Sweet peas, known for their vibrant colors and delightful fragrance, are a gardener's favorite. These annuals, including varieties like 'Cupani' and 'Old Spice,' offer a range of hues from maroon to lavender. While their beauty is captivating, sweet peas can be challenging to grow, requiring specific soil conditions and early sowing for successful germination.
- Common Names: Annual Sweet Pea, Everlasting Pea, Perennial Pea
- Scientific Name: Lathyrus odoratus
- Plant Type: Herbaceous perennial vine
- Plant Height: 4-10 feet
- Growing Difficulty: Medium
- Growing Time: 7-15 days for germination
- Bloom Time: Spring, Summer, Fall
- Temperature: Prefers cool climate, fades above 65°F
- Hardiness Zone: 2-10 (Find your hardiness zone here)
- Sunlight: Full Sun, Partial Shade
- Soil pH: Alkaline/Basic
- Watering Frequency: Keep soil moist
- Plant Spacing: 3-6 feet apart
Different Methods to Grow Sweet Peas
Sowing Seeds Indoors
Start seeds in a seed tray in early spring, about 6-7 weeks before the last frost. Soak seeds overnight and lightly score the outer shell to aid germination. Plant seeds half an inch deep in individual cells. Transplant seedlings to larger pots and then outdoors when the soil can be worked.
- Pros: Early start, controlled environment, better germination rates.
- Cons: Requires more effort and space for seed trays and transplanting.
Sowing Seeds in the Ground
Plant seeds in very late winter or early spring in colder zones, or in late fall in milder climates. Choose a well-drained site with alkaline soil. Prepare the soil with compost or well-rotted manure. Soak seeds for 24 hours before planting and nick the seeds to speed sprouting. Plant seeds in a deep trench and cover them with soil.
- Pros: Less effort, no need for transplanting, natural growth conditions.
- Cons: Risk of poor germination, exposure to pests and weather conditions.
Ideal Soil and Location Requirements
Sweet peas thrive in rich, well-drained soil with high organic matter. They prefer full sun exposure but benefit from having their roots shaded by low-growing plants. Ensure the soil is kept cool and moist for optimal growth.
When to Plant Sweet Peas
Sweet peas should be planted in very late winter or very early spring for colder zones, and in late fall for milder climates. They thrive when planted as soon as the soil is workable, without waiting for the last frost date. This timing ensures optimal growth and blooming.
Growing Sweet Peas Outdoors
The best method to grow Sweet Peas outdoors is to plant them in very late winter or very early spring. This method is the easiest because Sweet Peas are hardy and can handle light frosts, allowing them to establish before the heat of summer. Here’s a step-by-step guide for home gardeners:
- Choose the right time. Plant in very late winter or very early spring in colder zones. In mild winter climates, plant in late fall.
- Prepare the soil. Select a well-drained site with alkaline soil. Mix in compost or well-rotted manure to a depth of 2 feet.
- Soak the seeds. Soak seeds for 24 hours before planting to speed up germination.
- Nick the seeds. Lightly score the outer shell of the seeds with a nail file to aid sprouting.
- Dig a trench. Create a 4-inch deep trench for planting the seeds.
- Plant the seeds. Place the seeds in the trench and cover them with soil. Firm the soil gently.
- Water the soil. Keep the soil moist but not waterlogged. Use mulch to retain moisture.
- Provide supports. Use trellises or bamboo poles for the plants to climb. Tie the initial stems to the supports.
- Pinch off tops. When plants reach 6 inches tall, pinch off the tops to encourage bushier growth.
- Pick flowers often. Regularly pick flowers to encourage more blooms and prevent the plants from going to seed.
Growing Sweet Peas Indoors
Growing Sweet Peas indoors is possible and can be a delightful project for home gardeners. Here’s a step-by-step guide to help you get started:
- Soak seeds overnight. This softens the outer coating and aids germination.
- Sow seeds half an inch deep. Use individual cells of a seed tray for best results.
- Transplant seedlings into larger pots. Do this once they show their first leaves.
- Harden off seedlings. Place them in an unheated greenhouse or a sheltered outdoor spot for a few days.
- Plant outside as soon as the soil can be worked. Ensure the soil is well-drained and enriched with compost or well-rotted manure.
Sweet Peas are known for their delightful fragrance, but did you know that they can also attract beneficial insects like bees and butterflies to your garden? This not only enhances pollination but also contributes to a healthier garden ecosystem.
Caring for Sweet Peas
- Keep the soil moist: Sweet Peas thrive in consistently moist soil, especially during dry periods. Regular watering is essential to keep the plants healthy and blooming.
- Use high potash feeds: If your Sweet Peas need a nutrient boost, opt for high potash feeds. This type of fertilizer encourages more flowers and stronger growth.
- Mulch well: Applying mulch around the base of the plants helps retain moisture and keeps the soil cool. This is particularly beneficial during hot weather.
- Watch out for pests: Common pests like slugs, snails, whiteflies, and aphids can affect Sweet Peas. Use horticultural oils or chemical pesticides to manage these pests effectively.
- Pick flowers often: Regularly harvesting the flowers not only provides beautiful bouquets but also encourages the plants to produce more blooms. This practice prevents the plants from going to seed too early.
Common Challenges With Sweet Peas
Sweet Peas are often considered a resilient plant, capable of handling light frosts and thriving in well-prepared soil with adequate nutrients and moisture. They are relatively easy to grow from large, easy-to-handle seeds, making them a favorite among gardeners. However, they do require some patience and care, especially during the germination phase, which can be slow and unpredictable.
Common challenges when growing Sweet Peas include their susceptibility to pests like slugs and snails, as well as fungal diseases such as root rot and powdery mildew. Additionally, they need proper support structures for climbing varieties and consistent moisture to prevent the soil from drying out. Despite these challenges, with the right care, Sweet Peas can be a rewarding addition to any garden.
Safety of Sweet Peas for Pets
Sweet Peas are toxic to pets, including cats, dogs, and other animals. If you suspect your pet has ingested Sweet Peas, contact the ASPCA 24-hour hotline immediately for assistance.
Frequently Asked Questions
Do sweet peas reseed? Can they become invasive?
Sweet peas can reseed themselves if the pods are left to mature and drop seeds. However, they are not typically invasive. Regularly picking flowers and removing seed pods can prevent unwanted spreading and ensure continuous blooming.
What about deer? I have many deer where I live.
Sweet peas are generally not a favorite of deer, but in times of scarcity, deer may nibble on them. Using deer repellents or protective netting can help safeguard your plants from potential damage.
Are sweet peas contributing to my tomato problem?
Sweet peas and tomatoes do not share common pests or diseases, so it is unlikely that sweet peas are affecting your tomatoes. Ensure both plants have proper spacing and care to thrive independently.
Can I rejuvenate a sweet pea shrub?
Yes, you can rejuvenate a sparse and leggy sweet pea shrub by cutting back the stems to about 10 inches long. Remove the thickest, woodiest stems entirely. This will encourage dense new growth and more abundant flowering the following season.
