Feb. 2 Column: Winter Sowing

What would you say if I told you it’s possible to plant specially-prepared containers with seeds and put them outside? Right when where it’s snowy and/or rainy for the rest of the winter? That sounds crazy, doesn’t it? But winter sowing is a viable, no-fuss way to start seeds. It just happens to be the topic of this week’s video and column.

Here’s a link to my column in today’s edition of The Spokesman-Review: Give seeds a cold start. (or you can read it lower in this post)

Before I continue, I wanted to clarify that this is my final, monthly winter column. You will be happy to hear that my weekly columns will resume on Sunday, Feb. 23.

Reasons to try winter sowing:

• You don’t need space to grow them indoors, under grow lights. I don’t know about you, but I never have enough room for all of the seeds I want to start!
• You don’t need special equipment.
• You don’t have to fuss over them for weeks at a time. Once the seedlings have filled the container(s) outdoors, it’s time to plant them in your garden.
• The plants won’t be exposed to (and killed by) the nasty fungal disease, “damping-off syndrome.”
• By the time you plant the seedlings in your garden, they will already be acclimated to your temperatures and sunlight. This eliminates the need for going through the week-long, tedious process of hardening them off.

Interested? Well, you’ll definitely want to read my column (again, the link to it is above). And you’ll want to watch this week’s video (see below), in which I take you through the steps for winter sowing. It’s easy and a fun way to feel like you’re gardening in the dead of winter!

Before I forget, the types of seeds you want to sow are those of annuals that are labeled “hardy annuals,” perennials that grow in your region, vegetables (primarily onion family crops and Brassicas such as cabbage, broccoli, kohlrabi and kale), and many different types of herbs. UPDATE 1/5/22: There used to be a website called wintersown.org that had an extensive list of seeds to start, but sadly, it doesn’t exist anymore. I will keep my eyes peeled for another helpful site. Unfortunately, I can’t remove the reference to that site in my video. Sorry about that. It’s one of those things that is completely out of my control.

Winter sowing garden column:

by Susan Mulvihill

Who enjoys doing fun DIY projects? And what if those projects involved gardening in the dead of winter?

Today’s topic is winter sowing and I’ll bet you will want to get started as soon as you’ve finished reading this. If you haven’t heard of winter sowing before, it seems like it’s all the rage these days. I’ve heard about it on podcasts, watched videos, and read social media posts extolling the virtues of this unusual technique.

How winter sowing works

The concept involves starting seeds outside in the dead of winter so the seedlings will be in great shape by planting time in our gardens. Don’t worry, I haven’t forgotten we live in a cold climate and that actually working in our gardens is still several weeks away.

By sowing seeds outdoors in modified containers, the seeds will determine the right time to germinate, rather than relying on a gardener to plant them at the most ideal time. Thanks to good air circulation, there’s no risk of the seedlings being killed off by the fungal disease called damping-off. When it’s time to plant them in the garden, they will already have acclimated to our temperatures and sunlight. What’s more, this method does not require seed-starting space indoors under grow lights, special equipment or fussing over the seedlings for weeks.

Winter sowing supplies

Start by collecting plastic half-gallon or one-gallon milk jugs, large pop bottles, or takeout containers with a deep bottom and lid (think roast chicken from the grocery store). Other supplies are seeds, potting soil, duct tape or masking tape, and a waterproof marker.

Sterile potting soil works best; avoid choosing mixes that contain fertilizer or water-retaining polymers. Do not use garden soil because it is too heavy for seed germination and might contain pathogens.

For tools, you’ll need a box-cutter, heavy-duty pair of scissors or a small knife for punching holes in the containers.

Winter sowing steps

1. Start with clean containers. Punch holes in the top of the container to allow your planting to get much-needed moisture in the form of rain or snow, and make drainage holes in the bottom. Remove the screw-on lid.
2. If using a milk jug or pop bottle, cut it in half crosswise so the lower half is 4 to 5 inches deep; leave about 2 inches of the top portion connected to the bottom. The purpose of removing most of the upper portion is to make it easier to fill the lower half with potting soil and plant seeds.
3. Pre-moisten the potting soil and place 3 to 4 inches of it into the lower half of the container; press down slightly to compact it.
4. Sprinkle seeds on the top of the soil. It isn’t necessary to cover tiny seeds, but press larger seeds such as peas or sunflowers into the soil and/or cover them with additional soil according to the packet directions. Lightly water in the seeds.
5. Replace the upper half of the container and use tape to attach it to the lower half.
6. Use a waterproof marker to note which seeds you planted and the date.
7. Place the container outside where it will get sunlight, rain and snow. Do not locate it under the eaves of your house or beneath other structures because the seeds and seedlings must get moisture and light. Make sure the containers won’t get blown over.
8. Here’s the easy part: the container won’t need any attention until temperatures begin to warm up. When the majority of the seeds have germinated, cut a little window in the upper portion of the container to increase air circulation. Be sure to keep an eye on the soil moisture from now on.
9. Once the seedlings fill the container, it’s time to transplant them into the garden. Since they have been outside all this time, they won’t require hardening-off, which is the time-consuming process of slowly exposing them to sunlight and temperatures prior to planting.

Seeds that are ideal for winter sowing

Annuals: Calendula, Canterbury bells, celosia, cosmos, marigold, morning glory, nicotiana, petunia, poppy, snapdragon, strawflower, sunflower.

Perennials: Baptisia, black-eyed Susan, butterfly weed, coneflower, blanketflower, liatris, obedient plant, sedum.

Vegetables: Allium family (leek, onion, shallot), arugula, broccoli, Brussels sprouts, cabbage, cauliflower, collard greens, endive, kale, kohlrabi, lettuce, pak choi, pea, radicchio, radish, spinach, Swiss chard.

Herbs: Chives, cilantro, dill, lavender, oregano, mint, parsley, sage, summer savory.