Bean support: why & how to use a bean trellis

Growing to well over head height, climbing beans require a structure to grow upon. Learn all about the different types of bean supports available and how to build them.

Being easy to grow and reliable, it is no wonder that beans (Phaseolus) are a favourite of home growers. However, some climbing varieties can grow over 2m tall and need the support of a bamboo frame or a bean trellis to keep them upright. Read on to find out which bean types need a climbing aid and what materials you might need to construct one.

Bean support: do all beans need a climbing aid?

Not all beans require a climbing aid as most dwarf varieties are self-supporting. However, short pea sticks can be used to keep the plants upright and the pods off the soil if required. That said, climbing French beans (Phaseolus vulgaris) and runner beans (Phaseolus coccineus) can reach a height of 2 to 4m and most definitely need a bean support or trellis. Climbing beans tend to twine themselves around their supports but may need a helping hand and tying in at the beginning. If growing space is limited, vertically grown climbing beans can be a good space-saving crop. Nevertheless, any climbing aids used must be stable and sturdy to support the plants when heavily laden and not blow over.

Supporting broad beans (Vicia faba) also depends on the variety as the smaller varieties generally prop themselves and each other up. However, if you grow cultivars that are taller than 40 to 50cm, you can support them with stakes and string.

The best bean supports

Climbing or runner bean supports can take many forms and be made from different materials. You can make a perfectly adequate A-frame bean support from a few bamboo canes and string that will last the season. On the other hand, you can buy a prefabricated metal structure that, while more expensive at first, should last for many years. Whichever structure you choose, the supports for the beans must be less than 3cm wide, as the beans will struggle to twine around them if thicker.

Tip: to remain sturdy all season long, bean supports need to be able to weather the prevailing winds. When using climbing or runner bean poles, insert them 20 to 30cm deep into the ground so that they are secure.

DIY bean trellis

You can make a bean support from various materials you may already have at home or in the garden. You can use bamboo canes, coppiced bean poles or rods of metal rebar for the structure or even repurpose some chicken wire or plastic netting. The materials you use are not too important, as long as the support is robust and tall enough to accommodate the bean’s height when mature.

Bean wigwam

Perhaps one of the easiest bean climbing aids to make is a wigwam cane support, constructed out of bamboo or wooden poles. To build a wigwam bean support, insert 5 to 7 2m poles into the ground in a 75 to 100cm diameter circle and tie them together at the top. To increase stability and provide extra climbing supports for the beans, you can horizontally tie the canes together at 30cm intervals with garden string or twine.

Wigwams for climbing or runner beans are great due to the fact that they are very sturdy on their own and you can make them smaller to fit a container if required. However, when it comes to harvesting the beans, reaching the pods inside the bean wigwam can be tricky.

Tip: to avoid damaging seeds or young plants, it is best to erect bean supports before sowing or planting the beans out.

A-frame

One of the most commonly used climbing or runner bean supports is the A-frame. Looking like a narrow tent, all you need to make an A-frame are some bamboo canes or bean poles and some garden twine. To make this support insert the canes or poles 20cm deep into the soil in two rows roughly 50 to 75cm apart to make the shape of an A. Space the poles along the rows 20 to 30cm apart to give each bean plant enough room to grow and not shade each other. Insert a pole as a crossbar where the vertical poles meet at the top and tie together. For further stability, you can add horizontal bars halfway up the vertical poles.

Even though an A-frame bean support can be slightly laborious to construct and take down at the end of the season, its sloping sides make for easier picking.

You can also use this method for constructing an X-frame, where the vertical poles are placed at more of an angle and are tied together lower down. Being less high, the X-frame can make harvesting more accessible but at the expense of a larger footprint.

Arch trellis

You can also grow climbing and runner beans up and over a metal or homemade arch or tunnel. Metal arches are available to purchase or you can make one out of large metal hoops or semi-rigid water pipes and some netting.

To make a bean tunnel, securely insert the hoops into the ground forming an accessible arch to harvest from. Lay some jute, plastic or wire netting over the hoops and fasten using garden twine.

Being able to walk inside the bean support can make harvesting the beans even easier. However, erecting and removing the trellis arch may take more time than the other methods mentioned.

Once you have chosen your bean support all you need to do is decide which type of climbing bean to grow. Learn all about the different bean varieties to cultivate at home in our separate article.