The sweet pea flower (Lathyrus odoratus) is an annual climbing plant from the family Fabaceae (legumes). With origins that can be traced to the Mediterranean and southern Italy, the Aegean Island region, Sicily, and Cyprus.

They exist in varieties and can grow to between 3 and 7 feet as a vine, provided they are supported by arbors, fences or walls.

Most people usually confuse the L. odoratus (annual), with the L. latifolius (perennial).


The first official record on contact with this plant was far back 1695, when a monk and amateur botanist, Francisco Cupani, stated that he saw the plant in northwestern Sicily.

Fascinated by the plant, the monk sent some seedlings off to botanists in England and Holland, where a formal article was documented about the flower. The article contained the first known description of L. odoratus. Due to his encounter with the plant, the name ‘Cupani’ till this day remains a popular variety of the plant.

The sweet pea flower is often considered to be old fashioned due to its long history. However, many are still of the impression that it is still a lovely flower to have around the garden.


Sweet peas are mostly grown from seeds which were collected from the matured ones the previous year.

They are cool-weathered plants, meaning they thrive best under cool temperatures. For quality growth, they’ll need about 50 days of cool temperatures from the period of planting to blooming. Soil temperatures the seedlings can grow under ranges between 55 to 65°F.

They are cool-weather plants and can take frost without significant damage, but can be killed by hard freezes.

The best time to grow L. odoratus seeds especially for gardeners in the western United States, is from August.

For states with drier climates such as Midwest, and northeast non-coastal areas, it is advisable to start seeds indoors to transplant when the climate is cool enough. 

Gardeners in the south can plant in November or December. 

There’s a trick many gardeners use to have better germination rates by gently nicking the seeds with nail clippers. In the event you are starting seeds indoors, ensure that you use a quality potting mix in small pots.

Check the back of your seed packet to know the depth suitable for planting as different depths is recommended for different cultivars.

The planting pots should be placed under sunlight, sufficiently watered taking into consideration a good drainage.


When your pot seeds begin to grow three or four pairs of leaves, then it’s time to take them out. At this stage, move your pots outside to a spot that gets direct morning sun and afternoon shade.

Then wait for another four days in which you’ll move them to another place they’ll get direct sunlight all day. Wait till another four or five days before finally transplanting the peas to your garden.

Ensure that the location for transplanting gets enough sunlight and prepare the soil by adding compost and turning the entire patch. This is done to enable the flower to grow stronger and deeper roots while feeding on a rich soil.

As mentioned earlier, sweet peas are climbing vines, however, you can change that by pinching. Some varieties of sweet peas are more bushy cultivars.

If you are planting climbers which can grow as tall as six feet, place the transplant near a wall, railing, or any kind of support you can adopt.

After placing your plants close to the rail or wall, you can also assist them climb up the railing by adding support rings and curling them through as they grow.

If you aren’t comfortable with using railings or support, you can allow them to grow uncontrolled forming a ground cover.

They need to be spaced out at least six inches apart so as to allow for proper air circulation and also ensure their roots don’t get tangled as a result of being crowded together. 

When transplanting from pots, ensure that the holes in which you are planting into is the depth as planted in the pot.

If you are planting directly outdoors, place one or two seeds per hole, and remember to space them six inches apart.


If you prefer a more bushy shape, but do not want to grow a bushy cultivar, you can as well grow them into such form by pinching.

To do this, pinch off the stem tip and newly grown leaves above the matured set of leaves, using clean shears or the tip of your fingernails. You should only pinch back the plants when they have been established.

You can continue to pinch back the plants all through the season when the vines start growing out of proportion.

Planting on a well-nourished and dried out soil will enable the plants grow to seed quickly.



Cut off faded flowers and emerging seed pods so as to prolong blooming and slow down the seedling process.

You can also prolong the blooming season by applying fertilizer to the plant regularly. Fertilizer mixed with compost will help nourish and keep the soil moist, helping them to grow strong roots and flowering.

Applying fertilizer to the plant should be done once or twice in the growing season. Use fertilizers rich in potash feed, or use compost tea.


There are a wide variety of L. odoratus cultivars you can choose from:

Royal Family Mix

The ‘Royal Family Mix’ is just the right plant for those who like a fancy mix of colors. It can grow to about 5 to 6 foot vines, and is available in various quantities.

High Scent

For fragrance lovers, consider growing the ‘High Scent’ flower from Burpee. They grow large white blooms edged in the lavender.

Cupani Sweet Pea Seeds

You can purchase them from Nuts n’ Conesvia Amazon.

Little Sweetheart Sweet Pea Seeds

If you prefer planting in pots, or do not have enough space to spread them around. You can purchase them from Hirts va Amazon.



Sweet peas are plagued by aphids, caterpillars and cutworms. For aphids, they can be blasted off with a stream of water, while sprinkling diatomaceous earth around the base of your plants will keep caterpillars and cutworms away from your plant.

For leafminers or thrips, use traps. Try neem oil for spiders.

Snails and slugs are another enemy, however, they do not pose too much of a big deal as they can be treated with a bait. Consider Sluggo available on Amazon.


Plants will only be vulnerable to diseases when they are packed or crowded together, or where they don’t receive enough sunlight. Mildew can also be a cause of plant diseases.

To control plant diseases, ensure to regularly thin the plants, or better still apply a fungicide.


Sweet peas are climber plants, therefore you can decide to let them crawl against the wall like a wall covering.

You can grow it in a pot and let it trail over the sides.


As much as some people find the L. odoratus old fashioned, the fact that it has been around for ages and still relevant is something to respect. Just provide the plant with cool weather, adequate sunlight, and moderate watering, and expect to see nice showy flowers in your garden.

Have you grown this lovely flower in your garden? Share your experiences with us!

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