It’s no wonder age-old sweet peas are still a favorite Southern floral.
Some gardeners think they smell like orange blossoms, honey, and jasmine.
Others say they have a grape-like scent.
Credit: Michael Boys/Corbis/VCG / Getty Images
Sweet peas aredeer-resistant, but butterflies and bees love them.
you might differentiate between the two becauseL.
latifoliusdoes not have the sweet scent.
Elsewhere, plant them fromlate winterto very early spring.
Plants are available for a very short window, so most gardeners plant seeds directly in the garden.
Light
Sweet pea flowers thrive in full sunlight.
Soil
Sweet peas need deep, well-draining, humus-rich soil with a neutral to alkaline pH.
For best results, amend the soil with compost in the fall or at least a week before planting.
Mulch around the base of plants to keep the soil moist and cool.
Water
Water regularly if rainfall isn’t sufficient.
Keep the soil lightly moist during the growing season.
Check the top inch of soil with your fingers and water if dry.
While the seedlings tolerate light frosts, heavy frosts can damage the foliage.
Gardeners in cooler regions may enjoy flowers until mid-summer or even later.
Deadhead sweet pea flowers often and remove dead or diseased leaves and pea pods.
Sweet pea vines die naturally when the temperatures rise.
Propagating Sweet Peas
Sweet peas can easily be propagated from cuttings in water or soil.
For best results, take cuttings early before temperatures rise too much.
Use young sweet pea seedlings, but wait until they have started to develop side shoots before taking cuttings.
Some seeds can take a long time to germinate, but two to three weeks is typical.
Soak them overnight in water to soften their hard seed coats for better germination.
Seeds that do not swell from the soaking will have a better chance if you nick the seed coating.
Then plant two or three seeds per pot in biodegradable pots of fresh potting mix.
Pinch the growing tips when the seedlings are about 4 inches tall, so they’ll form side shoots.
Plant them in rows, 6 to 8 inches apart, in full or partial sun.
You should see blooms four to six weeks after the vines start growing.
Potting Sweet Peas
Whengrown in containers, sweet peas need something to climb like a small trellis.
Pinch the seedlings' growing tips when they’re 4 inches tall.
Overwintering
While sweet peas are relatively cold-hardy, there are ways to protect plants during the winter.
Move sweet peas indoors when temperatures drop below freezing when planted in containers.
To help protect the plant’s roots, cover them with burlap.
Protective netting or wire baskets can help keep pests away until the seedlings emerge.
Pests like aphids, leaf miners, spider mites, and thrips can attack sweet peas.
Slugs and snails also pose a risk to sweet peas.
Try knocking off pests with a strong stream of water from your hose.
Keep sweet peas weeded so pests can’t hide nearby.
When needed, spray with insecticidal soap or neem oil to eliminate pests.
Use snail or slug baits or traps.
Remove heavily infested or diseased foliage to keep problems from spreading.
If diseases persist, look for a fungicide labeled for your specific problem.
Deadheading will encourage the plants to keep producing flowers.
To help increase the flower’s bloom size and longevity, use compost or dried aged manure.
Fertilizers with higher phosphorus than nitrogen will also improve flower production.
Sweet peas bloom best infull sun.
Here are a few problems you may run into when growing sweet peas.
Water as needed to keep the soil moist.
Cut off buds that threaten to drop at the base of their stems so the plants can keep growing.
Overfertilizing can also cause bud drop.
Stop feeding until the flowers open entirely.
Not Enough Buds
Too much nitrogen can promote leaves instead of flowers.
Switch to a tomato fertilizer if your product seems to result in more green growth than blooms.
Yellow Leaves
Leaves can turn yellow from overwatering or overly heavy soil.
Keep the soil lightly moist and improve drainage if possible.
This problem can also happen if compost is not mature enough and ends up burning the roots.
When sweet peas grow leggy and a pale yellowish-green, this is a sign of insufficient light.
Move your container or prune surrounding plants if possible to increase sun exposure.
Crispy Leaves
Sweet pea leaves will bleach and turn crisp when scorched by heat and sun.
Increasing watering or providing some afternoon shade with screening could help.
Crispy leaves can also indicate your plant is at the end of its life.
Frequently Asked Questions
Sweet peas have a deep root system that doesn’t like to be disturbed.
Don’t plant onions or potatoes or deep-rooted perennials next to sweet peas.
However, if you allow your plants to set seed, new seedlings may emerge the following year.
American Society for the Prevention of Cruelty to Animals.Sweet pea.
North Carolina Cooperative Extension.Lathyrus odoratus.
