Gardening Tips: Cold Weather Greens

Editor’s Note: This column first appeared on 15 March 2017. (But, like pretty much everything in Michelle Smith’s archive, it’s still relevant.)


What to do this week

This week we are going to start our cold weather greens, things that you can start in the house and get into the ground even before the snow is gone. You will be able to transplant them into the garden as soon as you can work the soil. You can always grow greens indoors earlier in the winter so you can have greens inside, but for fresh garden greens, now is the time to seed the Brassicas.

Chinese cabbage Forest & Kim Starr [CC BY 3.0 (], via Wikimedia Commons Cauliflower By Dinkum (Own work) [CC0], via Wikimedia Commons Broccoli fir0002 | [GFDL 1.2 (], via Wikimedia Commons kohlrabi By 4028mdk09 (Own work) [CC BY-SA 3.0 (], via Wikimedia Commons Brussels sprouts By ThorPorre (Own work) [CC BY 3.0 (], via Wikimedia Commons Mustard Greens By মৌচুমী (Own work) [CC BY-SA 3.0 (], via Wikimedia Commons" width="800" height="800" /> Clockwise from upper left: Cauliflower (Dinkum, Own work, <a href="" target="_blank">CC BY 1.0</a>), Chinese cabbage (Forest & Kim Starr,<a href="" target="_blank"> CC BY 3.0</a>), Mustard Greens (মৌচুমী, Own work, <a href="" target="_blank">CC BY-SA 3.0</a>), Kohlrabi (4028mdk09, Own work, <a href="" target="_blank">CC BY-SA 3.0</a>), Brussels Sprouts (ThorPorre, Own work, <a href="" target="_blank">CC BY 3.0</a>), Kale (Dirk Ingo Franke, Own work, <a href="</a>), all via Wikimedia Commons.

Clockwise from upper left: Cauliflower (Dinkum, Own work, CC BY 1.0), Chinese cabbage (Forest & Kim Starr, CC BY 3.0), Mustard Greens (মৌচুমী, Own work, CC BY-SA 3.0), Kohlrabi (4028mdk09, Own work, CC BY-SA 3.0), Brussels Sprouts (ThorPorre, Own work, CC BY 3.0), Kale (Dirk Ingo Franke, Own work, ), all via Wikimedia Commons.

Brassicas include kale, broccoli, cauliflower, Brussels sprouts, collard greens, kohlrabi, mustard greens and Chinese cabbages. They are very cold tolerant. They do like a bit of warmth to germinate, but once they germinate they can tolerate cold, even freezing temperatures. They won’t grow much if it is freezing cold, but they will not be bothered at all if you get a frost.

So you really want to start them now. As I mentioned, a little bit of warmth is good for germination, but you don’t need a heat mat or anything like that. Room temperature warm is fine.

Usually a plant breaks through the soil after germination with a first pair of leaves that are not true leaves. They are called cotyledons. Once they break through to the air the true leaves will start to appear. So, you want to start those greens soon, and as soon as you see the first true leaves they are ready to transplant or move to a more exciting (for them) location. You can tell what true leaves are because they look like the leaves you are expecting, whether it be kale or spinach or whatever you planted.

Spinach, which isn’t a Brassica, is also good to start now. It is a really good late-winter green. It won’t germinate above 15ºC, so cool is good even for the germination phase. Spinach is a good one to start indoors, or even in a cold frame if you are set up for that. This time of year there is usually enough sunlight coming into the cold frame for the greens to be happy.

Otherwise, start them in soil blocks on your windowsill. As soon as they are a couple of inches tall it is safe to move them to a greenhouse or out to your garden. I will be following the weather as the season progresses, and giving you local recommendations as we see how it unfolds this Spring.

If you don’t want to use soil blocks, or you want to maximize your growing space, you can even plant lots of seeds in a flat, and start to thin them by eating them! This is a great treat when you are hungry for something that isn’t cabbage, turnip or carrots.

Next week, it will be time to start to think about seeding lettuce, tomatoes and peppers. The first phase will be the thinking, and that means deciding what varieties you want to plant and what varieties you can plant with your conditions. By the following week, it will be time to seed these warmer-weather annuals, but you do have to make a plan first. So next week, we will be doing some thinking and planning, to be ready to go by the first week in April.

Watch for my upcoming Seedy Saturday event at the Farmers’ Co-op on Keltic Drive on Saturday, March 25th, 10 am-2 pm. I will be able to give you more detailed advice on tomato selection then. We will have an apple grafting expert, David Baldwin, on hand during that Seedy Saturday event, so mark it on your calendars now and I’ll see you then.

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Market gardener, farmer, workshop leader, seed-saver, political candidate and mother, Michelle Smith has spent over 30 years coping with the challenges of our bioregion and in the process has built a store of practical and technical knowledge. The Inverness resident has served on the board of Seeds of Diversity Canada and represented Alternative Producers with the Federation of Agriculture but can do nothing about her hair. She is pictured with a head of Club Wheat, a seed that shares her approach to hairdressing.