Sweet peas are the ultimate “instant gratification” climbers. Seriously, as soon as these beauties hit your garden soil, they start racing toward the sky. But while that lightning-fast growth is a huge plus, it also means you’ve got to stay on your toes to keep up with them!
The One-Season Wonder
When we talk about those gorgeous, fragrant sweet peas (often called garden peas or Lathyrus odoratus), we’re usually talking about annuals. Technically, they are part of the vetch family, but most of us just know them as the stars of the cottage garden.
Since they are annuals, they have to grow from seed to a full 6-foot-tall climbing machine every single year. Even though you can’t really get them in the ground until late April, they manage to hit their max height in just a few weeks. This makes them the perfect “quick fix” if you need a lush, colorful privacy screen in a hurry. Plus, they do great in large containers on a sunny balcony!
Support is Key
Sweet peas produce long, delicate vines that are surprisingly thin. On their own, they aren’t sturdy enough to stand tall; they’ll just end up in a tangled heap on the ground. To get that vertical “wow” factor, you need to provide a trellis or support system almost immediately after sowing.
- Fences are perfect.
- Specialized trellises or bamboo poles work great too.
- Aim for a height of at least 5 feet.
- Keep the supports thin—if the wire or wood is too thick, those tiny tendrils won’t be able to grab hold.
The best part? You don’t really need to tie them up or worry about complicated pruning. Trimming is usually only necessary if a stray vine gets in the way or if the plant is getting a bit too tall for its britches.
Getting a Head Start
If you’re as impatient as I am, you can start your seeds indoors as early as February. This gives you much sturdier plants and an earlier blooming season. Just remember: don’t move them outside until the threat of frost has passed in mid-May, as they aren’t fans of the cold.
When planting them out, find a sunny spot and space them about 4 inches apart for a full, bushy look. Try to pick a spot that’s protected from high winds so those delicate vines don’t snap.
Keeping Your Sweet Peas Happy
These plants are thirsty! They evaporate water quickly, so you’ll need to water them regularly on warm days. To keep the flowers coming all summer long, give them a little fertilizer every now and then and be sure to “deadhead” (pinch off) any faded blooms. I also highly recommend a thick layer of mulch. It keeps the roots cool and moist while slowly feeding the soil as it breaks down.
Pro Tip:
Only let a few seed pods mature at the end of the season. If you let them all go to seed, they might pop up all over the place next year and start acting like a weed!
