Starting COLD HARDY VEGETABLES Super Early

lettuce_greenhouse germinating

So now that the Persephone period is almost over and the magic date of January 15th is upon us, what does that mean? It means our day lengths are getting longer and January 15th is when we start getting 10 hours of daylight that will continue to get longer every day. Have you noticed already it now gets dark around 5:30 instead of 5 pm? The darkest time of the year is over. What does that mean to gardeners? To learn how to start cold hardy vegetable seeds super early outside and how also how to start them inside read on.

STARTING COLD HARDY VEGETABLE SEEDS OUTSIDE: cold frme opened
If you want to try growing cold hardy vegetables outdoors at this time of year, you will need a cold frame, low tunnel or hoop house.

If you already planted cold hardy vegetables late last fall in a cold frame, low tunnel or hoop house, you may have noticed that the little seedlings haven’t been growing much at all as winter set in. Now with longer daylight hours, they will start to grow again and barring any devastating freezes, they will continue to grow and you can get cold hardy crops earlier this spring.

In late winter, before you have harvest your winter crops, decide what you want to plant in your bed once space opens up in your cold frame.  As the end of the Persephone period draws near (January 15) , you can re-seed the openings created from your harvesting or you could start planting seeds in your bed if you don’t have anything growing. My soil in my unheated greenhouse is at 40°F right now (as of January 12). Lots of cold hardy vegetables germinate in cold soil.  They will be slow to start at first but they will start as your soil warms up to 40°F and warmer. Now with the day light getting longer, you can think about starting early. The winter sowing you do will be ready for harvest by early spring, often long before the same crop when grown outside without protection. A bonus is many of the cold hardy winter crops don’t like our springs, bolting on the first few warm days so you’ll be able to harvest that spinach before it bolts!

Some cold-hardy plants planted inside a cold frame, low tunnel or hoop house can tolerate a hard freeze at night, provided they are allowed to thaw during the day. The plants must be completely thawed before you harvest them. In addition, put some winter row cover over seedlings at night to give them an additional 4-6°F protection even though they are already in a cold frame, etc. Remove the row cover on days when it is above freezing. Watering is necessary to get crops started, but they will generally need very little water during the winter season-early spring once established.

STARTING VEGETABLE SEEDS INSIDE:
I’ve already written about starting seeds inside on many earlier posts.
To learn all about starting seeds indoors to get a head start go here:
https://giantveggiegardener.com/2012/03/08/starting-seeds-inside/

WINTER HARDY VEGETABLES
The following list of winter vegetables to grow is from ‘The Winter Harvest Handbook’ by Elliot Coleman. These can be planted either as transplants (first started inside under lights) or outside as seeds in cold frames, low tunnels or hoop houses.

Asian greens-Tatsoi, Pak Choi (Mei Quing Choi), Mizuna, Tokyo Bekana,Komatsuna

arugula-Astro, Sylvetta

beets-Red Ace, Merlin, Touchstone Gold

beet leaves-Bull’s Blood, Red Ace

carrot-Napoli, Mokum, Nelson

chard-Fordhook Giant, Ruby Red, Argentata

claytonia

endive-Bianca Riccia

leek-Tadorna

lettuce-Red Saladbowl, Tango, Rex, Rouge d’hiver

 mache-Vit

minutina

mustard green-Toyoko Beau

radishes-Tinto, D’Avignon, Cherriette

scallion-White Spear

sorrel

spinach-Space

turnip-Hakurei

watercress

Early Spring Planting-Three Important Factors

Three important factors should be considered before planting seeds in early spring:

Amount of daylight hours-In the winter the sun is weaker in the northern hemisphere and we have less daylight hours. If you plant seeds too early either outside or in a greenhouse, the seedlings will be spindling when they germinate. Once we have 10 hours of daylight (we currently have over 10 hrs), we can start planting our cold hardy seeds. So in Santa Fe, we now have enough daylight hours. But wait, there are several more factors we need to consider before we plant seeds.

Soil temperature for germination for different vegetable seeds

Soil temperature for germination for different vegetable seeds

Soil temperature-If you are thinking of planting OUTSIDE, forget about it, your soil is probably frozen so of course you can’t plant anything! Even if it’s not frozen, it’s probably still too cold to plant outside. However it will warm up soon. How can you tell what temperature your soil is? You’ll need a soil thermometer. I prefer a compost thermometer that is about 18″ long so you can check both the soil and a compost pile. A soil thermometer is invaluable, as different veggies like to germinate at different soil temperatures. Insert it about the depth of the root zone of the plants, about 4”-6″ in the soil to see how warm it is. Notice the chart above gives an optimum range for each veggie.  If you have a cold frame, hoophouse or greenhouse your soil is probably much warmer already. So are you ready to plant? Not quite. There is one more factor to consider.

Air Temperature-The air temperature is also important and is the main thing people think of in considering when to plant seeds. It’s too cold at night to plant most veggie seeds outside or even in a greenhouse without extra protection BUT there are some wintergreens that are very cold hardy, some even hardy below 32°F at night. Even in an unheated cold frame or greenhouse, the temperature dips below freezing at nights so if you have a one, I suggest you put some row cover (winter weight-.9-1.0 mm.) over your beds. If you don’t have a greenhouse and will be planting outside in early spring, definitely put row cover over it at night but don’t forget to check your soil temperatures too.

I’ve compiled a list of these very cold hardy crops that can be started in a greenhouse now if the soil temperature and daylight hours are good. Many of these cold hardy crops can be planted outside as soon as the soil warms ups in March. For the list go to my blog at: http://giantveggiegardener.com.

Four Season Harvest

Four-season Harvest by Eliot Coleman

I am currently reading Four-Season Harvest by Eliot Coleman and am really enjoying it. It is about growing organically vegetables all year long. Great reading!  It has good information from season extensions to winter vegetable gardening and of course summer gardening. I highly recommend it. You can also go their site, fourseasonfarm for more information on all their gardening books and their farm.