One of the best plants for cutting, sweet peas (officially known as Lathyrus odoratus) offer tempting colors and aroma for spring and early summer bouquets. The tiny flowers emit a grape-like fragrance into the air and come in a variety of beautiful colors. We enlisted the assistance of Barb Pierson, our nursery manager, to provide some guidance for individuals who have never grown Sweet Peas in a garden or a container pot. Any beginner or green thumb can benefit from a plentiful supply of these lovely flowers thanks to her advice.
Why do people grow Sweet Peas?
Sweet peas are cultivated for their lovely, ruffled blossoms, which come in pastel, blue, and bicolor hues. They are a beautiful cut flower since many types have scented blooms. The cultivation and breeding of sweet peas for both the home grower and the florist industry has a long history.
How do I go about growing Sweet Peas?
Sweet peas can be grown from seed that is treated before sowing or, more conveniently, from a starting plant. At White Flower Farm, we plant three seeds in each pot to create three Sweet Pea vines.
Where do I plant them and when?
In the northern half of the US, sweet peas flourish in the full sun. They can benefit from afternoon shade in the South. They are planted as early as possible in the spring since they prefer mild temperatures and cool roots. Newly planted seedlings will not be harmed by a mild cold. They can be sown in the fall and cultivated through the winter and early spring in highly warm climates. Compost should be added to the soil, and the area should be well-drained for optimal results. Sweet peas can be successfully grown in raised beds.
Do they need any special care while they are growing?
Sweet peas require support to grow and flower because they are climbing plants. Many other kinds of structures, like a trellis, supports made of mesh or wire, or fences, can be used. To sustain the weight of the vines, they require a sturdy framework that is firmly planted in the ground. The vegetation will develop tendrils that encircle the support you offer.
Since they like nutrient-rich soil, adding compost at planting time is advised. Mulching Sweet Peas will keep the roots cool and help them retain moisture as they grow.
Pinch the growth tips by one after the plants have reached a height of around six to encourage branching and the development of extra flowering stems.
What are the most common mistakes that people make with Sweet Peas?
- planting them in the middle of the summer They dislike the heat and won’t blossom as frequently.
- not offering assistance when planting. Once the plants have begun to grow, it is challenging to install your trellis or support.
- Lack of compost or fertilizer will cause weak plants and fewer flowers in poor soil.
- If Sweet Peas are planted too closely together without being thinned out, powdery mildew can grow and crowding lowers bloom production.
Do Sweet Peas produce pods that you can eat like the ones you find in the grocery store?
Despite having the appearance of snap pea pods, the seed pods are not edible. The pods and seeds can be saved in order to grow plants the following year. Remember that the plants that the seeds may grow may not be the same hue as the parent plant.
Will the plants come back again next year?
The plants are typically not winter hardy in most areas. They are replanted with new seed and plants even in warm climates to produce the most flowers and have robust development.
When do they bloom? Are there tips for getting extra blossoms?
Sweet peas will begin to blossom 4 to 6 weeks after they begin to show apparent vining. Whether or not the plants have been pulled back will affect the timing of the bloom. Although pinching may slightly limit growth, it will result in bushier plants with more flowers. In the spring and early summer, sweet peas will grow and bloom more quickly as the days lengthen. Compost or old dry manure can aid to supply nutrients for the growth of huge, many blooms. A fertilizer with a phosphorus to nitrogen ratio greater than one can also increase flower production.
What is the process for cutting the blooms?
Cut the blossoms early in the day to prevent the sun from drying them off. For your vase, select newly opened flowers with the longest stems. Just the side flowering stems of the plant should be clipped; leave the main stem alone.
Why should I get my Sweet Peas from White Flower Farm?
No seed treatment or waiting for germination is necessary because our plants are grown in our greenhouses in the spring and supplied to you at the ideal time for planting in your region. Our sweet peas arrive completely rooted and ready to plant in the ground in 4 pots, each containing 3 seedlings. You can avoid the time and hassle of starting sweet peas from seed by doing this. The quickest method to enjoy these beautiful flowers outdoors and in vases within your house is to purchase and plant our Sweet Pea seedlings.
How can I hasten the growth of my peas?
In optimum conditions, pea plants grow the fastest. If at all possible, plant peas in raised beds since the soil in the raised bed will be warmer in the spring than the surrounding soil. Peas grow more quickly in warm soil. Give the pea plants robust support; a trellis or fence will enable the plants to grow quickly and vigorously. Mulch promotes faster plant growth by keeping the soil cold and moist around the shallow roots of the plants. By dusting legume inoculant over the pea seeds before to planting, you can increase the productivity of the pea plants. Rhizobia bacteria included in commercially available inoculants assist the pea plant in fixing nitrogen in the soil.
What is causing my sweet peas to grow so slowly?
This is a typical issue that many gardeners lament. Sweet pea blooms may begin to wilt at any time. When the buds fall to the ground, they occasionally haven’t even opened. Even worse than not having any blossoms at all is that.
Consider the weather conditions in the area of the potted plant before attributing it to a hidden illness or a fungal infection. In particular, keep an eye on the room’s nighttime temperature to make sure it doesn’t fall below 30 degrees F. The plants may experience great stress and lose their buds if the temperature drops suddenly.
The incorrect fertilizer can also cause a growth spike that the plant cannot sustain, making the buds brittle and prone to breaking in the smallest breezes.
How to Fix it
The fading of blooms and buds is brought on by a number of reasons. Stress is the most prevalent one. Because they are delicate plants, sweet peas are susceptible to drought and temperature changes. Use the advice below to make sure your sweet pea blooms successfully finish their whole life cycle.
- Put a 2-inch layer of mulch on top of the soil in the pot if it dries out too quickly. It will increase soil water retention and shield the plant from drought.
- Sprinkle the sweet peas with cold water when the mornings are warm and the evenings are chilly. The shock of abrupt weather changes will be lessened as a result.
- Use organic manure and compost as fertilizers rather than synthetic ones. In this manner, you can avoid overstressing the plant and maintain a low amount of nitrogen in the soil.
- Remove old blooms and seed pods from the plant to encourage the development of fresh, healthy buds.
How come my sweet peas won’t grow?
It’s possible that your plants aren’t getting enough light if they aren’t blossoming (they need a minimum of 8 to 10 hours a day, but preferably nearer to 16 hours). You should move them to a sunny location if the place where they are planted is too shaded, but be sure to do it on a coolish day and water them thoroughly to help them settle. Too much nitrogen in the fertilizer can also occasionally lead to tall, green plants without any blooms. Feed the sweet peas either a high phosphorous feed or some bone meal to get around this.
Which fertilizer is ideal for peas?
Fertilizers with a high phosphorus and potassium content but a low nitrogen content are ideal for pea plants. The numbers on fertilizer packages are very important. The percentage of each of these important nutrients is indicated by the three digits on the container.
- Low-nitrogen, high-phosphorus, high-potassium fertilizers, like 5-10-10, are preferred by peas.
- The “5” in 5-10-10 fertilizer denotes that it contains 5% nitrogen.
- The first “10” in 5-10-10 denotes that the fertilizer contains 10% phosphorus.
- The second “10” in 5-10-10 denotes the fertilizer’s 10% potassium content.
No matter what variety of pea you are producing, stay away from fertilizers with a high nitrogen content. Excess nitrogen will make your pea plant grow a lot of leaves and stems, but will cause it to produce fewer pea pods.
What promotes pea growth?
- Plant seeds about 2 inches apart, 1 inch deep (or a little deeper if the soil is dry). Never thin.
- Plant rows with a 7-inch spacing.
- Peas should not be planted in the same spot more frequently than once every four years as part of crop rotation.
- Like other legume roots, pea roots fix nitrogen in the ground, releasing it for use by other plants.
- Peas require phosphate and potassium in their fertilizer, but too much nitrogen will favor the growth of foliage rather than blooms or pods. Study up on soil amendments.
Bush peas can grow to a height of 18 to 30 inches. Pole types can reach heights of at least 4 to 6 feet. Support is beneficial for both types (especially bush peas above 2 feet and all pole peas). Before plants develop their shallow roots, install thin tree branches or twiggy sticks (pea sticks), trellises, chicken wire, strings, or netting. See the building guidelines for pea trellises and supports.
Keep the soil moist by watering. Put seeds back into the soil if they wash out.
- Pea plants shouldn’t receive more than an inch of water every week unless they are wilting. Not wanting to promote pea rot is our goal. Don’t let the plants to dry out, though. No pods will grow if this takes place.
Hand-pull invasive weeds with care. If hoeing or cultivating is required, do so very cautiously to prevent upsetting the peas’ shallow, delicate roots.
There are various causes causing pea leaf yellowing. This frequently results from the strain of hot temperatures. During the hottest portion of the day, offer some shade (such as row coverings) and provide adequate watering.
If plants are mulched extensively with grass clippings, crushed leaves, or another biodegradable material, fertilizing is typically not necessary.
The most popular kind of peas are known as shelling peas, sometimes referred to as garden or sweet peas. You should try the following varieties:
- “Green Arrow” is a 2- to 3-foot vine with great yields, little need for support, and resistance to mildew and Fusarium wilt.
- “Lincoln” is a 2- to 3-foot vine that requires no support and is resistant to mildew and Fusarium wilt.
- The iconic “Wando” (good for freezing)
- In “Thomas Laxton” (high sugar content)
- the ninth progress (good disease resistance)
- In “Little Marvel” (grows only 15 inches tall)
Snap peas: The entire soft pod of snap peas is consumed. There are a few good kinds to try:
- “Sugar Ann” vines only reach a height of 2 feet and don’t need a support.
- “Sugar Snap”: The original (Calvin’s) has recently been reintroduced. only available through Johnny’s Selected Seeds.
- Early Snap: A pea variety that matures 10 to 14 days earlier than Sugar Snap.
- The plant ‘Super Sugar Mel’ yields 4-inch-long, extremely delicious pods.
Snow peas: These flat-poded peas have edible pods and are frequently used in Chinese cuisine. You should try the following varieties:
How frequently should sweet peas be watered?
If you pinch out the growth point while immature sweet peas are in the seedling stage, whether you sow them in the spring or the fall, they will sprout more branches that will bear blossoms.
I examine sweet pea maintenance in the video, focusing on how to remove the growth point. The video demonstrates how to reduce the sweet pea’s growth point to encourage it to produce more shoots, which will increase the number of summer flowering stems.
The following photos:
- The young sweet peas in the first photograph already have a few early leaves.
- Secateurs to indicate the location of the growth point removal.
- The full tray of seedlings with each seedling’s top growth point removed can be seen in the center image.
- The single stem is no longer present in the third photograph, which was shot about 10–14 days later, and there is now a side branch.
Once planted, they require constant watering if the summer is dry since sweet peas detest being dry because it makes them susceptible to mildew.
It’s also important to get rid of any tendrils in order to keep them straight and attractive.
It takes an hour or more once or twice a week at the height of summer to grow the 50 or so plants that make up a beautiful display, which makes for heavy upkeep.
Choosing sweet peas and perennial peas
The major consideration is whether or not aroma is crucial to you when deciding between perennial Lathyrus and sweet peas. Decide if you would then like an annual or perennial plant. There are several color choices available as well as climbing and bushier varieties.
Fragrance
Choose sweet peas (Lathyrus odoratus), which are generally very fragrant, if you enjoy a pleasant garden and sweet-smelling flowers for indoor use.
Lord Anson’s blue pea (Lathyrus nervosus), a perennial Lathyus, is an exception to the rule since it does have a perfume.
How long the plant lasts
After setting seed, sweet peas (Lathyrus odoratus) only have a one-year lifespan. However, don’t let this deter you because they are quite simple to grow from seed. Lathyrus latifolius is an example of a perennial species that returns every year, however there are fewer options and they typically lack smell.
Colour
The annual sweet pea (Lathyrus odoratus) has a large variety of blossom colors, including bicolored varieties. However, the perennial varieties do come in some uncommon colors, like yellow and orange.
Habit
The majority of Lathyrus are climbing plants, therefore support them with canes, netting, or allow them to climb over a bank or through a bush. For ground cover and pots, clumping varieties like the spring-flowering Lathyrus vernus and dwarf bushy sweet pea varieties like “Snoopea” and “Bijou Mixed” are excellent choices.
Buying sweet peas and perennial peas
Although many garden centers also sell a few sweet pea seeds in packets, the largest assortment of sweet pea seeds may be acquired from internet seed suppliers. In the spring, several nurseries and garden centers sell pots of germinated sweet pea seedlings that can be divided into individual plants and raised in pots before being planted outside.
There are a few seed specialists who sell perennial Lathyrus seeds, like Lathyrus latifolius, but many gardeners opt to purchase the plants instead. The plant you’re looking for can be found using our Find a Plant tool.
When to plant sweet peas and perennial peas
- Annual sweet peas should be sown either in late January or early April and planted out in April.
- Sow perennial Lathyrus in the spring or the fall.
Where to plant sweet peas and perennial peas
Locate a sunny area where there is room for the plant to grow or to bush out (depending on its habit). Also acceptable is a little light shade, especially for Lathyrus grandiflorus.
How to plant sweet peas and perennial peas
- To avoid cold shock, indoor seedlings should be hardened off for 10–14 days before being transplanted outside.
- Ideally, four weeks before planting, enhance the soil by incorporating a soil conditioner like garden compost or manure.
- Sprinkle general-purpose fertilizer, as directed on the pack, into the area where you plan to plant it, such as Growmore, Vitax Q4, or blood, fish, and bones.
- Before planting, water your plants thoroughly to hydrate the roots.
- Remove pots from larger plants and ease seedlings out of modules or pots while being careful not to snap or crush the stems.
- Plants should be separated by 20–30 cm (8–1 ft).
- Place climbing plants near to their intended support (within 5-7.5cm or 2-3in), with two plants at the foot of each cane if they are climbing a wigwam.
- After planting, water once more to help the soil surrounding the roots settle.
Use garden twine or sweet pea support rings to secure young climbing plant shoots to canes, pea sticks, netting, trellis, or shrub shoots that they will be growing up. Tendrils in contact with supports will naturally start to cling on, but if any are straying or in danger of snapping, keep tying in new shoots.
In dry weather, check on plants in the ground every 3 to 4 days and on those in containers every day because they won’t flower as well if they become too dry. Each time you water, be sure to use enough water to completely moisten the roots.
Apply a high potassium liquid fertilizer, such as tomato feed, once or twice a week on light or infertile soils. This promotes flowering, particularly in annual sweet peas (Lathyrus odoratus).
Pick or remove dead flower heads as frequently as you can once flowering starts. For annual sweet peas (Lathyrus odoratus), which will stop flowering if seedpods are allowed to form, this is especially crucial.
Pinching out
When plants are around 7.5 to 10 cm tall, pinch out the shoot tips of new spring-sown sweet peas for gardening (3-4in). This promotes robust side branching. Autumn-planted seedlings frequently naturally branch.
Cordons
Pick the strongest shoot and keep pinching out all the tendrils and other sideshoots as they grow whether you want to enter your sweet peas in a local show or just want to maximize the size of blossoms for cutting. By using this technique, the plant directs its attention to the blossoms. The term “cordons” is used to describe these single-stemmed plants.
One stem per bamboo cane or tall stake needs to be tied to them on a regular basis. To keep the shoot in place as it grows, you can use twine looped in a figure-eight pattern around the cane and stem. Use sweet pea rings, which are wire loops that wrap around the stem and cane and are lightly squeezed until they hold, to make things simpler.
Cordons have the potential to grow much taller than the typical 2 m (6 1/2 ft) estimated height.
Cutting back
Cut perennial Lathyrus back to the ground in the fall, or better still, wait until February to do it so the dead stems can serve as wintertime cover for wildlife. When flowering is ended at the end of the summer, annual sweet peas can simply be pulled out and composted. This might happen a little bit sooner during hot, dry seasons.
Methods
Sweet peas can be immediately sown into the ground in April, or they can be planted in seed compost pots in the fall or spring. Although it takes more time, pot-sowing is typically more dependable than direct sowing. If you plant in the fall to enhance your chances of getting early blooms, keep seedlings in a coldframe or cold greenhouse over the winter to protect them from growing lanky. Keep the coldframe’s lid elevated unless a strong frost is anticipated. Sweet peas planted in the spring flower in 12–14 weeks.
Sweet pea seeds frequently have a tough outer covering that makes them more challenging to germinate. Place your seeds on a layer of damp vermiculite or kitchen tissue and store them in an airtight container in a warm area. As soon as the seeds swell or start to sprout, plant them. Some gardeners like to soak the seeds overnight instead, but if you don’t plant them right away thereafter, they might rot. With a sharp penknife, chip off a little portion of the hard seed coat to allow moisture to enter and promote germination on recalcitrant seeds that haven’t swelled.
- Individually sow seeds in seed compost-filled rootrainers or 9 cm (3 in) pots. As an alternative, sow five to seven seeds per 13 cm (5 in) pot, spacing them 2-3 cm (3/4-11/4 in) apart.
- Add 1 cm (1/2 in) of vermiculite or compost to the top of the seeds.
- Add water and maintain at around 15C. (59F)
- It is optional to cover the pots with clear polythene or glass to reduce the likelihood that they will dry out, but keep in mind to remove the covering after the seeds have germinated.
- Once they have grown to around 3.5 cm (11/2 in), carefully transplant single seedlings into 9cm (3 in) pots if you have seeded them several to a pot.
- Use your thumb and finger to pinch out (remove) the top of the shoot just above a healthy leaf when the seedlings are 7.5–10cm (3–4in) tall. This will promote side branches, which are always stronger than the core stem that has been removed.
- At least four weeks before planting, remove all weeds from the soil and add a soil enhancer, such as garden compost, manure, or composted bark.
- Only plant seeds as the soil begins to warm, typically around April.
- To create a wigwam, plant any temporary supports, like pea sticks or bamboo canes, in the ground.
- Take out a shallow drill of dirt 2.5 cm (1 in) deep for rows of sweet peas, and plant a seed every 5 to 7.5 cm in it (2-3in)
- Seedlings should eventually be spaced 20–30 cm (8–1 ft) apart to provide the plants enough room to flourish. The extra seedlings may seem like a waste to compost, but unless treated carefully, their roots are typically too damaged to recover.
- Push two seeds into the ground at the base of each cane to a depth of 2.5 cm (1 in) when sowing around a wigwam of canes.