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Are sweet peas frost hardy?

If you are growing sweet peas then you will probably want to get them planted out as early as possible to get those gorgeous blooms as quickly as possible. That will lead to one big question, will your sweet peas survive a few touches of frost or do you need to wait until all risk of frost has passed before planting them out? Essentially you want to know if sweet peas are frost hardy? Well, let’s have a look.

How much frost can sweet peas survive?

Sweet peas are generally frost hardy, they can survive the occasional frost and be just fine. For most gardeners in the UK, this means they can plant them out in spring and not have to worry about cold weather affecting them too much.

However, they are not completely impervious to frost. If the weather is really cold, abnormally so for more parts of the UK, in the region of below -4 degrees then sweet peas will not be able to survive.

Sweet peas will also not cope well with extended periods of cold weather or snow. So while they can shrug off the occasional late spring frost they will not be able to survive a prolonged period of cold or snow covering that hung around for a week or so.

Sweet Peas in Archway
Sweet Peas in Archway

What we have learnt here is that you can plant sweet peas out in spring and they should be fine. Unless we had really cold weather or a prolonged snow storm they should be able to handle the cold weather cust fine.

They are frost hardy annuals but are not capable of surviving through the depths of winter. If you are growing your sweet peas from seed then they will be capable of surviving all but the most extreme spring frosts.

More on Sweetpeas

sweet peas, (Lathyrus odoratus) are a flowering plant belonging to the legume family. They are an annual flower that loves to climb and spread, in the right conditions and with the correct support they can grow to 2 and a half meters tall!

Unlike many other legumes which are grown to be eaten, sweet peas are grown for purely aesthetic reasons. There is evidence to suggest that the pea seeds from a sweet pea plant are actually toxic to humans and not fit for consumption even if this was desired.

Sweetpea FAQ’s

Are sweet peas perennial?

No sweet peas are an annual plant, they will not come back year after year.

Can you eat sweetpeas?

No, sweet peas are grown purely for their looks. Unlike many other legumes, they are actually toxic to humans if consumed.

Are sweet peas poisonous to pets?

Yes, as they are poisonous to humans they are also poisonous to pets, so make sure you keep an eye on your pets when they are hovering around sweet peas.

How high can sweet peas grow?

With the proper support, sweet peas can grow to 2m or even slightly above!

When do you grow sweet peas?

The traditional season for sweet peas is June and July but with the right care and attention, they can be both started earlier and grown later into the season. Regular deadheading of sweetpeas can massively prolong their flowering period.

How to germinate sweet peas?

I like to soak my sweet pea seeds in water for 24 hours before planting them in a seed tray. This soaking helps to break down the tough shell around the seed allowing them to germinate better.