Yarrow Gilly Flower as the 49ers named this sweet little annual California wildflower. Frilly green foliage gives rise to 10″ stems supporting violet to sky blue flowers. Blooms May-July in our climate. Very easy to naturalize in open disturbed sites. A great reblooming pollinator wild flower. Makes sweet little bouquets as well. Full sun and lose un compacted soil- turn the soil to incorporate oxygen before planting. Light summer water keeps things going. Or it will finish with drought setting seed for the next years performance.