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How to Start Sweet Pea Seeds

By Bridget Kelly ; Updated September 21, 2017

The sweet pea is a vining annual plant that produces sweetly scented flowers. According to the National Gardening Bureau, the intensity of the scent of the sweet pea blossom can vary according to variety. In warmer areas with mild winters, sweet pea seeds can be sown directly into the garden from August to November. In colder climes, you can either plant your seeds in the garden a few weeks before the last frost, or you can start your seeds indoors.

Starting Sweet Peas Outdoors

Choose a spot in your garden that will get afternoon shade.

Pour a 2 inch layer of compost over the top of the soil and mix in well. Water the planting area thoroughly, and allow the soil to drain.

Dig a furrow, 1 inch deep, the length of the planting area.

Nick the surface of each seed lightly with nail clippers or a small knife, just enough to create a tiny break in the outer skin.Sow the seeds, 5 inches apart, in the furrow and cover lightly with soil.

When the seedlings have three sets of leaves, pinch the top set off, leaving two. This will encourage the plant to grow bushier.

Starting Sweet Peas Indoors

Nick the surface of the seed lightly with nail clippers or a small knife, just enough to create a tiny break in the outer skin.

Place the peat pots in a pan or tray and fill them with potting soil. Water the pots well and allow them to drain. Pour off the excess water in the pan.

Push the seeds, three to a pot, 1 inch into the soil and cover them lightly with soil. Place the entire pan into the plastic bag and secure the top. Place the bagged pan in a dark area to germinate. This should take about 10 days.

Remove the bag when the seedlings break the surface of the soil. Place the pan in a sunny, cool location. Thin out the weakest plants when they have two or three sets of leaves, leaving one plant per pot.

Plant the peat pots, 2 inches deep, and 6 inches apart, in the garden about a month before the last frost.


Things You Will Need

  • To start seeds outdoors:
  • Compost
  • Nail clippers or a small knife
  • To start seeds indoors:
  • Nail clippers or small knife
  • Peat pots
  • Tray or pan
  • Potting soil
  • Plastic bag with a re-sealable top, large enough to hold the pan or tray

About the Author


Based in the American Southwest, Bridget Kelly has been writing about gardening and real estate since 2005. Her articles have appeared at Trulia.com, SFGate.com, GardenGuides.com, RE/MAX.com, MarketLeader.com, RealEstate.com, USAToday.com and in "Chicago Agent" magazine, to name a few. She holds a Bachelor of Arts in English with a concentration in creative writing.