Digitalis grandiflora
CHRISTINA GEER Taxonomy
Kingdom: Plantae Subkingdom: Tracheobionta Superdivision: Spermatophyta Division: Magnoliophyta Class: Magnoliopsida Subclass: Asteridae Order: Scrophulariales Family: Schrophulariaceae Genus: Digitalis Species: Digitalis grandiflora Taxonomy
Previously known as Digitalis ambigua
Commonly known as Yellow Foxglove Geographic Distribution
native to the temperate parts of Europe and western Siberia
naturalized in the northeastern and north central parts of the United States, as well as parts of Ontario, Canada
found up to altitudes of 500m Geographic Distribution Native Habitat
commonly found: along stream banks in mixed and deciduous forests along forest edges Taxonomic Description
Biennial: First year as basal rosette of leaves, will bolt and flower in second year campanulate flowers are yellow, often with brown speckles hardy in zones 3-8 tolerant of shade and moisture May persist 5-8 years source of digitoxins Cultivars on the Market
There are many cultivars of Digitalis purpurea, including ‘Foxy’, which will bloom in one year. Ball seed sells Digitalis grandiflora as Digitalis ambigua, as well as a dwarf form, Dwarf Carillon Product Specifications
Long bloom time (at least 8 weeks/ year) Persists in landscape for many years A selection with lower toxin levels could be a big selling point Market Niche
Limitations: Toxicity, biennial Sales strategy: Robert Frost tie-in “quaint,” “cottage,” “old-fashioned,” and “picturesque” Use the common name, Foxglove, rather than the more medical-sounding Digitalis Pictures of planted cottage gardens Display with other classic cutting garden flowers Provide sample garden plans Cottage Gardens Production Schedule
Seed propagated, cold period required for bloom
Ball seed recommends sowing in either July, and overwintering at temps of 30-35F, or sowing in October, and overwintering at 35-40F before finishing at 60-65F.
The second option would compete for heated greenhouse space in the winter and early spring Experiments
Germination: 86% of 288 seeds germinating within 7 days, and 89% within 14 days
Pro-Gibb: A study on Digitalis purpurea ‘Foxy’ found that one application of Pro-Gibb at 10-50 ppm reduced time to bloom by about 30 days. Higher rates decreased quality.
I sprayed 9 of 18 plants with 50 ppm Pro-Gibb, leaving 9 as control. Works Cited
Anisko, Tomasz. When Perennials Bloom: an Almanac for Planning and Planting. Google Books. 3 March 2012. http://books.google.com/books?id=ODYpMZXFnSQC&pg=PA173&dq=digitalis +grandiflora&hl=en&sa=X&ei=4YQ0T6blJMnFsQKOxNSxAg&ved=0CE4Q6AEwAQ#v=onepage&q=digitalis %20grandiflora&f=false Armitage, Allan. Armitage’s garden Perennials. Google Books. 3 March 2012. http://books.google.com/books?id=3IqCm2rsuEEC&pg=PA108&dq=digitalis +grandiflora&hl=en&sa=X&ei=4YQ0T6blJMnFsQKOxNSxAg&ved=0CFoQ6AEwAw#v=onepage&q=digitalis %20grandiflora&f=false Ball Plant Information. 2012. Ball Horticultural Company. 20 March 2012. http://www.ballhort.com/growers/plant_info.aspx?phid=023100051000001&dispmode= Germplasm Resources Information Network [Online Database]. 2012. United States Department of Agriculture, National Genetic Resources Program. 3 March 2012. http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?102280 Keever, Gary. “Response of ‘Foxy’ Foxglove to GA3 and Cold Treatment.” Journal of Environmental Horticulture. 1998. Horticultural Research Institute. 3 March 2012. http://www.hriresearch.org/docs/publications/JEH/JEH_1999/JEH_1999_17_1/JEH%2017-1-35-38.pdf Kole, Chittaranjan. Wild Crop Relatives: Genomic and Breeding Resources. Google Books 3 March 2012. http://books.google.com/books?id=UdDMCfgr4dEC&pg=PA105&dq=digitalis +grandiflora&hl=en&sa=X&ei=p4o0T62qGfTLsQL9pvSsAg&ved=0CHsQ6AEwCTgK#v=onepage&q=digitalis %20grandiflora&f=false Natural Resources Conservation Service Plants Database. 2012. United States Department of Agriculture. 3 March 2012. http://plants.usda.gov/java/profile?symbol=DIGR4
Questions?