The woven-wire fence surrounding our garden by the back alley of my boyhood home in Lisbon, N.D. always bloomed abundantly with sweet pea flowers. Have you smelled sweet peas? They’re one of life’s greatest simple pleasures, and a bouquet in a glass of water is simple beauty at its fragrant finest.
Mom always planted sweet peas, which grow as an annual vine, needing woven fencing, trellis, or lattice for support. I’m not sure where Mom and all the other old-time gardeners learned to do what they did, but I suppose techniques were passed along word-of-mouth, and learn-by-doing experience took care of the rest. Sweet peas were a favorite vining flower of our grandparents and great-grandparents, and as cycles go, the old-fashioned favorite is making a comeback. Probably because trellises and lattice screens are popular privacy items in the landscape, and sweet peas are a perfect vine to add.
Planting sweet peas isn’t difficult, but as the old-timers learned, there are techniques that improve success, and these methods are just as important today.
Growing Sweet Peas:
- Packaged seed can be found on most seed racks, or through mail-order companies.
- Varieties vary greatly in fragrance. Between the old-days and the present, breeders developed larger blossoms, often at the expense of fragrance. Older, more aromatic types had smaller flowers. Breeders continue to work diligently to combine large flowers with full fragrance. There are many sweet pea varieties on the market. When buying, look at descriptions carefully and choose those that distinctly say they have peak fragrance. If they don’t mention fragrance, the aroma is probably less distinct.
- Sweet pea seed can be started early indoors, but the old-timers, my mother included, planted them directly outdoors. They aren’t the most receptive plants to having their roots disturbed in transplanting, so I favor direct planting. Plus it saves work.
- Sweet peas are a cool-loving flower, and will tolerate frost. They are best planted in very early spring, as soon as the soil is workable. Mom always planted them in April in North Dakota. This will vary by season, but April 1-15 works fine, or April 15-30 if spring arrives later.
- Sweet pea seed is very hard. Although some recommend nicking each seed with a nail clipper or file, it’s easier to just soak them overnight in lukewarm water, my Mom’s practice, that I’ve found successful as well.
- Sweet peas like cool soil. To keep the roots in the cool-soil zone, plant the seeds in the bottom of a 6-inch deep trench, covering each seed with one inch of soil. Space seeds about 2 inches apart. As the seeds sprout, and the plants grow, gradually fill in the trench with soil.
- Plant seeds fairly close to the bottom of the fence or trellis, within an inch or two. Sweep pea vines twine and cling with tendrils, so they don’t need our help in attachment. To grow sweet peas on a solid board fence, attach wire mesh or chicken wire.
- Sweet peas like cool, moist soil. Add 3 inches of mulch over the soil and around plants. Dried grass clippings, straw, shredded bark or compost work fine. Other annuals like marigold can be planted later to shade the base of the sweet pea vines. Sweet peas are one of the plants that “Likes their head in the sun and their feet in the shade.”
- Don’t let soil become hot and hard-baked in the heat of summer, or sweet peas will diminish quickly.
- Keep flowers picked to extend the blooming season.
- Later in the season, flowers can be left to form seed pods, if you’d like to collect your own seed for the following year.
- Powdery mildew disease can be a common problem, causing gray-white coating leading to drying and death of foliage. Don’t water vines overhead, avoid wetting foliage by watering only the base of plants, and apply fungicides as preventatives, if desired, at the very earliest sign of the disease.