Sow Indoors or Outdoors: Early Sunrise coreopsis seeds have a weedy/wildflower hardiness to them and are most popularly sown outdoors directly after the frost. For earliest spring blooms, begin seeds indoors 6 – 8 weeks prior and harden off to a sunny place in the garden. Early Sunrise coreopsis can be kept indoors with plenty of sunlight. Germination will take 14 – 28 days in full lighting.