Carol Koesel uses Genista lydia in her garden and provided our readers some great images and information about this little used shrub. For people with sandy soil, this could be a great choice for adding an interesting, colorful spring specimen. Here’s what Carol has to say:
I am not a big fan of “hot” colors in my yard. I lean toward the cool blues and purples, pale pinks and multiple shades of green, but in the spring and early summer I appreciate pops of yellow to light up darker corners.
I’m also a big fan of woody ornamentals, natives as well as the more unusual genuses.
I think I first encountered Genista in the “High Country Gardens” catalog, or maybe it was in Dirr’s illustrated Hardy Trees and Shrubs, but it was the perfect plant for the shrub border screen in the back yard. I did find it container grown locally, but have not seen it since. Perhaps it can be ordered.
Genista lydia is a low growing groundcover that matures to about 1 foot tall and up to 5 feet across, and can be easily shaped or pruned if necessary. Said to be hardy in zones 6-8 (9), it has done well in my yard for the past 8 years. It prefers dry, sandy soil and full sun; it detests wet feet. For two to three weeks in late May to early June it literally vibrates with chrome yellow color. Otherwise it is a prostrate, small-leaved, dark olive green.
It under plants a Blackhaw viburnum trained to a standard and a Cornelian Cherry dogwood in this border and is backed by ‘Emerald Green’ arborvitae, ‘Black Lace’ elderberry and ‘Tiger Eye’ sumac.
Monroe County Master Gardener Association 
Great photos! I love mine, too. Snow’s nursery sold it years ago and then there was a version called ‘Bangle’ among the Proven Winners Color Choice shrubs, so it appeared in garden centers like Lowe’s and Meijers for a year or two. I haven’t seen any recently, either.