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Are sweet peas hardy?

Who doesn’t love sweet peas? Those fragrant, colourful displays are simply wonderful. but if you are new to growing sweet peas you may well be wondering how hardy they are, if they are hardy at all. Well, let me help you out as we find out exactly how hardy sweet peas are.

So the short answer is that sweet peas are hardy, they can tolerate cold weather pretty well. In fact, it is common practice to overwinter sweet peas. What this means is that seeds are started in the autumn in a polytunnel, greenhouse or other sheltered spot and then grown over winter, ready to explode in the following spring.

Sweet peas won’t do too well if left outside over winter though, they can handle colder weather and maybe even a few touches of frost if they are larger plants. They cannot survive a full winter outside though and do need to be in something like a polytunnel for the really cold months.

Sweet Peas Growing Up Stick Supports
Sweet Peas Growing Up Stick Supports

For regular growing of sweet peas from spring onwards you can treat sweet peas as a hardy plant. They are fairly tough and will grow through most conditions and tolerate spring cold fairly well.

What sweet peas really need in order to bloom though is sunlight. As long as they get plenty of sun and enough water they will be happy plants, even if it is a little cold still.

Mixed colours of sweet pea flowers
Mixed colours of sweet pea flowers

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.