Winter Greenhouses: Easy Vegetables to Grow

Winter greenhouse gardening can challenge even seasoned horticulturists. With tons of fruits and vegetables to choose from, deciding what to grow becomes a puzzle. Luckily, garden greenhouses can protect plants from the cold weather. This means you can grow things even when it’s freezing outside.

In this guide, we’ll show you how to make the most of your greenhouse during the coldest months of the year. Keep reading!

A glass greenhouse in the snow

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Winter Greenhouse Gardening

Winter greenhouse gardening means growing plants in a greenhouse during the colder months. The structure provides a warmer environment than outside, protecting plants from frost. It allows gardeners to continue growing crops that wouldn’t survive outside. To make it work, it’s essential to ensure the greenhouse garden gets enough sunlight. Also, proper care is key to maintaining the ideal temperature and growing conditions.

Various mini plant pots on a windowsill

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What should you expect?

In winter, plants don’t grow as quickly as they do in summer, and they might not look as healthy. Some plants might not grow much at all, especially in December and January. But don’t worry! As long as the plants stay alive, they’ll start growing again when it gets warmer. So, even though things slow down in the winter, your plants will bounce back when spring comes around.

Various herbs

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Vegetables to Grow in Winter Outdoor Greenhouse

1. Hardy herbs 

Transitioning your herbs into pots during winter ensures their survival and continued growth. Bringing them into the greenhouse provides a nurturing environment throughout the colder months. Consider planting these varieties ideal for winter cultivation:

  • Chervil
  • Chicory
  • Chives
  • Coriander
  • Fennel
  • Garlic bulbs
  • Lavender
  • Lemon Balm
  • Marjoram
  • Mint
  • Oregano
  • Greek Oregano
  • Parsley
  • Rocket
  • Rosemary
  • Sage
  • Sorrel
  • Thyme
  • Winter tarragon
  • Yarrow

These tough plants can survive the coldest months, giving you a good harvest in winter. Pick from these different types to have a successful winter garden.

Tip: Planting several pots of the same herb means you can harvest them one after another. This way, when you harvest one pot, you can let the others keep growing. You’ll always have herbs available for harvesting, giving you a continuous supply.

Various vegetables together

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2. Salads and vegetables

To grow a successful winter salad, start by planting seeds in trays or pots filled with compost. When the seeds begin to sprout, move them into larger containers or bags filled with soil. Try growing robust winter lettuces like a salad bowl. Might as well consider pak choi, mizuna, lamb’s lettuce, and spinach for a tasty variety.

Here are more winter salad and vegetable choices:

  • Beetroot
  • Cauliflower
  • Coriander
  • Garlic
  • Onions
  • Radishes
  • Silverbeet
  • Snow peas
  • Turnips
  • Warrigal greens

These hardy veggies grow well in the cold, giving you lots of food during the season. Try planting some to make your winter garden better and have fresh food throughout the time of year.

potatoes in the ground

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3. Potatoes

Potatoes are popular winter vegetables, ideal for cultivation in sacks or large pots. For optimal growth, fill containers with a mix of two-part garden soil and one-part compost. Potatoes planted in early winter will mature by March, ready for harvest. Alternatively, start them indoors and transfer them outside as the weather warms.

Keep your wood greenhouse warm to protect potatoes from frost. Use methods like adding extra insulation or using a small heater. This simple step safeguards your plants and harvest during cold spells.

Someone picking out a lettuce

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4. Lettuce

If you need an excuse to try having more salad at Christmas, winter lettuce is the perfect addition. Winter lettuces like Little Gem, rocket and Lamb’s Lettuce prefer cooler environments. This makes them perfect for growing in the cold winter months.

There are plenty of varieties of lettuce you can grow during the winter. All you have to do is find the best one for you and you’re ready to add your all-important leafy greens!

Pak choi leaves

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5. Spinach and Kale 

In winter, spinach and kale are good to grow together. For one, they can handle really cold temperatures, even below freezing. You can usually harvest them about 50 to 70 days after planting. If it’s going to get too warm soon, it’s better to pick the whole plant early. Doing so will prevent the leaves from becoming bitter once they start making seeds. Most importantly, you’ll have tasty greens for longer during the winter.

A single broccoli

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6. Cabbage and Broccoli 

Cabbage and broccoli thrive in a greenhouse kept at ideal temperatures: 7-13°C at night and 10-21°C during the day. With these conditions, they can flourish all winter long. To ensure a successful harvest, start planting them early, around mid-winter.

By doing so, they’ll be mature and ready to transplant outdoors when spring arrives. Monitoring temperature fluctuations and adequate care can ensure these greens will grow well. Prioritise regular watering and occasional fertilising, too.

So, get ready to enjoy the fruits (and veggies!) of your labour from winter through spring!

Multiple Brussels sprouts

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7. Brussel Sprouts 

Brussels sprouts are a common vegetable grown in greenhouses during winter. They take about three months to grow and are ready to harvest when they’re about 1-2 inch wide, usually around March. When cooking them, it’s best to pick ones that are the same size so they cook evenly. This makes them taste better and ensures they’re cooked just right. By picking the right-sized sprouts, you’ll have delicious Brussels sprouts to enjoy!


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8. Carrots

Carrots are a fantastic addition to your winter greenhouse garden. Planted in late autumn, they can be ready for harvest as soon as the ground begins to thaw. Keep an eye on them during winter; if the ground thaws once or twice before spring, they may be ready for picking.

Tip: Opt for cold-hardy varieties to ensure successful growth in cooler temperatures. These varieties are better equipped to withstand the winter chill.

Bean sprouts

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9. Beans

Beans are perfect because they’re both easy to grow and high-producing. Meaning you’ll get a vast supply of this vegetable through the winter months.

Winter field growing beans thrive best in well-drained soil and full sunlight. This plant is frost tolerant, meaning it can survive through frost. However, as the soil temperatures reach 9 – 12 degrees Celcius, you’re likely to find the plant will die.

There are plenty of other beans you can grow in winter as well, including:

  • Broad beans
  • Snow peas
  • Sugar snap peas

Cacti plants

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10. Cacti

For a striking addition to your winter greenhouse, consider a cactus. While it thrives in sunny and warm conditions, it can also endure cooler temperatures. Known for its resilience, it’s an excellent choice for beginner gardeners. With their unique shapes and vibrant blooms, they bring beauty and low-maintenance greenery. Before planting, familiarise yourself with cactus care to ensure successful growth. Consider the Golden Barrel Cactus, Christmas Cactus, or Easter Lily Cactus.

Greenhouse in autumn

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Keeping the Heat In Your Winter Greenhouse

Your greenhouse can be the perfect place to grow vegetables, herbs and other plants in winter. However, keeping the heat in is key, especially in an unheated greenhouse. There are various ways to help heat your greenhouse and keep your greenhouse air temperature above that of the cold temperatures outside. 

Passive Solar

Passive solar plastic bottles are an excellent cheap alternative to electricity in keeping your greenhouse warm throughout the colder months. All you have to do is to paint the plastic bottles black and fill them with water.

The black paint will help in absorbing heat during the day. While at night, the stored energy is released automatically, which will heat the greenhouse space. For best results, you should place them around your wooden greenhouse or aluminium one. Try putting them on the wall or shelves.


To create a warmer greenhouse environment for your plants try using fabric row covers. This will also help to reduce heat loss for your greenhouse in winter. This is especially crucial for seedlings, as they tend to be more fragile.

Placing straw bales around your greenhouse can help with keeping the heat in. Although it may not add extra warmth, it will definitely help to reduce heat loss. This is crucial for your vegetables’ survival.

Regular packing bubble wrap also makes for an excellent insulator. You can layer your potted plants or vegetables and seed trays around the inside of the greenhouse walls and frame. Or, wrap the individual pots to keep the roots warm enough.

A greenhouse in winter at night

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Winter Greenhouse Maintenance

Heating your greenhouse at night is as important as it is during the day, but it’s also important to keep track of the temperature inside. This way you’ll be able to tell if your insulation isn’t working or to tell if it’s getting too warm as we go into late spring and even into late summer when we get some warmer temperature. This is the same no matter the material of your greenhouse – be it a polycarbonate or metal greenhouse.

Ensure a thermostat is working correctly to maintain the minimum nighttime winter temperature. It’s also best to invest in a minimum/maximum thermometer to monitor the winter weather conditions. You also want to clean your greenhouse’s gutters and water tanks.

TIP: It’s also important to make sure you have proper ventilation so the air inside doesn’t become stale with a lack of air circulation.

Gardening in a Greenhouse Benefits

  • Ultimate weather protection: They provide your plants with a level of protection against harsh weather conditions.
  • Pest prevention: They can be exceedingly beneficial in protecting your plants against pests and predators – such as birds and insects – from eating or attacking your plants.
  • All-season gardening place: You will have a designated area for gardening.
  • Multiple purposes: Thanks to the warmer and more humid environment that it provides, you can grow fresh, organic vegetables, flowers, bulbs and houseplants, including exotic plants and much more!

Now that you know all this, you’re ready to start winter gardening and show off your skills. If you’re new, check out our greenhouse gardening tips to get started!

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You should start planting the seeds around 6 to 8 weeks before your average last frost date. Some even need planting as early as 10 weeks prior. You need to know your first average frost date to be able to work out when your last average frost date is. Then you can start planting. Growing in an unheated greenhouse can be simple!

Besides the above insulation options, having a polycarbonate greenhouse can be another great cheap alternative to heating your garden building. There are plenty of advantages of polycarbonate greenhouses!

Yes. Your greenhouse is the perfect place to grow crops all year round. Take a look at the variety of warm-season plants you can grow!