C.} They are not self pollinating and require pollinators such as bees and butterflies to induce production. Other than the few drawbacks they are relatively easy to grow throughout the US and Canada . They will germinate in cooler soil temperatures , while many other beans will rot.
Runner Beans can be planted outdoors about a week before the average last frost date in early spring, earlier than most bean varieties. A location with full sun is okay in temperate zones, but in hotter regions partial shade is best.
Sow seeds about 1 inch deep in non-compacted well-drained soil . Runner beans grown as climbers should be spaced about 4 -5 inches apart and thinned out , removing 1 of every 4 - leaving only the strongest and healthiest and removing the scraggly ones. Bush or dwarf runner beans should be spaced 5 - 6 inches apart in rows about 2 1/2 feet apart. Spacing may vary somewhat depending on the variety, consult the seed packet or supplier.
If you start them indoors use peat pots, or another biodegradable container a few weeks weeks prior to transplanting outdoors. They frequently suffer from transplant shock - so hardening off is recommended , as well as taking care not to damage the root system when transplanting them.
Keep the seeds moist during the germination stage and maintain a consistent watering as seedlings. They emerge rather quickly, generally under a week, and grow quickly also. An organic mulch will help retain soil moisture while they are growing.
Established Runner beans are not very prone to pest or disease problems. Germinating seeds however become victims of Slugs and occasionally rodents and birds. Excessive watering, can cause root rot.
HARVEST & STORAGE
The flowers are edible and can be harvested as they appear. They are added to many vegetable dishes and salads.
As they mature, they can be harvested like snap beans, pod and all and devoured fresh. For this use they should be harvested while the pods are very young, generally no more than 6 inches , the pod should be flat as opposed to showing the tell tale signs of bulging seeds within.
Harvesting is an continual process once they begin to mature. Harvesting beans continuously, will promote new flowers and beans. You best time to harvest is when the beans become firm and can be easily snapped. If you wait too long, they become fibrous and less desirable. Overripe beans still on the plant are also a drain on the plants development of more beans.
When the seeds are fully formed within the pods they are referred to as Shell beans. The beans should be taken from the pod moist and shiny, before they dry out.
Once the Pods begin to wither, dry out and turn brittle your final harvest for the season has arrived . Gather up remaining pods and store them in a dry location , or shell them right away. They store for up to a year under proper conditions.