Grower's Guide: What to Grow in a Greenhouse All Year Long

One of the great things about having a greenhouse is that you can grow your own fresh produce almost all year long. These useful structures allow you to grow different types of plants and extend your growing season by many months.

Wondering what plants you can grow in your greenhouse each season? Take a look through this year-round greenhouse guide!

Seasonal Plants: Greenhouse Growing Guide

When deciding what to grow in a greenhouse during each season, you need to consider two important factors – the length of sun exposure and the outdoor temperature. If you’re using a high tunnel greenhouse, this is even more important since they don't have heaters. Instead, this type of greenhouse relies on insulation and solar energy to create a microclimate for your garden. A major advantage of these structures is that they will provide shelter from wind and inclement weather without overheating your plants.

While light and temperature are still important when using a standard greenhouse, the fact that they have heat and ventilation can help give you more climate control. This can also make it easier to grow tender plants and continue growing crops during the off-seasons.

No matter which option you choose, you'll be able to enjoy planting and harvesting crops almost all year long.

Spring Growing Season

Gardening in early spring is mostly about getting a head start on the planting season. You can use your greenhouse to start sowing seeds and starting off hardy plants like:

  • Lettuce
  • Peas
  • Cabbage
  • Leeks
  • Shallots
  • Brussels sprouts
  • Onions

Even if you’re planning to eventually move your vegetables outside, your greenhouse is the perfect place to give them a strong and healthy start.

Mid-Spring Planting

By mid-spring, you can start to sow fast-growing, tender plants inside your greenhouse. This includes:

  • French beans
  • Cucumbers
  • Melons
  • Pumpkins
  • Squash
  • Sweet corn

If you’re using a heated greenhouse, you can also start:

  • Peppers
  • Tomatoes
  • Basil
Growing in a greenhouse backyardGrowing in a greenhouse backyard

Summer Growing Season

From late spring to mid-summer, you’ll want to start thinking about moving some of your greenhouse plants outdoors to their permanent locations. This will help free up some space so you can have room to plant even more items inside.

Protecting Your Plants from Summer Heat

During the summer months, you’ll need to take some steps to protect your plants from heat and make sure to water strategically. You'll want to be extra careful with any plants you decide to keep inside your greenhouse. It’s important to maintain good ventilation and make sure the greenhouse doesn’t get overheated. Otherwise, it can damage your plants. You may want to keep some plants heat-loving plants like beans and squashes inside your greenhouse all summer long. Sometimes, this can help you achieve an even larger crop harvest.

Mid-Summer Harvest

By the middle of summer, you’ll be able to start enjoying some of the fruits of your labor. This is when you can begin harvesting crops and removing spent plants, like cucumbers, melons, and French beans.

Late-Summer Planting

In the late summer months, you’ll want to start thinking about adding new plants to your greenhouse. This is a great time to start growing baby carrots and lettuces indoors. If you have a heated greenhouse, you can also sow some new potato plants so they’ll be ready in time for your Christmas dinner.

Autumn Growing Season

Before you start your fall gardening, you’ll need to take some time to get rid of the spent summer crops. This is also a good time to plant certain crops that can mature indoors over the winter months. This includes:

  • French beans
  • Parsley
  • Peas
  • Broad beans
  • Hardy lettuces
  • Radishes
  • Green onions
  • Collards
  • Brussels sprouts
  • Kohlrabi

Winter Growing Season

While you might think your options are limited in the cold winter months, knowing what to grow in a greenhouse during this season can help expand your crop harvest.

After you’ve harvested your fall crops, you’ll want to take everything out of your greenhouse and give it a thorough cleaning. Check it to make sure there’s no damage you need to fix, then think about relocating it to a sunny location.

Once you’ve prepared your greenhouse for winter growing, you’ll be able to sow some hardy, frost-tolerant plants. Root vegetables are a common option, but you don’t have to stop there. You can also grow cold-hardy versions of celery, broccoli, or peas. Some other great crops for growing in a greenhouse during the wintertime include:

  • Beets
  • Carrots
  • Leeks
  • Radishes
  • Rutabagas
  • Parsnips
  • Brussels sprouts
  • Asparagus

You can also grow green leafy vegetables like:

  • Endive
  • Swiss chard
  • Kale
  • Radicchio
  • Arugula
  • Spinach
  • Cabbage
What to grow in a greenhouse largeWhat to grow in a greenhouse large

Benefits of Greenhouse Growing

Aside from the opportunity to grow crops year-round, there are also some other great reasons to use a greenhouse. Here’s a closer look at some of the most important.

Protection from Weather and Pests

Since all types of greenhouse provide shelter, they’ll protect your plants from damage that can be caused by hail, strong winds, and frost. The translucent cover also diffuses light to protect plants from over-exposure to the sun’s harsh rays.

In addition, greenhouses can help protect your crops from insects, animals, and other pests. This will help you avoid having to use toxic pesticides and prevent you from losing your precious crops to deer, birds, or moles.

Portability and Versatility

Many greenhouses are lightweight and portable, making them convenient to use and easy to move from one location to the next. This allows you to ensure you’re always getting the best sunlight exposure during each growing season. Some models are also customizable, allowing you to change the size and configuration depending on your current needs. This makes them a great option for everyone, from the novice gardener to professional growers.

Tips for Enjoying Better Planting Seasons

If you really want to enjoy a great harvest season after season, knowing what to plant in a greenhouse is only half the battle. There are some other important steps you’ll want to take to improve your output.

The good news is, once you’re master the most common greenhouse growing tips, it’s quite easy to find your green thumb. Here are eight of the most important things you need to know.

1. Choose a Sturdy Greenhouse

While you may not want to spend a fortune on a greenhouse right away, it’s also important to choose one that will stand up to the elements. Look for a greenhouse that is made of high-quality steel and has a waterproof cover. This will help ensure the one you choose will last you at least a few years.

2. Select Your Plants Wisely

It’s important to choose the right types of crops for the season. If you’re new to year-round greenhouse growing, you may also want to start out with hardy, easy-to-grow plants. This will allow you to figure things out as you go without having to worry about losing delicate crops.

3. Use the Right Soil

Good soil is one of the most important keys to growing healthy crops. Make sure you choose high-quality gardening soil and add compost or manure as recommended for the types of crops you plan to grow.

4. Let Your Greenhouse Breathe

Ventilation is another important element of successful greenhouse growing. When the weather is warm, make sure you open up the doors and windows to your greenhouse and let the fresh air in. You might also want to keep a fan running inside to help prevent the air from getting stagnant.

5. Choose a Sunny Location

Plants need warmth and sun to thrive. During the colder months, you may need to relocate your greenhouse to ensure it gets plenty of sunlight. While this may seem like a lot of effort, it’s not really that hard and will make a big difference.

6. Keep Your Greenhouse Organized

Organizing your greenhouse and keeping it tidy will help you optimize the space so you can fit even more plants inside. Keeping things neat also helps you avoid having a bunch of unused pots and equipment lying around. This is important since these items often become new homes for pesky slugs and snails.

7. Don’t Forget Seasonal Cleaning

It’s important to thoroughly clean your greenhouse at the end of each season. This will help eliminate potentially harmful bacteria, mold, and pests. Once you take everything out, it's also easier to inspect your greenhouse for problems and neatly organize your items as you put them back in.

8. Keep a Greenhouse Journal

Lastly, it’s a great idea to keep track of what you planted, the type of soil mixture you used, your watering and fertilization schedule, and what you were able to harvest. This will help you learn what works and what doesn’t so you can improve your results each season.

Enjoy the Benefits of Greenhouse Growing

Regardless of the type of gardening you choose to do, having a greenhouse can bring lots of benefits. Not only can it extend your growing season, but it can also significantly improve the size and quality of your harvests.

Whether you choose a fully heated and ventilated greenhouse or a simple high tunnel option, you’re likely to find that it’s an investment that pays off tenfold for years to come.