Ok, better late than never, let’s see if I can jump on the winter sowing train in the latter half of winter, eight weeks before my last frost date.
I store my carrots in sand over the winter (this is relevant, I promise). I have two containers of them, and the other day I cleared the last carrots out of the first one, leaving me with a big clear tupperware containing a few inches of leftover sand. It occurred to me that I could use that container, with the sand, for winter sowing – and in fact the sand might be helpful.
The point of winter sowing is to set up mini greenhouses outside that will allow plants to germinate a little sooner than they would in the bare elements. This lets gardeners get a head start on the growing season without taking up indoor growing space and without the need to ‘harden off’ the plants before setting them outdoors (they’re already outdoors, they don’t need to harden up to being used to being outdoors). Any mostly clear plastic or glass will do to create the greenhouse, and recycled salad boxes, milk jugs and tupperwares are common.
Now, a greenhouse will warm up during the day from solar heat being trapped within the clear walls, but generally when the sun goes away the temperature within a greenhouse quickly returns to the surrounding temperature – unless it is insulated or unless it has a ‘heat sink’ inside it. A heat sink is anything that will absorb heat during the day, and slowly release it over night. Water or rocks are both examples of heat sinks. And so is sand.
So, when I removed the last of the carrots from my clear tupperware container of sand, my mind started wondering if I was now looking at a mini greenhouse pre-equipped with a heat sink, perfect for a slightly elevated winter sowing system.
A scientist would compare the tupperwares with and without the sand, but I’m not feeling like doing a head-to-head trial this year. We’re at ‘proof of concept’ only. I gathered 10 small potting containers (old solo cups, plant cells and a yogurt container – all with drainage holes) and filled them with well moistened potting mix. I tucked each container into the sand, so the bottom several inches have the sand wrapped around them like a blanket. I generously sprinkled seeds on the surface of each container of soil (one type of seeds per container), labelled them, watered them in, then put the lid on the tupperware and placed it outside in the snow.
If all goes well, as Spring arrives I should start to see little shoots – and on warm days I’ll vent the lid so the plants don’t cook, and hopefully I’ll have some starts to put in the ground eight weeks from now.
Meanwhile, my first seedlings are doing fairly well but I won’t be starting anything else until after March break. We’re going away, and while my husband has set up an impressive computerized watering system for my indoor plants, it doesn’t quite have the sophistication to handle neonatal tomatoes. With a seedling heat mat I’m pretty sure I can make up for lost time – and hopefully the winter sowing will also take some of the pressure off for the indoor starts! Fewer to start, more room to work with on the growing racks.
In other garden updates, we had a little false Spring blip this month when all the snow melted and the ground wasn’t even frozen – my chives started growing and my peach tree tree optimistically started budding. We’re back to freezing temperatures again, and while the chives will recover I’m worried that my peach may suffer some lasting damage. Evidence in my own yard of how climate change is going to, and already is, threatening food supply…
