The primrose is an annual flower with pastel-colored blossoms that come in clusters on leafless stalks. Cultivars of the primrose have origins in both Europe and China. The primrose is popular with gardeners because it is easy to grow. With a few simple precautions it can be grown successfully in a greenhouse or indoors as a houseplant.
Selecting a Plant
If you buy a primrose from a garden center, it will likely be a hybrid. Just a few kinds of primrose can be grown successfully indoors, including the English primrose (Primula polyantha) and the Fairy primrose (Primula polyantha). Choose a plant with several tight buds and a few open flowers. A fully flowering plant is not as preferable.
If you start your primroses from seed, plant in a mixture of moist perlite and peat. To prevent moisture from escaping, cover with a plastic bag secured by a rubber band. Place under a fluorescent grow light.
Keep your primrose in an area that is well lit, but not excessively warm. A fluorescent grow light is good. You do not need to blast a primrose with an expensive metal halide or high pressure sodium growing lamp.
Your pot should have a hole in the bottom so that it can drain. Plant in a mixture of part perlite or coarse sand, one part humus or moist peat moss, and one part garden soil. If you buy a potting soil, it should be a good general-purpose mix that retains water yet still drains well. If it is not well aerated, add perlite, sand or peat moss.
Temperature, Humidity & Watering
Keep indoor primroses at normal indoor temperature. The amount of humidity is not critical.
Use warm water to keep the soil evenly moist.
To avoid stem rot, make sure that the crown (where the stem meets the roots) is above the soil.
Feed evenly every two weeks when it is growing and weekly when it is about to flower. Use 4-12-4 fertilizer, which encourages blossoming.