Runner Beans

Question 1

What is the latin name for runner beans?

Answer 1

Phaseolus coccineus

Question 2

Explain site and soil selection for runner beans.

Answer 2

• Need a warm sheltered site (avoid frost pockets as they are tender)
• Light shade can prevent flowers aborting (resulting in failure to set fruit)
• Soil should be deep, fertile and moisture-retentive
• Avoid growing in same site every year
• OK to grow in containers.

Question 3

Explain soil preparation for runner beans.

Answer 3

• Primary soil cultivation in autumn prior to sowing the following spring (trench one spit deep, well-rotted stable waste, rots down over winter)
• Secondary soil cultivation two weeks before sowing (fork, level, consolidate, apply Growmore at 70gsqm, create a fine tilth)

Question 4

What temperatures do runner beans require to grow?

Answer 4

• Cool season crop
• Grow best at temperatures between 14 and 29C
• At high temps flowers can abort and pods fail to set.

Question 5

Explain sowing in-situ (outdoors) of runner beans.

Answer 5

• Runner beans are usually sown in-situ in early May
• Can be started earlier in pots under cover
• Wait until soil has warmed to 10-12C and danger of frost has passed before sowing (after 15 May)
• Erect a support of strong 2.5m tall bamboo canes
• Sow beans at base of each cane, depth of 5cm
• 15cm between plants
• 60cm between rows
• Protect with cloche or fleece if needed

Question 6

Explain cultivation of runner beans.

Answer 6

• No need to thin
• Apply a mulch of well-rotted garden compost to reduce weeds and retain moisture
• Weed as necessary
• Watering is critical (5-10L/m2 a fortnight)

Question 7

Explain indoor sowing of runner beans and planting out.

Answer 7

• Sow in individual pots (7cm-9cm), 3 to a pot
• Use loamless or loam-based
• Germinate at 7C-10C in glasshouse or polytunnel
• Germinate in 7-10 days
• After germination, harden off for two weeks

Question 8

Explain harvesting of runners beans.

Answer 8

• Ready to pick 13-17 weeks after sowing
• Pick when pods are 15cm long
• Pick regularly (twice a week)
• Runner beans freeze well.

Question 9

Name three cultivars of runner bean.

Answer 9

• ‘Firestorm’
• ‘Stardust’
• ‘Moonlight’.

Question 10

Name two common pests or diseases of runner beans, including symptoms and a control method.

Answer 10

Black Bean Aphid

• Colonies of small black aphids on tips of stems and flower heads
• Encourage predators like hoverflies; plant attractants like Calendula; wash off; squash.

Halo Blight

• Small, water-soaked spots on leaves of seedlings become dark lesions with a yellow halo. Followed by intervenal chlorosis. Stunted growth, death.
• Do not pre-soak beans, use damp paper instead; avoid overhead watering.