Have you ever wanted to grow a winter vegetable garden, but haven’t been quite sure where to start? Or do you think that it’s too cold where you live to plant fall crops? Did you know that people as far north as Vermont can harvest winter vegetables deep into the winter under an unheated high tunnel? Today we are going to take a look at how to get started winter gardening.
As you might imagine winter gardening can be a boon to small homesteads committed to eating seasonally and producing their own food as it provides fresh vegetables during the winter. And anyone who has been exclusively eating canned and frozen vegetables for a length of time probably knows how delightful a reprieve a fresh salad is. Plus, harvesting more vegetables for a longer season means less time and space devoted to storage.
Unfortunately, winter gardening can be a bit more tricky to succeed at than summer gardening, and it might take some trial and error on your part to get the timing just right for everything. Don’t let that discourage you from trying some of the hardiest vegetables though. Even if you aren’t interested in going out to harvest vegetables in a January blizzard, this article and our season extension tips in our next post can help you to extend your harvest season in both the spring and the fall.
What are winter vegetables anyway?
Winter vegetables include most things that you plant in early spring. They are all the cold crops, and when acclimated many of them are surprisingly hardy. Cold crops include brassicas such as broccoli, cabbage, and kale, root crops like carrots, beets, and turnips, and many greens. We will be sharing a list of 10 of our favorite winter vegetables in a few weeks.
The first thing you need to do when planning a winter garden is to determine when your average first frost date is.
Your first and last frost dates can easily be determined from a quick internet search of your zipode and ‘first frost date’. The reason you need to know your first frost date is that you will need to count backwards from it to determine when to plant seeds. Once you have collected up your cold crop seeds to plant, you need to look at the seed packets to find the days to maturity. This is sometimes also listed as days to harvest.
You will need to count backwards from your first frost date the number of days the seed packet says to get an idea of when to plant. The idea is to get your crop to full size or almost full size before it gets too cold. Many cold weather vegetables won’t grow in extremely cold weather, but they will stay alive waiting to be harvested.
Now, the days to maturity is an estimate based on growing degree days not calendar days, and the planting date you select might need some adjustment to get just right. Because things grow slower as the weather cools, you may need to add a week or two to the number of days to maturity. It is a good idea to keep track of when you planted various seeds, so that next year you can reevaluate and adjust your planting date if needed.
Make sure to check your seed packets and make your plans for your winter garden early.
You might be surprised at how early in the summer you need to start planting seeds for your fall garden! For example, our average first frost date here in zone 8 Virginia is November 5th. We usually start our brassica seeds at the beginning of July. That way they are ready to harvest as the weather gets cooler, and we can harvest our frost tender cauliflower before the first frost. If/when I lived in Vermont, I would plant my Brussel sprouts and cabbages first thing in the spring for fall harvest.
One of the challenges you might run into with summer planting cool season crops is getting seeds to germinate.
Soil temperatures in mid summer are often higher than optimum for cool season crops. You may also have trouble keeping the soil evenly moist for germination under the hot summer sun. One of the ways you can help to get around that problem is to germinate seeds indoors and then transplant the sprouts out.
For vegetables such as root crops that are ideally not transplanted, you can shade the soil. This can be accomplished through the use of shade cloth, burlap, or agribon type insect barrier. We personally like to use agribon low tunnels for this purpose as pest pressure is often high on our fall planted crops and the row cover serves two purposes. We can water through the row cover, and it helps conserve soil moisture without reducing light to the seedlings which can be a problem with both shade cloth and burlap. If the seedlings are too shaded, they will be weak and easily damaged or killed by the sun when you remove their covering. It is also important when caring for your fall crops in the summer heat to keep them well watered to minimize their stress. Don’t be discouraged if they seem to be growing slowly. You will likely see their growth rate rapidly increase as the weather begins to cool.
If you live in zone 7 or colder, your winter vegetables will benefit from some sort of winter protection.
Zone 8 and above you can probably get away without it, but if you live in an area prone to a lot of wind or rain you may still wish to protect your plants.
There are 2 things in addition to low temperatures that can kill your winter vegetables. They are excess moisture which can cause them to rot and wind. A lot of times, it is not cold temperatures that damage or kill plants, but desiccation. Frozen soil is the equivalent of being in a drought because the plants cannot take up water, but their aerial parts can still lose water. Wind protection can make a huge difference to the longevity of your winter vegetables.
Low tunnels with a layer of plastic and or a frost blanket are the simplest, most inexpensive way to protect your vegetables. We will be discussing various season extension tips in our next post. For now though, a frost blanket will provide better temperature protection, but will not protect from wind or excess soil moisture like plastic does. Thus, we suggest gardeners in most climates utilize a combination of both to get the most benefits.
Once your vegetables are grown to mature size, they will hold in the garden and can be harvested as needed.
For leafy greens, be sure to harvest them when the temperatures are above freezing. For root crops you need to keep the soil from freezing around them to be able to harvest them. Placing a straw bale or big pile of leaves over them can help to keep the soil soft long into the fall.
At some point in colder climates your winter vegetables will probably get winter killed or damaged enough to no longer be palatable. Some of these cold damaged vegetables such as spinach are extremely hardy and will begin growing again as it starts to warm in the spring providing you with an extra early crop. We would like to note here that while it might seem counterintuitive, fluffy snow (not packed show though) is an excellent insulator. A layer of snow can actually help to protect your winter vegetables from the most extreme cold allowing them to survive and regrow in the spring.
So how hardy is cold hardy for winter vegetables?
It varies depending on the plant, and also on how well acclimated to the cold they are. It can also depend on how long the temperatures are low. An extended very cold period is more damaging than a brief dip. The below list of vegetables consistently survives through our mild winters. The temperatures here rarely if ever dip below 15 degrees, and we cover the garden with plastic if it is forecasted to be below 20 degrees or exceptionally windy. Some of these vegetables are much hardier than 15 degrees, some will eventually winter kill at these temperatures. However, even if they do end up dying mid winter they will still allow harvest deep into the fall in colder climates.
Beets, beet greens—the beets themselves are much hardier than the greens.
Carrots, turnips, mustard greens, Swiss chard, lettuce, spinach, parsnips, kale. Lettuce and spinach are more hardy than Swiss chard and many mustard greens.
Brassicas such as Brussel sprouts, collards, cabbage. Not all cabbage is equal. Seek out a cold hardy one such as a January King type. Broccoli plants will survive, however the florets will be cold damaged when temperatures start to get into the mid to low 20’s (or warmer if it is an early frost and they aren’t cold acclimated). If the plants survive undamaged, they will often go on to make new florets as the weather warms again. Please note that unlike most brassicas, cauliflower is NOT cold hardy. It will be damaged by freezing temperatures and should be harvested before your first frost.
We hope that this article encourages you to consider planting a winter garden. For those of you in colder climates interested in delving into winter gardening in more details, Cornell University has an excellent website devoted to the production of cold crops in high tunnels. In our next article we will discuss season extension tips to help you get the most out of your winter garden!
If you would like to make sure you don’t miss out on that article, please sign up for our newsletter.
Please remember
The information provided is for general informational purposes only. All information on the site is provided in good faith, for general informational and educational purposes only and is not a substitute for professional advice. We make no representation or warranty of any kind, express or implied, regarding the accuracy, adequacy, validity, reliability, availability, or completeness of any information on this Site. Accordingly, before taking any actions based upon such information, we encourage you to consult with the appropriate professionals. We do not provide any kind of professional advice. THE USE OR RELIANCE OF ANY INFORMATION CONTAINED ON THE SITE IS SOLELY AT YOUR OWN RISK. View full disclaimer here.
