how to plant, grow & care for runner beans
complete growing guide
Traditionally grown in long rows on the allotment, runner beans work just as well on a teepee or up strings against a wall. We even sell a dwarf variety that you can grow in containers. As with all peas and beans, the more you pick, the more you get. So once you start picking the beans in June, you can’t stop until the first frosts kill off the plants. Even if the pods themselves start to turn tough, you can dry the beans inside and use them in soups and stews, the flowers look great in a vase and taste delicious in a salad.
We sell a range of runner bean seeds as well as runner bean seedlings which are available in April to plant out in May.
- Common name Runner Bean
- Latin name Phaseolus coccineus
- Type Half-hardy annual vegetable
- Height 2m (6 – 7ft)
- TLC rating Easy
- Aspect Full Sun
- Spacing 30cm
- Yield At least 0.5kg per plant
- Suitable for pots Dwarf varieties only
- Grow in a greenhouse? Yes, but not crucial
how to grow runner beans
where to grow runner beans
Soil type: Runner beans prefer to be planted in fertile moist ground.
Aspect & Position: Plant your runner beans in full sun but make sure they are sheltered from strong winds.
when to plant runner beans
Sow runner bean seeds from April onwards under cover. You can also sow direct into the garden in May-July once the soil has warmed up. Runner bean seedlings should not be planted out until the frosts are over.
how to plant runner beans
sowing runner bean seeds
Sow runner bean seeds from April onwards under cover. You can also sow direct into the garden in May-July once the soil has warmed up. If you are sowing the seed direct, then it is best to put two seeds in, as you will have a replacement if one fails to germinate.
Runner bean seeds are best planted in individual pots, root trainers or even loo roll tubes, as this way you can avoid root disturbance which all bean plants hate. After a week or so in a warm place the seeds will germinate. Once this happens they will need plenty of light, so as not to get too leggy. Once the plants are at least 10cm tall with two proper leaves you can plant them out, as long as there is no longer any risk of cold winds or frost.
Be patient and wait until April at the earliest to plant your seeds, as they cannot be planted outside until the frosts are over, and you do not want to let them stay too long in their pots, as they will start to tangle with their neighbours.
planting out runner bean seedlings
If you have bought seedlings they will need hardening off and should not be planted out until the frosts are over. To do this, simply pot the seedlings on into a 9cm pot, leave them outside during the day in a bright sunny spot then cover them with horticultural fleece or bring them in at night. Do this for a fortnight or so until the frosts in your area have finished.
Beans prefer to grow in moist, fertile soil, in a sunny, sheltered spot. Prepare the soil for planting by forking over and adding plenty of organic material. This will help to improve the soil's moisture retaining ability and fertility.
Historically, gardeners made a trench and filled it with well-rotted manure or compost before planting out. If you are really organised, you can dig a one metre wide and 30cm deep trench in the autumn and half fill with vegetable waste and even shredded newspaper as the winter progresses. Cover it up with soil in early spring, so that it will be well rotted by the time you plant the beans out in early summer. This will all help with both fertility and moisture retention, both much needed by your hungry runner bean plants.
growing runner beans in pots
If you have chosen a dwarf variety of runner bean, such as ‘Hestia’, you can grow them in a large container (at least 45cm diameter) or a deep window box as they will only grow to around half a metre tall. They will need really rich compost, or some extra organic matter such as horse manure, added to the bottom of the container.
how to care for runner beans
Water your runner bean seedlings well to get them off to a flying start. Runner beans are thirsty plants and do like plenty of moisture, so for a good succulent crop you will need to water regularly, especially during dry weather or if growing in a container. A weekly long drink at the root will benefit them hugely if the weather has been dry (more frequently if growing in containers).
Try to give your runner beans about half a watering can per plant when they are mature. You can lessen this if you have a rich soil full of organic matter which will retain the water. Make sure to avoid getting the leaves wet when watering your runner beans, as this can cause rust.
supports & frames
Standard climbing runner beans will need a good strong structure to grow up. It is best to have this organised before you plant them out as they will be searching for something to climb up straight away.
If you have the space (and the appetite for an awful lot of beans), the traditional long wigwam of bamboo canes crossed over at the top and joined together with a horizontal cane tied in along the junction point is a tried and tested method.
A more decorative version is the hazel arch over which the beans will scramble, allowing you to walk through the tunnel and pick the beans as they dangle down over your head.
For a more manageable crop, a teepee is all you need, with up to a dozen canes or bean poles placed in the ground at 30cm intervals in a circle and tied together at the top.
Alternatively, if you have a handy west facing wall, you can tie strings to it at around 2m high, dropping down to a tent peg in the ground, and you will soon have a beautiful floriferous wall, with an excellent bean crop thrown in.
Whatever structure you choose, plant a single bean plant at the base of each pole and tie it in to give it the idea that it should be climbing up. Once they have the idea of climbing, they should not need any more tying in, but do check, particularly if the weather is windy.
Harvest little and often, the more beans you pick, the more you get. Small runner beans, around 10cm long, are super tender and can be steamed and eaten whole, but usually you would wait until they are around 15 – 20cm long. The beans should snap neatly off the plant at the stem, pick them by hand or with scissors if you prefer. Runner bean flowers are edible and make a wonderful addition to a salad.
Don’t let your beans get so big that you can see the shape of the bean in the pod, they will be very tough. At this point, usually at the end of the season, pod the beans and dry them for winter use.
At the end of the summer, cut down the old stems and compost them. Leave the roots in the ground as they can have useful nitrogen nodules which will fertilise the ground for future crops.
If your structure is still looking like it will survive another season, it can be used again, but preferably for another crop such as climbing squash or sweet peas, so as to avoid any build up of pests and diseases. Otherwise collect in your canes and store somewhere dry so that you can start again in a new part of the garden.
- April: Sow seed indoors.
- May: Sow seed outdoors and plant out young plants.
- Water plants well during dry spells.
- Harvest regularly.
- Collect large beans to dry out for winter use.
- Cut down the old stems and compost them.
- Decide which varieties of runner bean you are going to grow in spring.
pests, diseases & common issues
slugs & snails
Runner beans are pretty problem free once they are well established. However, the young plants are a magnet for slugs and snails, so you really need to be on your guard. Starting them off indoors helps, as hopefully your windowsill or porch is pretty pest free, but once they are out in the garden, they are fair game.
If snails are a problem, get ahead of the game and do a thorough check under nearby pots and in cosy corners, it’s amazing how many hibernating snails you can find in the winter. Slugs are harder to find until they emerge with the warmer weather, so try some of our slug deterrents, and if all else fails a night-time slug hunt with secateurs in hand usually does the trick.
blackfly on runner beans
Black bean aphids or blackfly attack the tender shoots of many bean crops in the garden. The best approach is vigilance – keep checking the new growth for infestation of these tiny black bugs and squash them mercilessly. There is a theory that squashed aphids emit a pheromone that deter more adults from laying their eggs in the area. It certainly seems to attract their natural predators (ladybirds and lacewings) to finish off the job on your behalf.
Resist the use of pesticides, as if you allow the natural balance of predator and prey to emerge, your problem can be solved, and you therefore avoid killing off pollinators and other beneficial insects. If the infestation gets really bad SB invigorator is one of the safer pesticides to use as the fatty acids that coat and kill the aphids are less likely to affect the ladybird larvae.
runner bean rust
Runner bean rust is a fungal infection that appears in the shape of dark brown pustules on the underside of the leaves. It is prevalent in warm moist conditions, so try to avoid wetting the leaves when watering. Remove and destroy any affected leaves.
what is eating my runner bean leaves?
Most likely slugs or snails (see above).
why are my runner beans leaves turning yellow?
This could well be something called ‘Halo Blight’ which causes yellowing between the veins. It is caused by a bacterium and the best way to avoid is to keep well away from the leaves when watering your bean plants. Pick off any affected leaves and destroy, then destroy the affected plants and seed at the end of the season.
why are my runner bean flowers falling off?
The flowers will be falling off because they have not been setting (i.e. pollinated). See below for reasons why your runner beans aren’t setting.
why are my runner beans not setting?
There could be several reasons why you have flowers but no bean pods, particularly early on in the season. If it is still too windy and cold this can deter pollinating insects, so make sure you plant late enough and in a sheltered spot. There are some canny bumble bees that are frustrated by not being able to squeeze into the flower, so they ‘rob’ the plant by piercing the back of the flower to reach the nectar. Given that most years the beans are so plentiful you will be handing them to all your neighbours, you can afford to lose a few to the ingenious bees.
Later on in the summer if the weather is too hot and dry the flowers can drop off before they manage to set. Ensure you have plenty of organic matter in the soil to retain moisture, and water well at the roots in dry weather. It might also be worth testing the pH of your soil, as beans do not like it too acid (6.5 is about right).
why are my runner beans not germinating?
This is likely to be because the ground is still too cold. If they fail to germinate with a bit of indoor warmth, then the seed might have suffered from damp and begun to deteriorate. Always store your seeds in a dry box or tin in cool conditions.
frequently asked questions
what are runner beans?
Runner beans are usually a climbing vine with brightly coloured flowers that turn into long dangling flat pods with a slightly furry skin and bright pink beans inside. The whole pod is cooked and eaten, and the individual mature beans can be dried and stored for winter use. They originate from the tropics where they are perennial, but we grow them as half hardy annuals, so they need to be grown in the summer.
what spacing do I need for runner bean plants?
They will become big lushly leaved plants, so need at least 30cm between each plant.
when to pick runner beans?
As often as you can – the more you pick, the more you get! The size of the bean is largely a matter of personal choice. Something in between 15-30cm allows you the satisfying task of stringing the sides (if needed) and cutting them in neat diagonal chunks revealing strips of the bright pink beans within the pod.
how to pick runner beans?
Most runner beans snap neatly off the plant at the stem. If you are picking a whole lot, and want to save your nails, then scissors can help.
how long do runner beans take to grow?
If you have waited until the weather is warm enough the beans should start to appear 14-16 weeks after sowing the seeds.
which way up to plant runner beans?
It really doesn’t matter, the beans will germinate even lying on a piece of wet blotting paper, the shoot then heads for the light and the root for the dark, whichever way up they are planted.
are runner beans poisonous?
The beans themselves contain minute amounts of a toxic chemical that is destroyed by cooking, so best not to eat large amounts raw. When it comes to pets, the same applies – if you have so many beans you want to feed them to the dog, cook them first – they are clever enough to know not to steal too many raw ones for themselves!
how to make a runner bean frame?
There are several different types of frames you can use to support your runner bean plants. Take a look at the ‘Supports & Frames’ section above for some ideas.
which way do runner beans twine?
Runner beans twine clockwise (when looked at from underneath). You’ll soon be able to see for yourself though, as if you try to tie them in anti-clockwise, they will soon untwine and start twining again the ‘right’ way.
how tall do runner beans grow?
The climbing varieties easily get to 2 metres, sometimes 3. The dwarf or “bush” varieties are around 45cm tall.
should runner beans be pinched out?
The climbing varieties should not be pinched out until they get to the top of the cane. If you pinch them out below that level, you will simply get two shoots and potentially more of a tangle on your structure.
will runner beans recover from frost?
No, usually the shoot will wither and die, leaving a sickly distorted plant, so it is best to simply pull them up and start again with fresh seed.