Propagation
Pansies grow from seeds, so can be planted directly in the ground. However, starting indoors 6 to 8 weeks before the last frost in your area will achieve the earliest blooms. Their tiny seeds germinate slowly, usually in 10 to 20 days, but boy, are they worth the wait! As biennials, they self-sow. A biennial is a plant that requires all or part of 2 years to complete its life cycle. Read more, here: Annual, Biennial, Perennial, what's the difference?
Pansies come in almost every color including velvety black and spectacular blues! They like full to partial sun, and cool to warm weather. They aren’t fussy, and tolerate lots of soils, but wherever you put them, the planting medium should be freshly loosened and contain some organic material.
Pansies are members of the Violaceae family but they have bigger flowers than Johnny Jump-Ups (Viola tricolor) and Viola.
Troubles
Slugs are Pansies' most common issue. Use insecticides or fungicides exactly according to directions, and only when you know for sure what’s bugging them. For more info on diseases and pests, click here.
Pansies need plenty of moisture and good drainage. When the weather gets hot, they often get leggy and benefit from deadheading. Trim spent blooms as often as you can because they will make more!
Size and Spacing
Pansies grow in a rounded shape, 4”’ to 8” tall and up to 12”wide. Typical spacing is 6” to 10”. They’re super friendly and don’t mind being close for a fuller look. Just keep your eye on them, since tighter planting can make them more susceptible to insects or disease. Check out more info from Iowa State University about sizes and types of pansies by clicking here.
Edible Flowers
If you're hungry, Pansies' lovely flowers and leaves are edible and can be used for decorating cakes, salads and other foods. They’re often used for making syrup and natural dyes. Check out this link for more information: A Consumer's Guide to Edible Flowers