Gardening with Wildflowers - Phacelia

The vegetable gardens are still in the process of being changed over to raised beds, but our wildflowers are in full bloom. Pictured is Phacelia integrifolia, also commonly known as Scorpion Weed, Wild Heliotrope or Gypsum Phacelia. It is lovely used as an ornamental and is beginning to be widely used as a cover crop or "green manure".

There are about 200 species of the genus Phacelia. They grow wild, are cultivated as ornamental ground cover or in container gardens almost world wide.

When used as a cover crop, they are usually planted in late August in the temperate zones and winter over until late February or very early March. For full benefit as a green manure, they should be tilled or turned into the soil prior to the first blooms. This particular species does not fix nitrogen in the soil, but due to its vigorous growth, will prevent most weeds getting a foothold in fallow ground. The plants do not make a woody stem and break down quickly once tilled so they are a ready source of nutrients for the new spring crop. Their dense growth habits also help prevent erosion and topsoil loss due to winter storms.

They are exceptionally easy to grow in containers. This species is partial to gypsum and caleche or alkaline soil. Many others will do better in standard potting soils. Seed packets and nursery stock will have any special requirements noted in the instructions provided.

The photos are a bit misleading. Each flower is only about 1/4" across and the plant pictured here is less than 6" tall. This can vary a lot with the water and nutrients available, as well as the species. They come in different colors ranging from white to pale pink and pale blue to deep purple.

It is one of my favorites, but some caution is advised. A skin rash similar to poison oak or ivy rashes can occur in sensitive individuals. They can also be somewhat invasive to surrounding yard and field because they seed so readily.