Which do you like more? The snappy freshness of immature bean pods, the sweet, creamy taste of shell beans or the versatility of dry beans? Either way, growing beans in your garden isn’t that hard provided you know the types of beans that need a trellis and when to trellis them.
Beans belong to the Fabaceae family of flowering plants and can be bush beans or pole beans. As you can tell from their name, bush beans grow closer to the ground, you don’t need to trellis them.
Pole beans, also known as vine beans or indeterminate beans, grow taller, reaching heights of up to 15 feet, and they need a trellis. More than supporting the plant’s growth, a trellis can increase a pole bean’s yield and its resistance to pests by improving sun exposure and air circulation.
Many bean plants come in both bush and pole varieties, so it’s important to check which type you get.
Which beans need a trellis?
Beans you need to trellis include pole beans such as green beans and subtypes like kidney beans, pinto beans, and haricot verts, as well as fava beans, runner beans, black eye peas, and garbanzo beans.
Before we dive into bean varieties, it’s important to get some terms right. The immature pods of beans are called snap beans while the immature seeds are called shell beans. These are harvested within 50 to 60 days after sowing depending on the variety.
Meanwhile, dry beans are the mature seeds of the plant. They are harvested around 70 to 150 days after sowing. Some pole beans are grown for their pods, others for their seeds.
Now let’s look at the most commonly grown bean varieties that need the support of a trellis.
Green beans (Phaseolus vulgaris)
When we talk about green beans, we talk about Phaseolus vulgaris, a herbaceous annual that yields many varieties of beans depending on the cultivar and harvesting method.
It includes the broadest category of pole beans but as we’ll see, not all varieties are necessarily green. Green beans include the following pole bean subtypes.
Tender and thin, haricot verts are best harvested young. They provide a more delicate taste than other green beans.
Romana or Italian beans
These wide beans have pods up to 8 inches long. You can cook the whole pod for a sweet side dish or use it in combination with tomatoes and other vegetables.
Asian long beans
This variety of pole beans yields slender pods that can be 18 inches long. This plant can be heavier than other pole beans, so it needs a reliable trellis.
Yellow wax beans
Yellow wax beans are a variety of green beans that lacks chlorophyll. That doesn’t make them any less nutritious though. Their mild flavour makes them a versatile ingredient in many vegetable dishes.
Purple beans may catch the eye, but boil them in a pot and they will fade to green, a colour that betrays their origins.
So far, we’ve talked about green bean varieties grown for their pods. Kidney beans are also harvested from the Phaseolus vulgaris annual plant but they are mature seeds. These are allowed to dry in their pods and harvested only after they have fully matured.
Black beans are not as common as other varieties, but if you decide to grow them, make sure to trellis them.
Navy beans are not navy in colour but white. They are small haricot beans.
Yet another dry bean variety of the green bean plant, pinto beans also need a trellis.
Fava beans (Vicia fava)
Fava beans are broader and bigger than green beans. They hail from the Mediterranean but grow well in cool weather too.
Runner beans (Phaseolus coccineus)
Runner beans are grown for their savoury dry butter beans. They can easily grow to 8 feet, so you want to trellis them for optimal growth. This plant includes the scarlet runner variety.
Black eye peas or Cowpeas (Vigna unguiculata)
Despite their name, black eye peas are a bean, not a pea. They need vertical support to grow and yield a bountiful harvest.
Chickpeas (Cicer arietinum)
The highly nutritious chickpeas—did anyone say hummus?—are also called garbanzo beans, which gives away their origins.
When to trellis beans
The best time to trellis beans is before sowing the seeds. Otherwise, you may disturb the sensitive roots. It’s a good idea to stake the trellis first and then plant the seeds around it. You can use a simple A-frame trellis, a tepee trellis or a cattle panel to provide ample space for the beans to grow.
Ideally, the trellis should be at least 1 foot taller than the average height you expect the plant to reach at maturity. This will provide it with enough support to grow unhindered.
Most pole beans are sowed after the last frost so start thinking about the trellis early.
If you’ve already sowed the seeds, don’t worry. You can still install a trellis, only be careful not to upset the ground where the seeds are growing. Go for a wall trellis, stand-alone trellis, or any other trellis that doesn’t require stacking within the sowing area.
Pole beans grow fast, so make sure the trellis is firm enough to support the weight of the plant. You don’t want to have to fix it once the plant starts spreading on it.
Tip: A pole bean trellis doesn’t have to serve only a functional purpose. You can use it as a screening fence, especially if you grow a companion plant like nasturtium alongside the beans. Nasturtium can improve the health and flavour of the beans by attracting blackflies that may otherwise target the bean plant.
Picking the right trellis for beans
The best trellis for beans is at least 5 to 6 feet tall, weather-resistant, and provides good access to the pods for harvesting. It should be wind-resistant and not require much maintenance.
Pole bean trellises need to be able to withstand wind. Even better, place them in a spot where they are not exposed to strong wind, such as close to a wall.
You can buy a trellis for beans or make your own from readily available materials including stakes, cattle mesh, bamboo sticks, or wood.
A bountiful harvest
Taking the time to support your pole beans is well worth it as you can harvest many varieties of pods every two weeks during the summer. If you prefer dried beans, you’re looking at a nutritious food rich in protein, fibre, and micronutrients like potassium, folate, and magnesium.
Beans are one of the healthiest foods you can eat, and with a trellis, you can get a bountiful harvest while increasing your vertical gardening space. So, time to add one?