Well Worth The Effort
For years we have started our seedlings on the porch, with relative success. It provides the plants with adequate protection from frost until we can put those tender seedlings into warm and cozy garden beds come the end of May. Of course, we’d love to have a big old hoop house like the pros use, but it’s hard to justify the high cost to get one started and keep it running unless you make your living that way. We’re not there yet. This is still mostly a wonderful hobby of ours.
This year though, we built a mini greenhouse for the seedlings to live in and what a difference! We still sprout them on the porch, on heat mats, but then they went in the greenhouse. The plants get a lot more direct sunlight throughout the day, resulting in the rich green color and sturdy, stalky plants pictured above.
This little structure was very inexpensive to build. Yeah, It’s ugly, but it’s cheap and it gets the job done.
I didn’t save receipts, but I’d estimate we didn’t spend 100 dollars to build this. There’s no artificial heat source and no lights. So far, there’s been no need to heat it. All of the lumber came from scrap materials left over from other farm projects, which you could probably get from your local landfill’s demolition dumpster. It’s 10′ wide x 5′ deep x 7′ tall and covered with 6 mill plastic. The roof is made of transparent corrugated plastic paneling from the building center, probably the most expensive component, but important to help it last through many years of harsh New Hampshire winters. We put about 12 hours of work into it over a weekend.
The real benefits are that we can keep our plants in one place and they get a lot more direct sun. We don’t have to move them outside during the day to harden them off (get them used to sunlight and wind) and then in at night to protect from them from frost. The greenhouse warms up within minutes when the sun hits it in the morning, so the plants begin their growing day sooner. At night, we’ve had temps down below freezing, and it’s gotten down to 32F inside, but because the plants don’t experience the dew and the wind with the greenhouse closed up, the plants are not subject to frost, even at freezing temps.
We’re no using it for our heat loving plants – for peppers and tomatoes we would have to heat it at night. Given the size of the greenhouse, we could probably achieve temps of 80F easily with a single infrared heat lamp. I might just build a second one with double wall plastic to help insulate it, for use with heat-loving plants, but for now, this is working great for our brassicas, our flowers, our alliums, leafy greens, etc.