Wintering Greens and Low Tunnels
Greens are surprisingly hardy plants that gardeners can learn to grow even in the cold winter months.  Generally, direct seeded crops survive the cold better than transplanted crops. Follow these steps to have greens throughout the fall, winter and for a harvest in early spring! Katie Miller of Scratch Farm suggests planting claytonia, spinach, ruby streaks mustard, collards, and lettuce all in mid september. Everything else can be picked in late fall when it is ready, but the spinach can be saved for the really cold dark days - it will survive better than the rest.   

General Tips

Greens love compost! Apply a layer of compost before planting. The dark color will capture the sun's heat and provide important nutrients, helping plants grow faster and hardier.

Thin anything that is seeded too thickly (at least 1" between each plant).  If seedlings are overcrowded they wont have the space to bulk up enough to survive the cold.

Seed in September. Once they get to 7" tall, cut the leaves about an inch above the crown of the plant, being careful not to cut off the crown. The leaves then grow back (slowly if it is cold and dark, and quickly if it is warm and sunny). Harvest in November and December, but don't expect much in January or February, unless you have full grown spinach, kale, tatsoi, collards, or mache that hasn't already been harvested.  Growth is very slow in these months, and many greens become too damaged to harvest, but don't worry!  They will regrow in the spring, they aren't dead, unless they really are dead. 

Harvest will begin again in late February, so keep an eye on your garden, especially if there have been a lot of sunny days

Building hoop houses/low tunnels is an easy, efficient way to keep greens around in the winter for an earlier harvest:

Sept: mid to late september seed most things, keep the bed watered to get seeds to germinate

Oct: its not too late! you can still seed spinach, claytonia, and mache for harvest in the spring 

Nov: cover garden bed with row cover/agricultural fabric

Dec: put up hoops and plastic

Jan: usually not much to do, you may need to check occasionally and make sure ice and water aren't piling up on top of the bed

Feb: late feb, if its been sunny, see if there's anything to pick, clear off any water if it is collecting

March: take the plastic off in mid to late March, keep up with the harvest and weed if necessary, don't harvest on sunny days, because the greens might wilt, side dress with some compost if you feel like it.

Slideshow (expand on bottom right corner button for best quality)Buildling Low tunnels


Some things that can go wrong:

Water collecting on top of the hoops:  Sides of the raised bed were higher than the level of the dirt, which meant that when it rained, the rain collected in the bed rather than running off the edge. Plants can survive anyway, just not as nice looking.

Plastic can blow off in a strong wind, make sure it is well anchored

In spring, open up the tunnel when there is a mild rain to water the plants. Take the cover off if night temperatures are above freezing, but if you forget, and your plants wilt when you take the cover off, don't worry, they will grow back!

The ground freezes more in a raised bed, plant in ground when possible, but it will still work in a raised bed.

Mice and rats might love it under the covers, if you notice rodent damage, pull whatever it seems they have been eating, I haven't ever had any rodent problems with greens, but they have gone after carrots and parsley.

Fungus can be a problem sometimes, if it is too warm and moist under the covers, try to let the bed air out a little, but fungus has never done much damage to anything I've grown.


Read on for part 2: best things to seed in the winter (notes from Katie Miller of Scratch Farm)

Over-wintering greens allows you to reap even more fresh veggies from the garden and giving you a jump start on food for next year. Keep plants trimmed and harvest through late fall - plants will survive in the winter and start growing again early spring!