Incredibly versatile and super delicious, runner beans can be a great veggie to add to your plate. Here’s how you can grow them in your greenhouse! 

We love green beans, and usually grow pole beans (also called runner beans) every year. I try to can up at least four dozen pint jars of beans every year to store in our Cold Room.

Because I want to be able to put up as many jars as possible, I look for plants that will give us the highest yields in a small growing space. Even though I look at different varieties of runner beans,  I usually end up planting Scarlet Runner pole beans. I’ll get a much higher yield growing these beans as opposed to bush beans.

How to Sow Runner Beans in a Greenhouse

They are the same bean, but the bush bean stays small and the pole beans, well, they climb poles! Since our temperatures can fluctuate so much from morning to night, we decided to not take any chances and plant the beans in our homemade Greenhouse. Beans do NOT like a frost.

Our Greenhouse has served us really well and we have been able to grow lots of common beans, tomatoes and peppers. 10 mm poly is recommended for covering Greenhouses, but we used regular  Builder’s Poly (6mm) that we had left over from building projects. 

We built our greenhouse right over the manure and compost piles, saving us a lot of time and ensuring great soil. Here’s how we built a simple DIY Greenhouse for under 200!

If you’re thinking of building your own greenhouse (and why not?) here’s a great book to get some ideas from. I bought it the year before we built ours and had the chance to read it over several times. There are a lot of great tips and hints in the book.

Can I Grow Green Beans in a Greenhouse?

Yes! You absolutely can grow green beans in a greenhouse or a hoop house. If you have a soil floor in the greenhouse, you can just plant beans seeds (or bean seedlings) right into the ground. 

If you have a small garden or a small greenhouse, I would recommend growing these climbing beans with some kind of cane or wigwam support structure as you get much larger harvests in a small space.

Is a Greenhouse Necessary to Grow Green Beans? 

No, not all. You don’t need a greenhouse to grow beans. 

People can grow beans outside here in Zone 3, but remember that beans are a heat loving plant and cannot take any frost. Whether you can grow them outside in your garden depends on your night time temperatures.

When I do grow beans in the vegetable garden, I grow bush beans. Then I cover the leaves with Remay cloth every evening and remove it every morning.

This can get to be quite a pain on the daily chore list and if I even forget ONE time to put the cover back on, I may pay the price. It depends on how cool it gets that same evening.

The beans may be fine in the morning or they could be frosted over – they can never come back from that. Mulch can also help protect them. You don’t want slugs or snails getting to your beans!

Tips & Tricks to Grow Runner Beans in a Greenhouse

One of the best parts is the fact that planting pole beans in the greenhouse minimizes the risk of frost damage and boosts up the harvest potential. It’s toasty warm in there all day long, and I make sure to water at least twice a day.

With it as hot as it is right now here, I’ve been watering three times a day. Usually when we have a larger garden planted we use a lot of water timers and soaker hoses, but I didn’t do that this year.

It is important to remember that runner beans need a lot of soil moisture, which is why, growing them in a greenhouse is actually perfect. 

The main garden is small enough this year to handle with one oscillating sprinkler. The Berry/Garlic Bed has another sprinkler set up, so this year, it’s just a matter of turning the tap on and off.

When to Plant Runner Beans in Greenhouse in Canada?

If you live on the coast in Canada, you’ll be able to plant bean seeds in the ground much earlier than we can. We are in Zone 3 and we need start our beans in the house as seedlings.

Beans like a warmer soil temperature – beans like 10 C which is about 50 F. And it takes a while for our soil to warm here in the spring. So we get a head start and plant bean seeds in the house under growing lights. It’s often most efficient to start indoors a few weeks before the last frost.

Later we transplant them into the garden (if they are bush beans) or into the greenhouse (if they are climbing beans). The beans plants are usually transplanted around mid-June or any time in the late spring to early summer.

Using Black Bottles for Heat in a Greenhouse

We use these bottles as heat collectors during the season. That’s why they are sitting inside the teepees; we fill them with water and spray paint them black. This will help them get nice and hot when the sun is shining and release that heat late in the evening when the temperatures go down.

During the Winter, those bottles are tied onto the tarp that we put over the greenhouse. The bottles weigh down the tarp, in case of winds.

We’ve been using this system ever since we first built the greenhouse. It’s an inexpensive way to get more heat to the plants and protect the greenhouse in winter.

How to Support Pole Beans – Bean Trellis

Before you go ahead and get started, remember to first find the right support to grow the beans and support their lanky frame. 

We used Alder branches to make the runner bean teepees. Easy to get and easy to hammer them into the ground. I like to plant 2 or 3 bean seeds around each of the teepee poles. As long as my teepee supports are thick, they can hold a lot of bean vines without any problems.

You can see I stapled a layer of Remay cloth all around the inside of the Greenhouse. It adds about 2 degrees and when the temperatures dip here, those 2 degrees can make the difference of having food or not. I’ll take what I can get.

How to Get Pole Beans to Grow Faster

• Runner beans need regular watering. Don’t let the soil dry out too much.
• Climbing beans like well drained soil so make sure your soil is not too heavy (like clay soil) to promote faster germination.
• Keep picking beans off the plant. If you let bean pods get too mature, it signals the plant to slow down production.

Now the scarlet runner beans have grown up past the top of the teepees, and the flowers are forming. Don’t those plants look healthy?

They will just keep growing and wrapping themselves around anything that can support them.

Should I pinch out runner beans?

One the plants are as tall as you like, pinch out the top of the plant. This will encourage more beans to start growing and the bean plant will start sending out more shoots.

Mid to late summer, we pinch out the top of every plant. This sends more energy into setting bean pods – plus, our evening temperatures are starting to dip down, so it’s time for the plant to stop growing bigger and start putting everything it has into growing the bean pods bigger.

What is the ideal soil temperature to grow green beans?

Beans love soil that is between 50 – 85F. Because of this, you need to be sure to have some way to cool your greenhouse when temperatures get too hot.

I spray the outside roof and walls of our greenhouse on the days when outside temperatures are above 85; this cools the inside temperature very quickly. 

That we have open vents at the tops of the greenhouse helps a lot, as does the open weave door. You can also get automatic greenhouse vents, so you don’t have to worry about overheating.

Since the greenhouse door is framed with wood and covered with chicken wire, it keeps the pests out I want to and it doesn’t make it too difficult for the bees to get in there. We have a roll up poly door that we can roll down each evening to keep the cool air out.

Think about growing runner beans under cover, especially if you live in an area where the nights are quite cool!

Scarlet Runner bean flowers are so pretty. They’re edible and they also tend to attract hummingbirds and bees. It shouldn’t be long till I am pressure canning beans, and hopefully I will be canning a LOT of them!

Here’s how to pressure can beans safely. After canning I store them in the cold room until we are ready for them.

More Gardening Articles

• Want a Greenhouse? See how we built our own Greenhouse for under $200!
• Want to see how I go grocery shopping without ever leaving my house? Come along with me on a weekly trip!
• All kinds of great gardening tips.

Published in July 2013; latest update August 2022