How to Grow Runner Beans

Botanical Name: Phaseolus coccineus

Plant Type: Tender Perennial

The runner bean, Phaseolus coccineus, is also known as the seven-year bean, because it is a perennial climbing plant, retreating to ground level each year to avoid frosts. Native to the mountains in Central America, it has been cultivated by the Native Americans there for more than 2000 years.

For gardeners in temperate to cool regions, it can be the best type of bean to grow in the garden, because it is most productive in areas with cool summers, such as coastal Victoria, Tasmania, and the tableland areas of New South Wales.

It is versatile in the kitchen, with the immature pods used as snap beans, or the pods can be left on the vines to mature for harvesting the large beans themselves. The flowers are very colourful and the runner bean can justify its place in the garden for its beauty alone.  

Varieties

There are, perhaps, three dozen varieties of runner beans in existence, with several varieties having been lost. Modern types differ from the wild form, because breeding has developed varieties with large pods and beans, as well as delaying the appearance of strings in the pods.

Most varieties are vigorous climbers, but a few dwarf varieties exist that do not require support. Other differences occur in flower, bean colour and productivity. Scarlet Runner, the traditional variety grown, produces bright red flowers and purple bean seeds with black speckles. Painted Lady is an old variety with bicoloured flowers of light pink-white and red, and brown beans decorated with cream flecks.

Cultivation

Gardeners contemplating growing runner beans need to understand from the outset that they do not enjoy hot summers, with high temperatures above 30°C. These temperatures cause the flowers to fall off without setting which results in no flowers or beans.

In hotter regions, north of the Great Dividing Range in Victoria, runner beans should be established in partial shade and are basically most productive in autumn, provided early frosts do not set them back. In cooler coastal and more southerly regions, plant in full sun in the best site in the garden and they will happily produce pods throughout summer.

Always plant with support as these are vigorous beans once established and can make a dramatic feature in the garden.

Sun: Full Sun or Part Shade        

Pollination: Bee Pollinated

Soil: Runner beans, while being a legume, do best in rich soil and require an ample supply of moisture. As they develop a much more extensive root system than other beans, beds should be prepared to a reasonable depth with well-decomposed manure worked in. A free-draining soil is essential to prevent root rots, which can shorten the lives of the plants.

Growing from Seed

Sow: Direct

Ease of Germination: Easy

Germination Temperature: 15-29 degrees C

Germination Time: 6-16 days

Spacing: 15cm

Harvest: 85 days

Yield: 145g per plant

Seed requires a temperature of at least 12°C to germinate and should be sown in spring after the risk of frost has passed. Seed should be sown at intervals of about 30 cm to suit whatever trellis is being used. During our trials, we rest tomato beds by growing runner beans in the same beds, and they successfully use the same wire trellis. Alternatively, they can be supported with a bamboo wigwam trellis as described for climbing beans. Once established, they should be mulched to deter weeds and retain soil moisture.

Maintenance and Additional Care

While runner beans will reshoot from the ground each spring, their numbers appear to drop off after three to four years. At this time new beds should be established in a different location with fresh seed sown.

Companion Planting

Good companions: Basil, Beetroot, Borage, Brussels Sprouts, Cabbage, Capsicum, Carrot, Cauliflower, Celery, Chilli, Corn, Cucumber, Dill, Eggplant, Lettuce, Marigold, Nasturtium, Parsnip, Parsley, Passionfruit, Peas, Potato, Radish, Spinach, Strawberry, Tomato, Turnip.

Bad companions: Chives, Fennel, Garlic, Gladioli, Kohl Rabi, Onion.

Pests and Diseases

Aphids and mites can be problems at times and should be controlled with sprays if their numbers become excessive.

Perhaps the most serious problem is sudden death of the vines due to soil-borne diseases which, if they occur, necessitate resting the bed for a few seasons and establishing plants elsewhere.

Container Gardening

Runner beans can be grown in pots similarly to other climbing beans. 

Be sure to offer them a trellis or climbing frame as they can grow quite large, forming a spectacular wall of colour if permitted. Make sure the container is large, and you use a premium potting mix designed for vegetables. Place your pot in full sun. Sow plants directly, usually as the base of the frame. Water regularly and when plants start to crop, pick daily to increase production, and lengthen your harvest.

Harvesting

If pods are required for use as snaps, keep harvesting them weekly to promote development of additional flowers and pods.

By far the most common problem encountered with runner beans is the failure of flowers to set pods due to heat. Heavy watering on hot days may encourage some flowers to set in such conditions. Runner beans are dependent on bees for pollination and their presence should be encouraged.

Seed Saving

Seed Longevity: 3-4 years

Isolation Distance: 800m

How to Save Seed: To save seed, allow the pods to dry on the plant. Pick the dry, brittle pods and simply open them up and extract the seed. Seed can be dried further, if required, in a sunny location on some paper towel for 3-4 weeks prior to storage. Once dry, place in a clearly marked envelope and store in a dark, dry location.

Tips and Tricks for Success

• runner beans need tall, sturdy supports to climb up- a trellis, teepee, or obelisk are ideal
• dwarf beans don’t usually need support, although you can insert short twiggy sticks between them to keep them upright and lift the beans off the ground.