California flannelbush is a gorgeous yet tough evergreen shrub or small tree with large, stunning yellow flowers and fuzzy, lobed evergreen leaves. It occurs in California, central Arizona, and northern Baja California, Mexico. In the wild it is most often found on dry sites in mountainous areas with nutrient poor, rocky, or coarse soils, mainly in chaparral, grassland, oak woodland or pine forest habitats. It is a fire dependent and fire adapted species that germinates most often in the post-fire environment, and it can sprout back after being top-killed in wildfire.
California flannelbush flowers in late spring to early summer depending on elevation and can grow up to about 30 feet tall, but it is usually much shorter, typically growing 5-15′ tall. It is amenable to heavy pruning and can easily be kept at a shorter stature. California flannelbush prefers full sun and low to no summer irrigation. It is highly attractive to pollinators. We find that carpenter bees are one of its main pollinators in our neck of the woods.
*Caution: California flannelbush has small, irritating hairs on the leaves, stems and seed pods that can make you itchy with direct contact with skin. The hairs can cause a rash or allergic reaction. Avoid touching the plant with your gloves and then rubbing your eyes, as the tiny hairs can be an eye irritant as well. The “flannel” in flannelbush is more of an armor than a blanket. The irritating hairs help keep mammal browse down, but it is said that deer will still occasionally eat flannelbush, although in our experience, the deer leave it alone in our gardens and it appears to be deer resistant, but that may vary depending on location. As long as you are careful and wear gloves and long sleeves when you prune this plant, you should be fine working with this species. This is just a note of caution for your awareness.
California flannelbush (Fremontodendron californicum) seed packets contain approximately 45 seeds per packet.
Seed Germination Instructions
Flannelbush seeds benefit from scarification to help trigger springtime germination. Seeds may be scarified mechanically using sandpaper rubbed on the seed coat, or nicking with a small knife. Or they can be soaked in hot (not boiling!) water, and left to cool for several hours. After heat treatment or scarification, sow the seeds outside in fall to early winter. The seeds need approximately 90 days cold-moist stratification after heat treatment or scarification. In areas with cold enough winters this can be achieved outside in natural conditions, or in areas with mild winters, artificial methods can be used.