Cornflowers grow in shades of lavender-blue to purple. You'll find both annual and perennial varieties of the flower available for use in garden beds and borders. Starting purple cornflowers indoors allows you to control the planting time. Since cornflowers have a relatively short blooming period, start flowers throughout the spring and summer at different times and transplant them into the garden for a succession of blooms. Follow proper transplanting techniques to ensure that your plants stay healthy and able to bloom once you relocate them outdoors.
Prepare a well-drained garden bed in full sunlight as soon as the soil thaws enough to be worked in spring. Work a 2-inch layer of compost into the soil with a hoe to add nutrients and help water drainage from the bed.
Set the cornflower transplants outside one week before transplanting. Leave them outside in a covered area for two hours on the first day. Then gradually increase the time outside each day over the course of the week until they spend a full day outside. This prepares them for outdoor conditions and prevents transplant shock.
Dig each planting hole to the same depth as the nursery pot and twice as wide, using a spade. Space planting holes 12 inches apart.
Remove a transplant from the nursery pot. Grasp the seedling around the stem near the soil surface. Tap the container sides with the other hand to loosen it. Then pull the container off the soil and root ball.
Set the cornflower seedling in the planting hole so it's at the same depth as it was at in its nursery pot. Back-fill the soil into the hole and press it firmly around the plant with your hands.
Water the purple corn flowers immediately after transplanting. This collapses any air pockets in the soil around the roots so they can instantly begin taking in water and nutrients from the soil.