouse earns its keep. The geraniums come out of the window boxes and containers, go into their own pots, and overwinter inside at 45°F. I’m not rebuying geraniums every May, and that savings adds up.

3. An Extended Growing Season

I can start seeds weeks before the garden is ready for them and keep things going after the weather turns. In our Zone 8b climate, that head start is the difference between zinnias in June and zinnias in late July.

4. Protection from Pests

Seedlings inside the greenhouse are out of reach of the slugs, rabbits, and deer that patrol the rest of the garden. They get to establish themselves before they ever face the outside world.

5. Garden Therapy

I can step into the greenhouse any time, in any weather, at any hour. The rain on the skylights might be my favorite sound on the property. It’s where I go to think, and some days that’s its most important job.

Greenhouse Questions I’m Asked Most

How Big Is Your Greenhouse?

It’s 8 by 10 feet. Small enough that we didn’t need a permit where we live, and small enough not to block our view of Puget Sound. For seed-starting and overwintering, it’s plenty.

Do You Need a Permit to Build a Greenhouse?

It depends on where you live and the size of the structure. Many areas allow small outbuildings under a certain footprint without a permit, which is one reason we kept ours at 8’x10′. Check with your local building department before you build. It’s a quick call that can save you a big headache.

How Do You Heat a Greenhouse in Winter?

We use a ceiling-mounted electric heater on a thermostat, set to 45°F. That’s warm enough to keep geraniums and other tender plants alive through a Pacific Northwest winter without running up a painful power bill. Heat mats handle the seed trays that need more warmth.

Does a Greenhouse Need Water and Electricity?

‘Need’ is a strong word, but I wouldn’t build one without them. The interior hose hookup means I’m not hauling watering cans across the yard, and the outlets power the heater, heat mats, and lighting. If you’re building from scratch, run both lines while the trenches are already open.

Is a Backyard Greenhouse Worth It?

For me, yes, and not just for the flowers. It extends the season, saves me money on plants I’d otherwise rebuy every spring, and gives me a place to garden in January when the rest of the yard is mud. If you start seeds every year or overwinter tender plants, you’ll use it constantly.

My Favorite Greenhouse Captures By Season

These are the photos I find myself coming back to. The greenhouse has its own character in every season, and I never get tired of watching it change.

Summer

Fall

30 Easy Outdoor Fall Decorating Ideas to Try This Season

30 Easy Outdoor Fall Decorating Ideas to Try This Season

Fall Season Ideas to Decorate the Outside of Your Greenhouse

Create a Fun and Spooky Vibe in Your Garden This Halloween

Winter

Creating Christmas Magic When Decorating Your Greenhouse

Christmas Decorating Ideas for a Small Front Porch

Spring

What’s Growing in My Early Spring Blooming Garden

What’s Blooming in My Late-Spring Cottage Flower Garden

Final Thoughts

I hope this answers the questions you’ve been sending about the greenhouse and helps if you’re planning one of your own. Keep it small enough to skip the headaches, run the water and power, and put it where you’ll see it every day. If you have a question I’ve missed, leave it in the comments, and I’ll add it to the list above.