Greenhouse Gardening Tips

5 Crops that Thrive in a Winter Greenhouse

Written by Hannah Nicklas | Nov 20, 2025 11:39:26 PM

Quick Answer:

The five crops that thrive in a winter greenhouse are leafy greens, hardy herbs, root crops, cool season brassicas, and quick growing “fill in the gap” crops. When you focus on salads like spinach and lettuce, herbs such as parsley and chives, roots like carrots and beets, compact brassicas, and fast growers like radishes or baby mixes, your greenhouse can keep producing fresh food all winter instead of sitting empty.

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When the first real frost hits your garden, it can feel like the season is over. Hoses are rolled up, bed look bare, and you start thinking about next year. But inside a well built greenhouse, your story can be very different. Cool loving crops like spinach, parsley, and carrots can keep growing in the protected space, so you can keep harvesting instead of just waiting for spring.

This blog is your guide to five winter friendly crops that do especially well under cover, and a fer simple planning tips so your greenhouse can feed you for months, not just a week or two.

What are the benefits of growing food in a winter greenhouse?

Growing food in a winter greenhouse gives you fresh harvests at a time of year when most garden beds are bare. You protect crops from wind, snow, and freeze thaw cycles while still giving them the cool temperatures they prefer.

A winter greenhouse also helps you:

  • Stretch you harvest season by several months
  • Make better use of your investment in glazing, vents, and climate control
  • Experiment with crops in a more controlled environment

Instead of seeing your greenhouse as a three season structure, you being to use it as a true four season garden room.

Can you really harvest leafy greens in a winter greenhouse?

Yes! Leafy greens are the easiest winter greenhouse crop for most gardeners and often the most rewarding.

Why leafy greens thrive in a winter greenhouse

Many salad greens actually prefer cool conditions. Instead of bolting and turning bitter, they grow slowly and develop sweet, crisp leaves.

In cold weather, crops like spinach and kale often  become sweeter after a light frost. Your winter greenhouse keeps them sheltered from the worst of the weather while still giving them the chill they enjoy.

Best leafy greens for winter greenhouse growing

For reliable winter harvests, focus on greens that are known for cold tolerance and quick maturity:

  • Spinach varieties bred for overwintering
  • Kale, specially curly and Russian types
  • Loose leaf lettuce blends and mesclun mixes
  • Arugula and other spicy salad greens

These crops tolerate cool nights and, with the extra protection of your greenhouse plus an inner row cover, many will keep producing deep into winter.

How to plant leafy greens for winter

In most climates, you will sow your main winter greens in later summer through early fall. The goal is to have plants mostly grown before the darkest part of winter. After that, your greenhouse acts as a living pantry where plants holds and slowly regrow.

A simple approach:

  • Sow thickly if you plan to harvest baby leaves
  • Give more space if you want full sizes heads or large kale plants
  • Use raised beds, trough planters, or deep containers for good drainage

Tips for harvesting winter greenhouse greens

  • Harvest outer leaves and let the center keep growing for repeat cuttings
  • Keep a light row cover handy for extreme cold snaps
  • Water in the morning so leaves can dry before cooler night temperatures

With one well planned bed, you can enjoy fresh salads for months in a winter greenhouse.

Which herbs do well in a winter greenhouse?

A winter greenhouse is an excellent place to grow fresh herbs for cold weather cooking. You get better flavor and less waste than buying plastic packs at the grocery store.

Why herbs belong in your winter greenhouse

Many culinary herbs are naturally hardy and tolerate cool conditions. They may slow down in midwinter, but they survive and bounce back as light increases.

A small herb corner near the greenhouse door makes winter cooking easier. Instead of relying on dried herbs, you take scissors to the greenhouse and cut exactly what you need.

Best herbs for winter greenhouse growing

Start with herbs that earn their space in cool conditions:

  • Parsley, a workhorse herb that thrives in cool weather
  • Chives, one of the earliest greens to wake up in late winter
  • Thyme and oregano, woody herbs that prefer sharp drainage and cool roots
  • Cilantro, ideal for fall and early winter sowing in cool climates

Most of these herbs grow well in deep beds or roomy containers.

How to care for herbs in a winter greenhouse

  • Use high quality potting mix or amended garden soil with good drainage
  • Avoid very large pots that stay wet and cold around the roots
  • Trim herbs regularly to encourage bushy growth

Container herbs are easy to move if you notice a cold draft or want to tuck them into a sunnier spot.

Where to place herbs inside your greenhouse

More tender or container grown herbs often do best in slightly warmer microclimates.

Try placing them:

  • On a central bench away from drafty doors
  • Along an insulated wall
  • Above any in floor heating system you may have

Tougher herbs like thyme can handle slightly cooler spots closer to the glazing.

Are carrots, beets, and other root crops good for winter greenhouses?

Root crops are a smart addition to a winter greenhouse. They are not as fast as baby salad greens, but they store well in the soil and offer excellent flavor.

Why root crops thrive in a winter greenhouse

The edible part of root crops grows below the soil surface, where temperatures are more stable. Your greenhouse roof keeps off excess rain and snow, so the soil does not become waterlogged.

Cold temperatures also concentrate sugars in many root crops. Carrots harvested in midwinter are after noticeably sweeter than summer ones.

Best root crops for a winter greenhouse

Good candidates include:

  • Carrots
  • Beets
  • Radishes
  • Turnips

You can mix quick crops like radishes along the edge of deeper beds where slower carrots and beets are growing.

How to prepare beds for winter root crops

Root crops need depth and an easy path for their roots:

  • Build raised beds or deep trough planters
  • Use loose, stone free soil to a depth of at least 25cm/10in to 30cm/12in
  • Avoid adding fresh manure right before sowing to prevent formed roots

When to sow root crops for winter

Sow root crops in late summer and early fall so they have time to bulk up before midwinter. Once they reach harvest size, your winter greenhouse acts like a walk in root cellar.

You can leave roots in the ground and harvest as needed, protecting the bed surface with straw, leaves, or row cover during colder spells.

Which brassicas thrive in a winter greenhouse?

Brassicas are classic cool season crops, and many perform even better with the added protection of a winter greenhouse.

Why brassicas fit into a winter greenhouse plan

Crops like kale, bok choy, and tatsoi grow well in cool temperatures and tolerate light frosts. Inside your greenhouse, they are protected from harsh wind and heavy moisture while still enjoying the cold they need.

They also add variety to winter meals with different textures and flavors.

Best brassicas for winter greenhouse growing

Consider planting:

  • Asian greens such as tatsoi, mizuna, and bok choy
  • Compact cabbage or mini heading varieties
  • Cold hardy kale types

These crops can be grown in beds or large containers depending on your layout

How to space and manage brassicas in winter

  • Plant closer together for baby leaf harvests
  • Give more room for full-sized heads and larger plants
  • Stagger sowing dates in early fall to spread out your harvests

Pest pressure is usually lower in winter, but you should still check plants regularly for aphids and signs of mildew. Good airflow and prompt removal of damaged leaves are usually enough to stay ahead of issues.

What quick-win crops grow fastest in a winter greenhouse?

Quick-win crops help you use every corner of your winter greenhouse and give you fast results if you are still learning how your structure performs.

Why quick crops are helpful in winter

Fast growing crops:

  • Keep the greenhouse feeling productive
  • Fill gaps between slower crops
  • Let you test new areas and microclimates without a long commitment

They are ideal if you are new to winter greenhouse growing or working with a smaller space.

Best fast crops for winter greenhouse growing

Look for crops that mature in about 30 to 45 days:

  • Radishes in open spaces or along bed edges
  • Baby salad mixes between slower crops
  • Green onions in narrow rows or along pathways
  • Microgreens on shelves and benches in trays

You can tuck these into corners, under benches with added lights, or in shallow containers.

A simple sowing rhythm for winter quick crops

Try a small but steady routine:

  • Every two weeks, sow a tray of microgreens and a row or two of radishes
  • Once a month, refresh a strip of baby leaf mix between larger plants

This light schedule keeps a steady stream of quick harvests coming into your kitchen without overwhelming your time.

How do you plan your winter greenhouse layout so it feeds you for months?

The real power of a winter greenhouse comes from combining these crops in a layout that fits your space and climate.

Example layout for a medium winter greenhouse

In an 8 by 12 or 12 by 16 greenhouse, you might:

  • Use one main bed for salad greens and Asian greens
  • Dedicate another bed to root crops, with borders of green onions and radishes
  • Reserve a bench or raised trough for container herbs
  • Set up shelves or small table for microgreens and seed trays 

Place the toughest crops closer to the glazing and keep more tender plants and containers in the slightly warmer central zones.

Timing you winter greenhouse plantings

Think in terms of planting waves instead of one big fall planting:

  • Late summer: sow root crops and long season storage types
  • Early fall: plant your main salad beds and brassicas
  • Through fall and early winter: Keep seeding quick crops and microgreens on a simple schedule.

This staggered approach means you always have something growing and something ready to harvest.

Quick climate control checklist for winter

To keep your winter greenhouse performing well, review the basics:

  • Glazing: is it insulated enough for your climate and clean for maximum light?
  • Foundation and flooring: does it drain well and provide some thermal mass?
  • Ventilation: do you have working vents and a fan to move air?
  • Heat: do you have a safe, reliable heat source for the coldest night if your climate requires it?

Is a winter greenhouse worth it for your garden?

 

A winter greenhouse is worth it if you want fresh food outside the traditional growing season and are willing to grow crops that truly enjoy cool weather.

By focusing on:

  • Leafy Greens
  • Hardy Herbs
  • Root Crops
  • Brassicas
  • Fast Quick-Win Crops

you turn your greenhouse into a productive winter garden instead of storage space.

If you are dreaming about winter harvests and are not sure which greenhouse size, glazing, or climate control options make sense for you climate, our team is happy to help you talk through the options.

With a little planning and the right structure, your future winter salads, herbs garnishes, and sweet, crunchy carrots are already within reach. All you have to do is open the greenhouse door and start planting.