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If you could only grow one crop, what would it be? Pole beans (or climbing beans) may be the most productive, keep-on-coming vegetable that any gardener can grow! See how to plant pole beans—with our seven steps to success.
What Are Pole Beans
Pole beans, also called runner beans, are a green bean in the legume family of plants, which works with bacteria in the soil to fix nitrogen at the roots. It’s a clever I’ll-help-you-if-you-help-me relationship, and it works to make beans a lot less reliant on us gardeners for extra nutrition.
Similar to regular bush beans which are low to the ground, pole beans grow in a vining manner and require some type of support. (Think “up a pole”!) They’re popular because they will keep on harvesting for about a month! And pole beans are all more disease-resistant than bush beans.
Common pole bean varieties include Kentucky Blue, Blue Lake Pole, Scarlet Runner, and heirloom Kentucky Wonder Pole.
Depending on the variety, pole beans grow from (at least) 6 feet tall up to 12 feet tall. But that doesn’t necessarily mean you need lots of garden space as you can always grow them UP vertically. You’ll need some type of support from a fence to a teepee to a trellis as we’ll explain below.
1. How to Support Pole Beans
Supports need to be at least 6-feet-tall from ground to the top. One popular support you’ve probably seen in gardens is the “teepee.” These work well because they stand up to the wind. Also, they’re quite attractive, made more glorious once the flowers appear and then the beans dangle down from overhead.
The beans find their own way onto these supports; they’re programmed to climb so the tendrils will cling on tightly and quickly begin to wrap themselves around any support they come into contact with.
Quick tip – once the beans reach the top of their supports, just take a moment to cut off, or ‘pinch out’ the growing points to stop them climbing any further. This both keeps things neater at the top, so it’s not a jumble up there, and it stops further growth that might distract these vines from flower and pod production.
Like all green beans, pole beans love one of the sunniest spots in your garden! Ideally, they’ll be getting at least five hours of direct sunshine a day, and preferably eight.
While pole beans enrich the soil with nitrogen, they still do need rich, fertile soil. Add a couple inches of organic matter such as compost to the soil a couple weeks before planting; this will also improve the water-holding capacity of the soil. Beans love a deliciously moist, fertile soil as they are thirsty plants. But you don’t want them sitting in pools of water, so good drainage is important, too.
If summers are particularly hot and dry where you garden, you might want to consider growing in “trenches.” You just dig out a trench and fill with compost before returning the soil. As this all decomposes it will create a rich, water-retentive cushion of goodness for roots to grow down into – and this will really help plants in hot weather.
3. Sowing Correctly
Sow green beans toward the end of spring. The soil temperature needs to be at least 45°F or 7°C, and preferably a bit warmer than that (55°F or 12°C). Green beans need warmth to germinate so it needs to be well after frost when it’s reliably warmer. If you sow too soon those seeds will languish and sulk or may even rot – and you run the risk of weak seedlings.
Beans grow best when direct-seeded outdoors. Don’t plant too early, as cold, moist soil will delay germination and could cause the seeds to rot.
Before sowing, it’s a good idea to get supports in place. Then, just pop in two seeds at each support, cover with an inch or 2 cm of soil, water well, then thin to leave the strongest of the two seedlings once they’re up.
In colder temperatures, it’s worth sowing under cover for more reliable germination. Sow into large plugs, or into small pots. Just fill them potting mix, dib a hole in the middle with your finger, pop in a seed and cover back over. Give them a good water then wait for a week or two for the chunky seedlings to push through. Easy!
They grow really fast – going from seed to planting in as little as three weeks – which is why it makes sense to sow towards the end of spring.
4. Water Well
Regular watering is a major factor in achieving a great crop of beans. Climbing beans produce masses of foliage and, of course, pods – and all of that requires lots of water. So long as you have relatively well-drained soil, it’s really very hard to overwater these thirsty plants.
In the summer, give your climbing beans a thorough, deep water at least once a week and when it’s really hot, step up the frequency to at least twice a week or more. Aim the water at the base of the vines and thoroughly soak the soil. Go off and continue watering elsewhere, then come back to the beans to soak them some more. Whereas most vegetables might have, say, a foot or so of foliage to keep hydrated, climbing beans have foliage way over head height to keep quenched, which is why such a thorough job of watering is so important.
If you don’t water enough, you may get dried out, wilted or browning foliage, that ultimately weakens the plant and makes it susceptible to disease. Check soil conditions regularly when it’s hot, dry, and windy – just pop a finger into the soil and check how damp it is. If it feels moist, you’re okay, if not – get on and water… quick!
You should have started your beans out with some healthy soil amended with organic matter. But if you do find the foliage going a bit anaemic and yellow, be prepared to jump in with a liquid tomato or vegetable feed to give your beans a boost of nutrients to help them along.
5. Boost Pollination
Bean flowers do a lot to draw in pollinating insects from far and wide, and they’ll even attract hummingbirds if you’re lucky enough to have those where you live. Nevertheless, you can supercharge pollination simply by including plenty of nectar-rich flowers among your vegetables and around your beans. Sweet alyssum, calendula, marigolds and nasturtiums are favorites; other pollinator winners are cosmos and zinnia. Just allow a few spaces throughout the veg garden for these blousy bloomers and watch pollination of all fruiting vegetables shoot up.
6. Dodge Pests
When it comes to beans, there are two pests to watch out for. Slugs may nibble at the young plants, which is another good reason to start them off in pots before planting, so they’re a bit bigger and more resilient. Keep an eye on your beans early on, pick off any slugs you find, and consider setting up slug traps to make a dent in populations early on.
The other major pest is black bean aphids or blackfly. These tend to congregate on fresh new growth, at the tips of shoots. Inspect foliage every few days and if you spot them, try blasting them off with a strong jet of water. If you have plenty of nectar-rich flowers among your vegetables you’ll find that, in time, natural predators like hoverflies and ladybugs or ladybirds will manage to bring things under control, without you having to resort to pesticides.
Finally, do just cut off any dead or diseased leaves that you do come across. This prevents problems from spreading, improves airflow around the vines, and keeps things looking nice and tidy.
7. Harvest Often. Yes, Often!
You know what’s coming next I’m sure! Pick your beans – and pick them often! Don’t wait!
If you pick the beans young and tender, the plant will be encouraged to produce more beans, because it hasn’t yet fulfilled its goal of maturing viable seed to grow the next generation. Leave the beans to get too big, long and lumpy and there’s a danger that the vines will slow down or even stop altogether.
So check plants regularly – every nook, cranny and underside – so you’re not missing any.
To see how it’s all done, watch Ben’s video which covers the above information and more!