One of the most romantic of all flowers is surely the sweet pea (Lathyrus odoratus), with its frilly, butterfly-like blooms and heady fragrance, likened to honey and orange blossoms.
Native to the eastern Mediterranean region, it has been in cultivation since the 1600s when, according to legend, a Sicilian monk named Franciscus Cupani took note of its qualities and sent seeds to England. But it wasn’t until the late 1800s that a Scottish nurseryman, Henry Eckford, recognized the sweet pea’s potential and developed numerous varieties (some still on the market), launching this humble member of the Pea Family into garden stardom.
Now sweet peas come in every color except true yellow, from red to lavender to navy blue, some streaked and flecked. Most types trail for six to nine feet or so, but there are also shorter forms ideal for containers that are only eight to 20 inches tall.
While the sweet pea is considered an annual, there are a few perennial cultivars, but they lack fragrance. As does a related perennial species, the everlasting pea (Lathyrus latifolius). Since some breeding of sweet peas has actually favored blossom size over scent, be sure the ones you’re buying are scented if that’s an important factor to you.
Relatively easy to grow, the main thing to remember is that sweet peas like cool weather, requiring about 50 days of temperatures under 60 degrees to bloom well. In cooler climates, sow seeds outdoors in early spring as soon as the soil is workable. Seedlings can withstand a touch of frost, so don’t stress if the weather turns colder. Flowering will last from spring into summer, and even into fall in some regions. A thick layer of mulch will keep roots cool and extend the blooming as long as possible.
In the South, sweet peas (look for short-day varieties) can be sown outdoors in the fall, October to early November or even in late winter, January-February. They’ll produce roots but not much top growth until spring.
To speed germination, before sowing make a small nick in the seed coat with a knife, metal file, or sandpaper. This will allow the seed to take up water more easily. Plant seeds one to two inches deep.
You can also start seedlings indoors in a cool place, six to eight weeks before last frost date. But don’t let them entwine together into a tangled mess that’s hard to separate before it’s time to transplant into the garden. Before transplanting, pinch off any flower buds to encourage roots.
The best location offers full sun (except in really hot regions where late afternoon shade will be appreciated), rich soil, and good air circulation. Protect young plants from birds (with netting) and slugs.
Sweet peas will scramble up all manner of fences, trellises, and arbors, attaching themselves by slender tendrils. Supports should be small enough in diameter for the tendrils to easily wrap around. If you want to grow sweet peas up a thick support, you’ll need to attach netting or lengths of twine.
Sweet peas can also be used like clematis to trail through flowering shrubs, to offer wonderful floral combos or to bloom when the shrub is not. Since sweet peas are annuals, they won’t accumulate a mass of vines from year to year to overwhelm their shrub “host.” They can also be grown alongside perennial or woody vines to extend the season of interest.
Though not edible like their garden-pea cousins, when trained up bean teepees in the vegetable garden sweet peas add an element of beauty and also attract beneficial pollinators like bees, which will then visit your fruit and veggie plants.
Another benefit of growing sweet peas is they make excellent, long-lasting cut flowers. A clutch of them in a small vase brings their heavenly scent and the romance of the cottage garden indoors. And by regularly cutting flowers from the plant, you’ll be encouraging more blooms.