When to Plant: Sweet peas can withstand light frosts, therefore in cold winter regions, sow in seed starting pots in early spring approximately 6-7 weeks before the final day of frost. Then, plant out as soon as the soil can be handled.
Sweet pea seeds can be directly placed into the garden in the fall from September to November in mild winter settings where the ground does not freeze. This will allow the seeds to develop healthy root systems and bloom in the spring.
If you give your seeds a head start by sowing indoors in seed containers from late January through March and transplant into the garden as soon as the soil can be worked, you can still receive a decent harvest of sweet peas, even though they will bloom a bit later. Sweet peas can handle light frosts.
1. Before planting, you could decide to nick your sweet pea seeds. The seed’s outer layer can be broken off by giving it a quick cut with a nail clipper so it can quickly absorb water. This will result in a higher percentage of your seeds germinating and a few days earlier sprouting.
This is how: Between your thumb and forefinger, hold a seed. Clip your seed by holding the clippers at an angle with the other hand so that you can only utilize the tip of the blade. Not taking a chunk out of the seed is your goal; it is to slice through the brown top layer of the seed. Sometimes the nick you caused is barely visible, and other times a bit of the seed coat cracks off revealing the interior seed’s lighter color. Both are true.
2. Avoid using garden soil when planting sweet peas in containers. Use high-quality potting mix instead. Using garden soil can lead to issues like compaction and poor drainage, whereas potting mix recipes are designed to perform under the circumstances found in a small container. In garden centers, a variety of soil mix brands are easily accessible.
Before filling your container, always pre-moisten your potting mix. As you slowly pour water into a bucket or wheelbarrow and stir the dirt, the earth will become evenly moist. When it feels like a wrung-out sponge, you are finished.
A 3 to 4 inch container works well for starting sweet peas. To prevent spreading disease to your new soil mix, properly clean the pot before using it again. After adding the pre-moistened mixture to the pot, give it a quick tap on the work surface to settle the soil. When a pot is filled correctly, the soil surface will be about 1 inch below the container’s top.
3. The time has come to plant your seeds. It matters how deeply you plant them. Always adhere to the planting depth recommendations on your packet’s back. Make a hole that is 1 deep for sweet peas. For this, a pencil or your finger works great.
4. Insert the seed into the opening you created. In order to ensure that every pot eventually gets a plant, even if one seed does not germinate or dies, we advise sowing two seeds each pot.
If you decide to plant 2 seeds per pot, you will need to thin them after the first set of leaves appear to 1 seedling per pot. At the soil line, trim or pinch out any surplus seedlings. Pulling it out could damage the surviving seedling’s roots, so avoid doing so.
5. Cover your seed with soil mixture after sowing. To remember what you planted when and how much of it, we advise labeling your containers with the variety and the date.
6. Lightly mist the seeds you covered. Use a watering can or hose with a diffuser attachment to let the water fall gently like rain. This will stop the water from washing the dirt away or compacting the soil too much.
Create the ideal circumstances for germination as you wait for your seedlings to appear. The two most critical variables are water and temperature. Your soil should always be damp, but not drenched. The ideal soil temperature is between 55 and 70 °F. You can start your seeds outside if the weather permits. A greenhouse or your home must be used to start them otherwise. Provide protection from birds, snails, and slugs if beginning them outside.
You must give your seeds a decent source of light once they have sprouted. If you want to keep them inside, you can put them beside a window as long as the sun won’t make them too hot during the day. Sweet peas do not have an issue with cooler nighttime temperatures near a window. Another option is fluorescent lighting. However, for the intensity to be bright enough, plants should be placed between 6 and 12 inches from the lights.
7. If you started your seeds indoors, the seedlings must be hardened off before being transplanted into your garden. Hardening off is the process of gradually exposing your plants to the elements they will experience outside, with temperature and direct sunlight being the most important factors. If you don’t, your seedlings can have transplant shock once they are planted in the garden.
When your plants have around 3–4 pairs of leaves, you can begin the hardening off procedure. Place your plants outside where they will receive morning sun in full force and afternoon shade. If you don’t have access to such a place, you will need to relocate your plants every day so that they are in the morning sun and out of the afternoon sun. Move them to a location where they will receive direct sun all day after about 3–4 days. You can move them into your garden in a few more days.
8. You can pinch or chop off the top of your seedlings when they have 3–4 pairs of leaves, leaving 2-3 pairs of leaves. Your cut should be made just above two leaves. By encouraging lateral branching, pinching helps you grow plants that are fuller.
9. Since sweet peas require healthy, well-drained soil, add some aged manure or other finished compost into your garden bed before planting. Work the material into the soil and rake the bed to level it out.
To move your seedling, make a hole that is both deep and wide enough to accommodate the root ball.
10. Try to minimize root disturbance while transferring your sweet pea seedlings from their container. Try it. Put one hand over the top of the pot, the seedling in your fingers, and flip the pot over to grab the root ball. Using the other hand, gently touch the bottom of the container while squeezing the edges to release the soil and plant.
11. Insert your seedling into the resulting hole, then cover it with soil. It is crucial when transplanting sweet peas that the soil level remain the same as it was in the pot. The plants may become sickly, stunted, or even die if you bury too much of the stem.
12. Leave 5 to 6 feet between each transplant. Your mature sweet peas’ health depends on the proper spacing between plants. Additionally, it provides the roots of individual plants with enough room to forage for water and nutrients while also enhancing air circulation to help avoid disease.
13. Gently water in your seedlings as soon as you are done transplanting. In addition to giving the plant water, this settles the garden soil around the root ball to prevent huge air pockets from drying out the roots. Use a watering can or hose with a diffuser attachment to water your plants, which will make the water fall gently like rain instead of washing the dirt away or beating your tender seedlings.
Tall sweet peas require a sturdy support in order to ascend. Build one now so that it is there when your seedlings are prepared to begin climbing.
14. You must keep birds, snails, and slugs away from your sweet pea seedlings. In order to prevent these typical predators from discovering your sprouts and eating them before you even realize they are up, you should do this as soon as possible after sowing your seed.
Use netting for birds. We create our own support hoops out of polytube, which is a flexible, black plastic irrigation tube that is sold at most reputable garden centers. It should be cut into lengths that correspond to the width of your garden beds. To create arches over your sweet pea bed, bury the ends of the cut tubing in the ground. These arches should be covered with bird netting, which should be secured at all edges to prevent openings. Before your sweet peas grow large enough to attach themselves to the netting, remove it. We choose the product Sluggo for snails and slugs because it is safe for use on people, pets, and wildlife.
15. You might want to assist stray branches in locating their vertical support structure as your plants grow higher and begin to climb. Encourage them to cling to you gently. Branches of sweet peas quickly break.
16. We advise deadheading to prolong the blooming period of your sweet pea plants. This entails removing wasted flowers before they have an opportunity to use their energy to produce seeds rather than other blossoms. Deadheading is best done right when the bloom has peaked and is just starting to fade. Cut the entire flower stem off at all times.
17. The blossoming of this plant is fully complete. When you can see, the plants begin to slow down and eventually stop flowering altogether as the discarded blooms turn into seedpods. Whether you deadhead or not, all sweet pea plants eventually reach the end of their flowering season. However, you can extend the bloom time by removing spent blossoms.
18. The flowers are, of all, the whole reason of producing sweet peas. Don’t forget to frequently clip them and bring them inside. They create lovely bouquets with the most amazing scents. Additionally, the plant will produce more blossoms the more you cut!
spring
- From March to May, you can easily plant your young sweet pea plants outside. Before planting out, sweet pea seeds sown in the winter or autumn need to be potted up into larger containers. Spring-sown seeds can be transplanted from their rootrainers.
summer
- Pick your sweet peas, then put them in indoor vases. Remove the seed pods from your sweet peas to continue deadheading them. You’ll need to harvest and deadhead them frequently when they’re at their height.
How resilient are young sweet pea plants?
According to Gardeners’ World (opens in new tab), sweet peas should be treated like any other non-hardy annual: “Plant your sweet peas outside starting in late May, after all danger of frost has passed. Put them outside throughout the day and bring them inside at night to harden them off before planting.
The most recent edition of Sarah Raven’s podcast (opens in new tab) claims, however, that “Sweet peas are hardy and can go in the garden from the middle of March.”
Confused? So were we up till we learned the RHS’s excellent sweetpea-growing tips (opens in new tab) (watch in the video above). Sweet peas are in fact “extremely tough,” says Propagation Leader Sam Gallivan, and they can withstand frosts “with no issue at all.” They do struggle with extended cold and rainy times, though. Your young sweet pea plants could perish if you reside in a region where early spring can bring both low temperatures just above freezing and a lot of rain.
Because of this, you have two options: either hold off and plant them outside in April when the weather will be warmer, even if it rains, or keep them in a cold frame until the chilly showers stop. However, sweet peas are typically categorized as half-hardy annuals and can withstand dry frost up to -4C. (25F). You will need to cover them with horticultural fleece in the event that temps fall below that.
What degree of cold can sweet pea seedlings endure?
As annual plants, sweet peas (Lathryus odoratus) complete their whole life cycle in a single growing season. This traditional flower germinates well in cool environments, but if the plants are not covered, frost and freezing temperatures can cause damage to sweet peas. Direct sow sweet peas outdoors in late fall in warmer areas to enhance winter and spring blooms. Young seedlings can survive cold snaps if they are shielded from abnormally low temperatures.
Tip
Sweet peas can withstand a slight frost, but immature seedlings can freeze in temperatures below 25 degrees Fahrenheit. To ensure your cutting garden flowers will endure chilly nights in the early spring, protect sweet peas when low temperatures are anticipated.
Which month is ideal for planting peas?
Nothing compares to the delightful flavor of peas straight from the garden in terms of sweetness. They are fresh candies from nature! One of the earliest crops of the year, peas are planted as soon as the land can be worked, even if snow follows. See our growing advice for peas, from planting to harvesting!
About Peas
Peas are incredibly simple to raise, however they only have a very short growing season. It’s crucial to plant them in the springtime early enough for them to mature while the temperature is still cool. (This refers to planting in most of the United States and Canada in February, March, or April.) In warmer areas, they can also be cultivated as an autumn or winter crop.
Enjoy the flavor of peas as soon as you can because they don’t keep fresh for very long after harvest. The taste of the peas you get in grocery shops, which are frequently starchy, is incomparable to garden-fresh peas.
Most garden and culinary requirements can be met by three types of peas:
- The seeds (peas) of sweet peas, also known as garden peas or English peas (Pisum sativum ssp. sativum), are extracted from inedible pods.