From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Hybrid parentagePoncirus trifoliata (Japanese bitter orange) x Citrus × paradisi (grapefruit)

Citrumelo or Citromelo (X Citroncirus spp.) is also called Swingle citrumelo trifoliate hybrid, because it is a cold hardy citrus hybrid between a 'Duncan' grapefruit and a trifoliate orange (Poncirus trifoliata (L.) Raf.), developed by Walter Tennyson Swingle.

Citrumelo is widely employed as a citrus rootstock,[1] being resistant to the severe citrus tristeza virus and to the Phytophthora foot rot as well as to blight, cold, and citrus nematode.[2] It produces yellow fruit which taste (if added sugar) and smell like an ordinary grapefruit.[3] The trees are very hardy and can survive temperatures as low as 30s (Fahrenheit).[4]


Trifoliate orange, according to Swingle, belongs to a citrus related genera, called Poncirus, while grapefruit equivocally belongs to the genus citrus, hence the botanical name X citroncirus is a hybrid genus, derived from citrus and poncirus.


  1. ^ ‘Swingle’ citrumelo propagation by cuttings for citrus nursery tree production or inarching. Scientia Horticulturae. April 2009;120(2):207–212. doi:10.1016/j.scienta.2008.11.001.
  2. ^ Citrumelo by Citrus Variety Collection
  3. ^ "Citrumelo of Nottingham". Retrieved 17 January 2017.
  4. ^ "Citrumelo Hardy Grapefruit". Retrieved 17 January 2017.

External links[edit]