Seed Swaps

Sweet pea       

Lathyrus odoratus

Sweet pea is a plant which belongs to the Lathyrus (Sweet pea) genus.

Sweet peas are annual climbing plants that produce many beautifully fragrant frilly flowers. Sweet peas are shades of pink, red purple cream and white and are grown for the garden and for cut flowers.

Blooms typically mature to a diameter of 3.0 cm (1.17 inches imperial) and produce a floral fragrance, whilst displaying in these approximate colours:   Carmine red and   Bright Purple and   Bright pink. When ripe, fruit appear in these approximate colours:   Dark brown. Leaves appear approximately as a   Sea green and   Kelly green

Sweet pea grows as an annual and is a non-edible flower / herb. Being an annual plant, it tends to grow best over the course of a single year.

Sweet pea normally grows with a vine habit to a mature height of 1.50 metres (that's 4.88 feet imperial). This plant tends to bloom in late summer, followed by first harvests in late summer.

Try planting Sweet pea if you'd like to attract bees to your garden.

Sweet Pea Mixture, Spencer Special Mix, Cupani, Royal Family and Mammoth Mix are some of the most popular varieties of Sweet pea for home gardeners to grow.

As Sweet pea is a low maintanence plant, it is great for beginner gardeners and those that like gardens that don't need much overseeing.

This plant info is provided by the myfolia gardener's wiki. All details about Sweet pea have been kindly provided by our members.

How to grow Sweet pea

  • Partial Sun

  • Full Sun

  • Medium

Guide the peas up the support tying in if necessary
When the flowers begin it is very important to keep picking them and do not let any go to seed or the flowers will stop being produced
Picking all the open flowers or almost open flowers on the same day each week is best. It only takes a day or two for more buds to open and colour to return to the garden until the next week.

Plant in a location that enjoys partial sun / full sun and remember to water moderately. Keep in mind when planting that Sweet pea is thought of as very hardy, so this plant will survive though longer winters with little or no damage.

See our list of companion Plants for Sweet pea to see which plants you should plant in close proximity to encourage growth.

Growing Sweet pea from seed

Plant three seeds in a 7cm pot and germinate at 20C. in early spring Once germinated the plant can be grown on in cooler conditions, for example a cold frame. Lift the lid of the cold frame when ever possible to keep conditions cool and the plants short

Look to ensure a distance 7.8 inches (20.0 cm) between seeds when sowing - bury at a depth of at least 0.39 inches (1.0 cm) deep. Soil temperature should be kept higher than 10°C / 50°F to ensure good germination.

By our calculations*, you should look at sowing Sweet pea about 42 days before your last frost date .

Transplanting Sweet pea

Transfer to a cold frame and grow on.
Pinch out the tops when there are three leaves, this will make more side shoots and hopefully more flowers
Plant out in a sunny position with canes or net for support as the soil warms up

Ensure that temperatures are mild and all chance of frost has passed before planting out, as Sweet pea is a very hardy plant.

Harvesting Sweet pea

Once a week(easy to remember if you always do it on the same day!) Pick ALL the flowers and (almost) flowers and use them in your home.
The plant quickly grows some more and it is not without colour for long. This way the plants will last all season and you will have flowers in vases too

Seed Saving Sweet pea

If you want to save seed for next year, towards the end of the season select your stem or stems and mark it with coloured wool (so you don’t cut it off before it is ready!)
Allow the pod to swell before cutting and drying.

Seed viability is five years.

How long does Sweet pea take to grow?

These estimates for how long Sweet pea takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.

Start logging and journaling your observations to participate!

Days to Germination How long does it take Sweet pea to germinate?
12 days

Average 12 days | Min 2 days | Max 36 days (270)

Days to Transplant How long until I can plant out Sweet pea?
+ 38 days

Average 38 days | Min 4 days | Max 90 days (107)

Days to Maturity How long until Sweet pea is ready for harvest / bloom?
+ 98 days

Average 98 days | Min 3 days | Max 193 days (564)

Total Growing Days How long does it take to grow Sweet pea?
= 148 days

When should I plant Sweet pea?

Our when to plant Sweet pea estimates are relative to your last frost date.

Enter your frost dates and we'll calculate your sowing and planting dates for you!

When to sow The number of days to sow Sweet pea before or after your last frost date.
42 days before Last Frost Date

Sweet pea Etymology

The botanical epithet is from the Latin odoratus meaning “fragrant”

Other names for Sweet pea


Lathyrus odoratus L.

Misspellings: Lathyrus adoratus, sweetpea, sweet-pea, sweatpea, sweat pea

Latest Sweet pea Reviews

  • See previous.

    0 stars

    the4ts about growing Sweet pea
  • Got rid of them as they were awful! Half died off before the other half flowered. The few flowers that did come through were white and very pretty though. Won’t grow again. Too much dead plant though and required a lot of pruning to get rid of.

    0 stars

    the4ts about growing Sweet pea
  • I bought a sweetpea variety named fire and ice.They are suppose to be 50% red 50%white. They are pink and white on the same flower.I know they are “painted lady” The seed company made a mistake

    5 stars

    foxglove30 about growing Sweet pea 'High Scent'

See all Sweet pea reviews and experiences »


Sweet pea Forums

  • Sweet Peas

    Discussion group for growers and fans of Sweet Peas (Lathyrus odoratus) which have been a popular garden plant for ce...

    26 members / 23 topics