Autumn sowing season is here. For example, you might think about sowing a range of pea and bean varieties. It is time to think about crops that you can sow this month or next to overwinter in a polytunnel.
One of the most important things to understand as a domestic polytunnel grower is that you will not just be able to cultivate crops through the summer months. Having a polytunnel allows you to grow in your polytunnel garden throughout the whole of the year.
Table of Contents
Why Grow Pea and Bean Varieties Over Winter?
Growing peas and bean varieties over the winter months in a polytunnel can be a great way to increase overall yields from your garden. Of course, you will be able to grow a lot more food if you sow and grow year round than you will if you only sow and grow in the spring and summer.
In a frost-free polytunnel, you can potentially grow a range of crops successfully over the coldest part of the year. Certain peas and beans are suitable candidates to consider.
These legumes also bring additional benefits when they are used for overwintering in a polytunnel. Not only will overwintering these crops provide you with an earlier harvest in the spring, doing so will also help to improve the soil for following crops and help to maintain fertility in your garden.
Peas and beans sown in autumn can provide you with an earlier harvest than when seeds are sown in the spring. But more than this, the convenience of the timings can work out better for polytunnel growers trying to make the most of time and space with successional sowing throughout the year.
I personally like to sow beans and peas for overwintering as they can then be harvested early enough to be replaced with summer crops like tomatoes and peppers, for example, in the garden rotation plan.
Choosing Pea and Bean Varieties
If you are considering growing legumes in your polytunnel garden over the winter months then it is very important to choose the right pea and bean varieties to grow. Not all peas and certainly not all beans can survive the conditions over the coldest part of the year. So it is important to choose hardier options.
The peas that you will choose for autumn sowing will be round-seeded varieties of Pisum sativum (garden peas). Those varieties with smooth, round seeds will generally be better for winter growing and cope better with cooler and wetter conditions than those varieties that have smaller, wrinkled seeds.
The beans that we are taking about in this article are fava beans, commonly known as broad beans in the UK. These are Vicia faba, and there are several key varieties of this plant most frequently recommended for winter growing because they are hardy enough, again, to cope with cooler and wetter conditions.
Pea Varieties for Autumn Sowing
There are a number of different pea varieties that I would recommend for winter polytunnel growing in the UK, which may also work in a milder and more sheltered garden outside.
- Pisum sartivum ‘Avola’ – a hardy first early pea, tender pods with around 8 seeds.
- P. sativum ‘Amelioree d’Auvergne’ – round seeded versatile climber – pick small, for sweet flavour.
- P. sativum ‘Douce Provence’ – bushing, requires little or no support, small but very sweet peas.
- P. sativum ‘Feltham First’ – very hardy, once of the earliest varieties to crop.
- P. sativum ‘Glory of Devon’ – rare heirloom, peas small but very sweet.
- P. sativum ‘Hatif d’Annonay’ – dwarf variety, very early.
- P. sativum ‘Meteor’- quick maturing dwarf pea to 60cm.
- P. sativum ‘Serpette Guilloteau’ – traditional climbing pea to 1.5m, pick small for sweetness.
Personally, I have grown several of the above in my polytunnel, and would particularly recommend ‘Douce Provence’ and ‘Meteor’ – both of which have performed well where I live here in Scotland in my unheated polytunnel.
Broad Bean Varieties for Autumn Sowing
Broad bean varieties commonly considered for Autumn sowing in the UK are:
- Vicia faba ‘Aguadulce Claudia’ – often considered the best variety for winter sowing.
- V. faba ‘Superaguadulce’ – often considered the hardiest broad bean variety there is.
- V. faba ‘Witkiem Manita’ – usually sown in spring but this variety also works for autumn sowing in a polytunnel garden.
I have found all of the above to be productive and pretty reliable when they are sown in autumn to overwinter in my polytunnel garden.
Overwintering Broad Beans in September or October
I tend to sow my broad beans indoors in modules or soil blocks in September and transplant them into my polytunnel in early October. They usually go into the space vacated by some of the summer crops that are nearing the end of their productive period – like tomatoes or courgettes, for example.
While some succeed in direct sowing their broad beans, I generally find that it is best to sow indoors and transplant the young beans to the polytunnel a little later because of pests.
Mice and voles can sometimes eat seeds sown in the polytunnel in autumn before they get the chance to germinate – while young plants are a little easier to protect with cloches and chilli powder that keep these pests away. Larger plants can be protected with larger scale coverings such as fruit cages to prevent any damage from pests.
Peas that Can Withstand the Cold
I sow peas for winter indoors at around the same time. Again, it is easier in my particular circumstances to sow indoors and transplant peas to the polytunnel relatively early in their growth.
I do direct sow peas sometimes in the spring and early summer. But do find that autumn sowings are particularly vulnerable to pests which is why it is easier to sow indoors and transplant at this time of the year.
The thing to remember with peas is that it is actually winter wet rather than winter cold that can cause the biggest problems.
Round peas don’t have as many fissures for water to sit in, and so are less prone to rot. Of course, in a polytunnel, you have much greater control over the water availability, so you may have more choice when it comes to variety. But I still find it best to stick with the varieties best known to be good for overwintering.
How to Keep Peas and Beans Healthy
Peas and beans don’t take a lot of work at any time of year and are relatively easy crops to grow. In winter, as in summer, you need to think about water, fertility, and support for the plants that you cultivate. Remember that some peas in particular are much, much taller than others so will require more and higher supports.
Remember that you should take care to keep the soil healthy, as this is the root of healthy plants. It should be moist but free draining, with plenty of organic matter. Make sure that even in the depths of winter, you make regular visits to the polytunnel to check on your plants.
How to Grow Winter Field Peas and Beans as a Green Manure
Even if you are not too concerned about obtaining an earlier harvest of peas or beans next year, you may still wish to grow field peas or field beans as a green manure. Field peas and field beans are commonly used as cover crops in agriculture and we can also use them in a garden.
I have grown field beans outdoors through the winter, even in a more exposed location on my property.
The beans are slightly smaller than those broad beans cultivated for food, and the yields are lower, but their hardiness means that they can be very useful in covering the soil over winter and boosting fertility as a green manure. And you can still leave a few plants and harvest a few beans for culinary use if you wish.
When To Harvest Overwintered Pea and Bean Varieties
Peas and beans will largely just sit there over much of the winter before they erupt into new growth again in the spring. The harvest will only be a little earlier than it would have been had you sown seeds in the spring.
In my experience, overwintered pea and bean varieties are ready to harvest around a month before spring sown peas and beans. But remember, you don’t overwinter these legumes predominantly to get an earlier harvest, but rather for other reasons like increasing overall yield or to maintain or boost soil health within your garden. For more advice on growing other types of beans in your polytunnel, such as runner beans, here is how to grow runner beans as well as growing runner beans to dry.
What does “overwintering” mean when it comes to pea and bean varieties?
Overwintering refers to the practice of sowing pea and bean varieties in the fall so they can establish themselves before winter. These plants then go dormant during the coldest months and resume growth in early spring, often producing earlier and more abundant harvests compared to spring-sown crops.
Which pea and bean varieties are best suited for overwintering?
For peas, hardy varieties like ‘Meteor’ and ‘Feltham First’ are popular choices for overwintering. When it comes to beans, broad beans (fava beans) are commonly overwintered, with varieties like ‘Aquadulce Claudia’ and ‘Super Aquadulce’ being particularly resilient to cold conditions.
How do I protect overwintered pea and bean varieties from frost and extreme cold?
Protection is essential for successful overwintering:
Cloches or Fleece: Use garden cloches or horticultural fleece to protect young plants from frost.
Mulch: A thick layer of straw or leaf mulch can provide insulation against extreme cold.
Location: Plant in a sheltered spot, away from prevailing winds and where they can receive winter sunlight.
Watering: Ensure the soil is moist but not waterlogged. Overly wet soil can lead to rot during cold months.
Real Seeds. (n.d.) Peas. [online] Available at: https://www.realseeds.co.uk/peas.html [accessed 29/09/23]
Elizabeth Waddington is a writer and green living consultant living in Scotland. Permaculture and sustainability are at the heart of everything she does, from designing gardens and farms around the world, to inspiring and facilitating positive change for small companies and individuals.
She also works on her own property, where she grows fruit and vegetables, keeps chickens and is working on the eco-renovation of an old stone barn.
To get in touch, visit https://ewspconsultancy.com.