PlantFiles: Sweet Pea (Lathyrus odoratus)
- Lists basic habit and culture statistics, several flower photos, and observations and opinions of various gardeners.
- http://davesgarden.com/guides/pf/go/227/

Lathyrus - Cousins of the Sweet Pea
- Descriptions and photographs of a range of Lathyrus species, with cultivation notes from the holder of the National Plant Collection of Lathyrus.
- http://nccpg.com/lathyrus/

Lathyrus | Botany.com
- A description of the genus with notes on cultivation and propagation.
- http://www.botany.com/lathyrus.html

National Garden Bureau : Sweet Pea
- A fact sheet covering the history and types of sweet pea with advice on cultivation in different parts of the United States. Also mentions several other Lathyrus species.
- http://www.ngb.org/gardening/fact_sheets/fact_details.cfm?factID=17

RHS Sweet Pea Trial 2006
- The report on the Royal Horticultural Society 2006 assessment of new Sweet Pea cultivars suitable for garden and exhibition use.
- http://www.rhs.org.uk/plants/documents/SweetPea2006.pdf

Lathyrus.info
- Articles about sweet peas and other Lathyrus species.
- http://www.lathyrus.info

National Sweet Pea Society
- UK society aiming to disseminate knowledge of sweet peas and other Lathyrus species and to encourage and improve their cultivation. Includes information about the plants, shows and events, trials, and membership, and a photo gallery.
- http://www.sweetpeas.org.uk/

The Eckford Sweet Pea Society of Wem, Shropshire
- UK society provides information about the annual sweet pea show.
- http://www.virtual-shropshire.co.uk/attractions/972899604.html

BBC Gardening: Lathyrus odoratus, Sweet Pea
- Article providing brief history, recommended varieties, growing guide, and propagation tips.
- http://www.bbc.co.uk/gardening/plants/plantprofile_sweetpea.shtml