October 13, 2019

From Death Valley to the North Pole

Snow on the pop-up greenhouse in early March

Janine Pineo Photo | Snow on the pop-up greenhouse in early March

To read all the articles in the series, click here.

• By Janine Pineo •

It is impossible to regulate the temperature in the wee pop-up greenhouse.

I know this to be true.

Once we’d established the greenhouse’s presence on the little deck, it was lined with special foil bubble wrap and then special clear bubble wrap, bricks and fieldstone were placed on the floor to help hold the heat, gallon jugs filled with water for the same reason and bags of soil were brought in to add to the mass.

It soon became apparent that in spite of all that, the temperature swings were wild, to say the least.

On a sunny day, even if it was below freezing outside, the high could top 80 degrees. Then, as the sun fell below the house’s roof and cast the greenhouse in shadow, the temperature would plunge — and I mean plunge — to about 10 degrees higher than the air outside. That meant as long as it stayed above 22 degrees all winter long, the greenhouse would be above freezing.

That so didn’t happen.

Instead, I had to purchase a little heater, thinking it would help warm things up. It did. It also helped warm up the electric bill.

I put it on a timer, trying to regulate the temperature better during the darker hours. If it didn’t run consistently at its low level, then the swings continued.

Some of the plants I’d saved were still doing OK as December waned. I waited to plant anything for lettuce or spinach, thinking I probably needed a more-even temperature if I was going to sprout a seed.

But it turned into a constant battle to do something resembling anything normal for a temperature. Opening up the door or window and letting in the cold meant sacrificing the warm buildup inside. Leaving them closed meant everything inside was being treated to a run through Death Valley with a night ride to the North Pole.

It finally hit me in January that I probably wasn’t going to manage to grow much of anything over the winter.

And I didn’t.

That’s when I set my sights on spring. Maybe then I could grow something in the wee pop-up greenhouse.

Next time: Moving the pop-up greenhouse off the deck