Sweet Pea Seeds: Ruffled, Large-Flowered and Perennial Types Explained

When shopping for sweet pea seeds, you may see descriptions such as “large-flowered sweet peas” or “ruffled sweet peas”. Do these names refer to different species?

No. “Large-flowered” and “ruffled” describe the appearance of the blooms; they are not separate botanical species. The familiar annual sweet pea is Lathyrus odoratus, a species with many cultivars that vary in colour, flower size, petal shape, height and fragrance.

What is Lathyrus odoratus?

Lathyrus odoratus is the botanical name for the annual sweet pea grown for its flowers. It includes traditional cultivars with smaller, simpler blooms as well as cultivars with large, waved flowers. Some grow as tall climbers for the garden and cut flower production; others are shorter and bushier. Because annual sweet peas complete their life cycle in one year, they are grown from seed each season.

The species name tells you which plant it is. To understand what the flowers will look like, check the cultivar or seed mix name and its description.

Are ruffled, large-flowered sweet peas a special type?

They are a recognisable flower style, but the phrase alone does not identify one specific cultivar. “Large-flowered” describes bloom size, while “ruffled” or “waved” describes the petal edges.

Many Spencer type sweet peas have these features. For example, the RHS describes Lathyrus odoratus ‘White Frills’ as a large-flowered Spencer type with waved petal edges. Other cultivars can share the same features while producing different colours or growing on different stems.

Calling seeds “large-flowered, ruffled sweet peas” is therefore a useful description when it accurately reflects the plants. It becomes less helpful if that phrase replaces the cultivar or mix name: the buyer still cannot tell exactly which sweet peas are in the packet.

Our Spring Sunshine sweet peas

The sweet peas in our Spring Sunshine series are Lathyrus odoratus. They have large blooms with softly ruffled, waved petals, so “large-flowered, ruffled sweet peas” describes their appearance well.

Spring Sunshine is the series name, not a different species. The series was selected for cut flower production, with long stems carrying multiple large, waved blooms. Individual Spring Sunshine cultivars offer a choice of flower colours.

Do all sweet peas have large, ruffled flowers?

No. The range within Lathyrus odoratus is part of its appeal. Traditional Grandiflora cultivars generally have smaller, simpler flowers and are often prized for their strong scent. Many Spencer types are chosen for their larger, more waved blooms. Fragrance can also vary, so check the description of the cultivar you are considering.

If you grow sweet peas primarily for bouquets, flower size and stem length may guide your choice. If scent is your priority, look for a cultivar described as strongly fragrant.

Are there perennial sweet peas?

Yes, but they belong to other Lathyrus species. Lathyrus latifolius, commonly called the perennial pea or everlasting pea, returns year after year. Its flowers resemble those of annual sweet peas, but they generally lack the familiar sweet pea scent.

Another perennial species, Lathyrus vernus, forms a compact clump and flowers in spring. It has a very different growth habit from the tall annual sweet peas commonly grown for cutting.

This is why the botanical name matters: Lathyrus odoratus is an annual sweet pea, while species such as Lathyrus latifolius and Lathyrus vernus are perennials.

How to choose sweet pea seeds

For the familiar annual sweet pea, look for Lathyrus odoratus. Then compare the cultivar names and descriptions for colour, fragrance, flower form, height and suitability for cutting. If you want a plant that returns each year, look for a perennial Lathyrus species and check whether fragrance is important to you.

The botanical name identifies the species. The cultivar or series name identifies the selection. Words such as “large-flowered” and “ruffled” describe what its flowers look like.