Germinating Centranthus Ruber

Red valerian and keys of heaven both are common names for a plant botanically known as Centranthus ruber. It grows to a height of 18 to 24 inches, with a spread of 12 to 18 inches, and it produces deep red flower clusters in summer. An easy plant to grow, C. ruber does best within zones 5 through 9 on the U.S. Department of Agriculture Plant Hardiness Zone Map. Grow C. ruber in full sun, and deadhead frequently throughout the summer to prolong the blooming period. Start C. ruber seeds indoors, four to six week before the last frost.

Things You'll Need

• Container
• Seed starting mix
• Heat mat, optional

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Instructions

1. • 1

     Fill a container with seed starting mix. Any container will suffice, as long as it has holes in the bottom for drainage. Moisten the mix thoroughly.

   • 2

     Set the C. ruber seeds on the surface of the seed starting mix, and cover them with a 1/8-inch layer of the mix.

   • 3

     Leave the germination container in an area that remains 70 degrees Fahrenheit, or place the container on a heat mat set to 68 degrees.

   • 4

     Check the seed starting mix frequently for signs of drying. Keep it moist at all times during germination.