Persephone Days

It’s been a challenge learning how to grow vegetables in my hoophouse (an unheated greenhouse). Over the 4 years I’ve had it, I’ve learned how to grow a variety of vegetables through much of the winter.

The main thing I learned that helped me was understanding the effects of the persephone days. That is the period of time when there are less than 10 hours of daylight each day. Plant growth for most vegetables slows or stops when day lengths shorten to 10 hours.

In order to have vegetables in the winter, plants have to be started in August and planted sometime in September so that they’ve reached 75% of their mature size by November. Then once they’re large enough to harvest in mid-November they go into a state of suspended animation. They stay alive and you can harvest leaves off of each plant until they’re picked over. Then you need to wait for late-February or March for new growth to kick off.

Some vegetables will grow faster than others during the 2 month persephone period (from Nov.19-Dec. 23 for us). The ones that seem to regrow best during this time are mustard (pictured above), senposai, spinach and arugula. Kale and swiss chard don’t seem to grow at all during this time.

In another week I’m going to experiment with doing some winter planting to see how early in the spring I can get some new crops to market. I’m hoping to try lettuce mix, boc choi, salad turnips, baby red russian kale and arugula.