Create Your Garden

Lathyrus odoratus (Sweet Pea)

Sweet Pea

Lathyrus Odoratus, Sweet Pea, Annual plant, Fragrant Plant, Climbing plant,Annual Flowers, Fragrant Flowers Climbing Flowers

Lathyrus odoratus, commonly known as Sweet Pea, is a fragrant annual plant with a wide range of colorful flowers, ideal for adding beauty and fragrance to gardens, borders, containers, and trellises.

What is Sweet Pea?

Lathyrus odoratus, commonly known as sweet pea, is native to the Mediterranean region, specifically Sicily, southern Italy, and the Aegean Islands.

Description: Sweet peas are a beloved garden classic, admired for their vibrant colors and intoxicating scent. The plant is an annual flowering vine that grows on slender, green stems.

Growth Habit: Sweet peas have a sprawling or climbing habit, with tendrils that readily twine around any available support. It’s a fast grower, especially in cool weather, making it a fantastic spring climber.

Size: As bushy annuals, they grow from 8 inches to 3 feet tall (20-90 cm). As climbing annuals, they can grow up to 6-8 feet (180-240 cm) or more in a single season. Without support, they would grow in a bushy mound to 28 inches tall (70 cm).  Dwarf varieties are also available, suitable for containers or small spaces.

Flowers: The flowers are perhaps their most impressive feature. They have one large, upright, round petal (banner or standard), two narrow side petals (wings), and two lower petals forming a boat-shaped structure (keel). They come in a range of colors, including white, pink, red, purple, and blue. The flowers are usually gathered in clusters and are famously fragrant. They make magnificent cut flowers and great bouquets for your home.

Foliage: Sweet pea plants have delicate, pinnately compound leaves, which consist of one to three pairs of leaflets and a terminal tendril that aids in climbing.

Blooming Season: Sweet peas bloom from late spring to fall. They bloom best in cool, mild climates where they enjoy a long blooming season.

Hardiness: Sweet peas are annuals and can tolerate a light frost but dislike hot, humid conditions.

Uses: Sweet peas are popular in cut flower arrangements due to their attractive flowers and sweet fragrance. They are also commonly used to cover fences, trellises, or archways in gardens.

Pollinators: The flowers are visited by a variety of pollinators, particularly bees and butterflies, who are attracted to the flowers’ sweet fragrance and vibrant colors.

Toxicity: Sweet peas are not edible. They are toxic if ingested by both humans and pets. Their seeds are particularly high in a neurotoxic amino acid known as ODAP.

Deer: Sweet peas are often resistant to deer, who generally avoid eating them due to their toxicity.

Invasiveness: Sweet peas can self-seed prolifically under ideal conditions. They are considered invasive in New Zealand and ‘possibly invasive’ in the Dominican Republic. However, in their native range, they are listed as Near Threatened, as they are subject to wild collection threat due to their commercial value. Remove spent flowers before they set seed if you wish to prevent self-seeding.

Key Facts: Sweet peas were first brought to England in the 17th century and have been a favorite in English gardens ever since. Today, there are hundreds of cultivars available, offering a broad range of colors and flower forms. Despite the common name, sweet peas are not related to edible peas.

Guide Information

Hardiness 2 - 11
Heat Zones 1 - 8
Climate Zones 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
Plant Type Annuals, Climbers
Genus Lathyrus
Exposure Full Sun
Season of Interest Spring (Late)
Summer (Early, Mid, Late)
Fall
Height 8" - 8'
(20cm - 240cm)
Spread 2' - 3'
(60cm - 90cm)
Maintenance Low
Water Needs Low, Average
Soil Type Loam, Sand
Soil pH Acid, Alkaline, Neutral
Soil Drainage Well-Drained
Characteristics Cut Flowers, Fragrant, Showy
Tolerance Deer
Attracts Bees, Butterflies
Landscaping Ideas Wall-Side Borders, Arbors, Pergolas, Trellises, Beds And Borders, Patio And Containers
Garden Styles City and Courtyard, Informal and Cottage, Mediterranean Garden
Lathyrus × hammettii ‘Turquoise Lagoon’ (Sweet Pea)
Lathyrus odoratus ‘America’ (Sweet Pea)
Lathyrus odoratus ‘Apricot Queen’ (Sweet Pea)

Why Should I Grow Sweet Pea?

There are several reasons why you might consider growing Sweet Pea in your garden:

Fragrant Flowers: One of the most compelling reasons to grow sweet peas is their fragrance. They are known for their sweet, heady scent, which can fill a garden or indoor space when used in cut flower arrangements.

Attractive Blooms: Sweet peas are prized for their vibrant, colorful flowers. They can provide an array of colors to the garden, from soft pastels to rich, deep hues.

Pollinators: The flowers are popular with pollinators, attracting bees and butterflies to your garden, which can help with the pollination of other plants.

Climbing Habit: With their climbing growth habit, they are excellent for adding vertical interest to your garden. They can be used to cover fences, trellises, or arches.

Cut Flowers: Sweet peas are excellent for cut flower arrangements. Their long stems and fragrant blooms make them a popular choice for vases and bouquets.

Easy to Grow: Sweet peas are fairly easy to grow from seed and can be a fun plant for beginners or children to try growing.

Early Spring Color: Sweet peas are one of the earliest flowering climbers, bringing color and fragrance to the garden in late spring and early summer.

However, always bear in mind their toxicity – all parts of the plant, particularly the seeds, are toxic if ingested. This should be considered if you have pets or young children. Also, in some areas, sweet peas may become invasive through self-seeding, so it’s important to manage them appropriately.

Lathyrus odoratus ‘Matucana’ (Sweet Pea)
Lathyrus odoratus ‘Charlie’s Angel’ (Sweet Pea)
Lathyrus odoratus ‘Gwendoline’ (Sweet Pea)

Garden Design with Sweet Pea

Sweet peas (Lathyrus odoratus) offer a wonderful mix of vivid colors and heady fragrances that can significantly enhance your garden design. Here are a few design ideas:

Vertical Interest: Use sweet peas to add vertical interest to your garden. They are climbers and can be grown on trellises, archways, fences, or pergolas. This can draw the eye upwards and create a sense of height and depth in the garden.

Cottage Garden: Sweet peas are a classic choice for a cottage garden. You can mix them with other traditional cottage garden plants like roses, foxgloves, and delphiniums. The colorful and fragrant blooms contribute to a sense of casual abundance that’s typical of cottage gardens.

Cut Flower Garden: If you like to bring fresh flowers indoors, consider including them in your cut flower garden. Their long stems, vibrant colors, and lovely fragrance make them perfect for bouquets and floral arrangements.

Container Gardening: There are dwarf varieties that are well-suited to container gardening. You can place the container in a prominent location to make the most of their eye-catching blooms and delicious fragrance.

Pollinator Garden: The blossoms attract bees, butterflies, and other pollinators. Including them in your garden can therefore help to increase its biodiversity.

Spring Garden: Sweet peas bloom in late spring and early summer, adding color and fragrance at a time when many other plants are only just beginning to grow.

Edging Paths: Plant them along garden paths or entrances. As you pass by, you can enjoy their delightful scent and vibrant blooms.

Remember to provide a support structure for your plants to climb on, and to keep them well-watered, especially during dry spells. And don’t forget to deadhead spent blooms regularly to prolong the flowering period.

Lathyrus odoratus ‘Dorothy Eckford’ (Sweet Pea)
Lathyrus odoratus ‘Senator’ (Sweet Pea)
Lathyrus odoratus ‘Cupani’ (Sweet Pea)

Companion Plants

Sweet Peas are wonderfully versatile and can be successfully paired with a range of companion plants. Here are some ideas:

Climbing Roses: The combination of sweet peas and climbing roses on an arbor or trellis can be quite stunning. Sweet peas bloom earlier than most roses, providing color until the roses take over.

Delphiniums: Tall delphiniums can provide a colorful backdrop. Their similar growth habit and vibrant blooms can create a harmonious display.

Foxgloves: Foxgloves can complement the height of sweet peas and provide a beautiful contrast with their bell-shaped flowers.

Annuals: Other annuals like marigolds, zinnias, or cosmos can provide a continuous display of color when planted alongside sweet peas.

Herbs: Fragrant herbs like lavender or rosemary can complement the sweet scent of sweet peas.

Clematis: A less vigorous clematis variety could share a support with sweet peas, providing a longer season of interest as many clematis varieties bloom later in the summer.

Grasses: Ornamental grasses can provide a contrasting texture and form, both complementing and highlighting the vibrant colors of sweet peas.

Remember that sweet peas like a sunny position and well-drained soil, so choose companions with similar growing requirements. And consider the mature size of all plants to ensure there’s enough space for everyone to grow without becoming crowded.

Companion Plants for Sweet Pea

Rosa (Rose)
Clematis
Digitalis (Foxglove)
Lavandula angustifolia (English Lavender)
Papaver orientale (Oriental Poppy)

Growing Tips

Growing sweet pea, can be a rewarding experience with their beautiful, fragrant blooms. Here’s a step-by-step guide on how to grow them:

Choosing a Location: Sweet peas need full sun or light shade. They prefer cool, moist locations and might struggle in hot, dry climates. They also need good air circulation, but avoid areas with strong winds that could damage the vines. Sweet Peas are happiest with their heads in the sun and roots deep in cool, moist soil. When possible, plant low-growing annuals before them to shade their roots.

Soil Preparation: They prefer well-drained soil enriched with plenty of organic matter like compost or well-rotted manure. The pH should be neutral to slightly alkaline. A heavy application of mulch will help keep the roots cool and moist.

Sowing Seeds: They can be sown directly into the garden or started indoors 6-8 weeks before the last expected frost. Soak the seeds in water for 24 hours before planting to help speed up germination.

Planting: Plant seeds about 2 inches (5 cm) deep and 2-3 inches (5-7 cm) apart. Once planted, germination can take 7 to 15 days, depending on the soil temperature. If starting indoors, transplant the seedlings outdoors when they are 4-5 inches (10-12 cm) tall and the danger of frost has passed.

Providing Support: As sweet peas are climbing plants, they need support to grow. This could be a trellis, netting, or bamboo canes. Ensure the support is in place at the time of planting to avoid damaging the plants later.

Watering: Keep the soil evenly moist but not waterlogged. Sweet peas have deep roots, so a thorough watering once a week is often better than frequent, shallow watering.

Fertilizing: Feed every 4 weeks with a balanced flower fertilizer to promote vigorous growth and plentiful blooms.

Pruning and Training: Regularly pinch out the tips of young plants when they are about 6 inches (15 cm) tall, to encourage bushier growth, not before, or you will promote side-shoot development. Tie the shoots to their supports to help guide their climb. Do not hesitate to cut flowers for your bouquets, as this will force your plants to produce additional stems for bloom.

Deadheading: Regularly remove spent flowers to encourage more blooms and to prevent the plants from setting seed, which can reduce flowering.

Pest and Disease Control: Monitor for pests like aphids, slugs, and snails, and diseases such as powdery mildew, rust or gray mold. Use appropriate organic or chemical controls as necessary.

Harvesting: For the best fragrance, cut the flowers in the early morning or late evening, and place them directly into room-temperature water.

Remember, all parts of the sweet pea plant, especially the seeds, are toxic if ingested, so keep them out of reach of children and pets.

Compare All Lathyrus
Compare Now
Guides with
Lathyrus
While every effort has been made to describe these plants accurately, please keep in mind that height, bloom time, and color may differ in various climates. The description of these plants has been written based on numerous outside resources.

Guide Information

Hardiness 2 - 11
Heat Zones 1 - 8
Climate Zones 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24
Plant Type Annuals, Climbers
Genus Lathyrus
Exposure Full Sun
Season of Interest Spring (Late)
Summer (Early, Mid, Late)
Fall
Height 8" - 8'
(20cm - 240cm)
Spread 2' - 3'
(60cm - 90cm)
Maintenance Low
Water Needs Low, Average
Soil Type Loam, Sand
Soil pH Acid, Alkaline, Neutral
Soil Drainage Well-Drained
Characteristics Cut Flowers, Fragrant, Showy
Tolerance Deer
Attracts Bees, Butterflies
Landscaping Ideas Wall-Side Borders, Arbors, Pergolas, Trellises, Beds And Borders, Patio And Containers
Garden Styles City and Courtyard, Informal and Cottage, Mediterranean Garden
Compare All Lathyrus
Compare Now
Guides with
Lathyrus

Related Items

Please Login to Proceed

You Have Reached The Free Limit, Please Subscribe to Proceed

Subscribe to Gardenia

To create additional collections, you must be a paid member of Gardenia
  • Add as many plants as you wish
  • Create and save up to 25 garden collections
Become a Member

Plant Added Successfully

You have Reached Your Limit

To add more plants, you must be a paid member of our site Become a Member

Update Your Credit
Card Information

Cancel

Create a New Collection

Sign Up to Our Newsletter

    You have been subscribed successfully

    Join Gardenia.net

    Create a membership account to save your garden designs and to view them on any device.

    Becoming a contributing member of Gardenia is easy and can be done in just a few minutes. If you provide us with your name, email address and the payment of a modest $25 annual membership fee, you will become a full member, enabling you to design and save up to 25 of your garden design ideas.

    Join now and start creating your dream garden!

    Join Gardenia.net

    Create a membership account to save your garden designs and to view them on any device.

    Becoming a contributing member of Gardenia is easy and can be done in just a few minutes. If you provide us with your name, email address and the payment of a modest $25 annual membership fee, you will become a full member, enabling you to design and save up to 25 of your garden design ideas.

    Join now and start creating your dream garden!

    Find your Hardiness Zone

    Find your Heat Zone

    Find your Climate Zone