Sweet peas are a delicate, climbing variety of flower. The fragrant blossoms come in various shade of pinks, whites, and violets and are relatively easy to grow. There are a number of tips you can use in order to get the most out of your sweet pea seeds, including when to plant, where to plant, and how to plant. You should also read the instructions on your seed packets as seeds may vary among brands.
Sweet pea seeds can be sown either directly in the soil outside or started indoors before being transplanted. In climates where the ground freezes during the winter, the seeds should be directly sown into the ground approximately six weeks before the first frost for the plants to bloom in spring. The plants can also be prestarted in pots or trays in the early spring. These should be kept outside in a protected area, however, so that the plants are tough enough to survive being transplanted.
If a protected area is not practical, the sweet pea seeds can be sown indoors in late winter to early spring and taken outside periodically to build up a tolerance. In warmer climates where the ground does not freeze, you can sow your sweet pea seeds directly into the ground until mid-autumn for the flowers to bloom in the spring. If you are unable to plant your seeds in the fall, they can be planted in mid-spring all the way to June; however, this may result in later flowers with a much shorter period of blooming.
You should plant your sweet pea seeds in an area that will receive partial to full sunlight. The soil should drain well and be loamy and moist. Plant your seeds somewhere that you will be able to erect a fence or lattice as they will need a structure to climb. It is best to make sure that this is not too close to a wall in order to ensure the proper circulation of air and to make the flowers easier to pick.
Make sure you use fresh, undamaged seeds. It is helpful to soak sweet pea seeds overnight in water to loosen the skins and allow the seeds to absorb water. This helps improve germination rates and time. If some of the seeds fail to absorb water, you can gently nick the skin with a razor blade, fingernail, or sandpaper. Be careful not to cut into the seed itself.
Before you plant the seeds, fertilize the soil, and turn it over both to help it oxygenate and to distribute the nutrients more evenly. Plant the seeds in a furrow that is approximately 1 inch (2.5 centimeters) deep and spaced 2 to 3 inches (6 to 7 centimeters) apart so that they have ample room to grow. You can thin the plants out later, and this way, you will avoid having any bare patches if the seeds fail to germinate.
Fill the furrow with dirt, but be careful not to pile it into a mound over the seeds because this can make it more difficult for the seeds to grow. Place a hooped netting over the seeds to prevent birds from digging them up and eating them. Make sure that you remove the netting once the plants get tall enough to reach it; otherwise, they will cling to it. Finally, water the seeds. Do this using a watering can or similar attachment to provide a light sprinkle that will not erode the soil and expose the seeds.