Editing Radish (section)

== Cultivation ==
[[File:Germinating radish.jpg|thumb|left|Newly germinated radishes at 10 days old]]
Radishes are a fast-growing, annual, cool-season crop. The seed [[Germination|germinates]] in three to four days in moist conditions with soil temperatures between {{convert|65|and|85|F|C|order=flip}}. Best quality roots are obtained under moderate day lengths with air temperatures in the range {{convert|50|to|65|F|C|order=flip}}. Under average conditions, the crop matures in 3–4 weeks, but in colder weather, 6–7 weeks may be required.<ref name=Seaman>{{cite web|url=http://veg-guidelines.cce.cornell.edu/28frameset.html |title=Turnips and Radishes |last1=Seaman |first1=Abby |date=2013-11-13 |work=Integrated crop and pest management guidelines for commercial vegetable production |publisher=[[Cornell University|Cornell Cooperative Extension]] |access-date=2014-07-29 |url-status=dead |archive-url=https://web.archive.org/web/20140723053939/http://veg-guidelines.cce.cornell.edu/28frameset.html |archive-date=July 23, 2014 }}</ref> Homegrown varieties can be significantly sharper. 

Radishes grow best in full sun in light, sandy [[loam]]s, with a [[soil pH]] 6.5 to 7.0, but for late-season crops, a clayey-loam is ideal. Soils that bake dry and form a crust in dry weather are unsuitable and can impair germination.<ref name="beattie1938">{{cite book |last1=Beattie |first1=James H. (James Herbert), b. 1882 |last2=Beattie |first2=W. R. (William Renwick), b. 1870 |author3=United States Department of Agriculture |title=Production of radishes |date=March 1938 |location=Washington, D.C. |publisher=United States Department of Agriculture; UNT Digital Library |type=Leaflet |number=57 |url=https://digital.library.unt.edu/ark:/67531/metadc1562/ |access-date=October 2, 2014 |author3-link=United States Department of Agriculture |archive-url=https://web.archive.org/web/20141006114841/http://digital.library.unt.edu/ark:/67531/metadc1562/ |archive-date=October 6, 2014 |url-status=live }} hosted by the [https://digital.library.unt.edu/browse/department/govdocs/ University of North Texas Government Documents Department] {{Webarchive|url=https://web.archive.org/web/20091203021903/http://digital.library.unt.edu/browse/department/govdocs/ |date=2009-12-03 }} Documents A to Z Digitization Project website. Retrieved on 2014-07-29.</ref><ref name="faust1996">{{cite news |last1=Faust |first1=Joan Lee |date=March 3, 1996 |url=https://www.nytimes.com/1996/03/03/nyregion/gardening-hail-the-speedy-radish-in-all-its-forms.html |title=Hail the Speedy Radish, in All Its Forms |newspaper=[[The New York Times]] |access-date=February 5, 2018 |archive-url=https://web.archive.org/web/20180205130201/http://www.nytimes.com/1996/03/03/nyregion/gardening-hail-the-speedy-radish-in-all-its-forms.html |archive-date=February 5, 2018 |url-status=live }}</ref><ref name="peterson1999">Peterson, Cass. [https://www.nytimes.com/1999/05/02/style/cuttings-radishes-easy-to-sprout-hard-to-grow-right.html "Radishes: Easy to Sprout, Hard to Grow Right"] {{Webarchive|url=https://web.archive.org/web/20180205184549/http://www.nytimes.com/1999/05/02/style/cuttings-radishes-easy-to-sprout-hard-to-grow-right.html |date=2018-02-05 }}. ''The New York Times'', May 2, 1999. Retrieved February 5, 2018.</ref>  Harvesting periods can be extended by making repeat plantings, spaced a week or two apart. In warmer climates, radishes are normally planted in the autumn.<ref name="beattie1938" /> The depth at which seeds are planted affects the size of the root, from {{convert|1|cm|in|frac=4|abbr=on}} deep recommended for small radishes to {{convert|4|cm|in|frac=2|abbr=on}} for large radishes.<ref name="peterson1999" /> During the growing period, the crop needs to be thinned and weeds controlled, and irrigation may be required.<ref name="beattie1938" />

[[File:Radijs planten (Raphanus sativus subsp. sativus).jpg|thumb|Growing radish plants]]
Radishes are a common garden crop in many parts of the world, and the fast harvest cycle makes them particularly suitable for children's gardens.<ref name="faust1996" /> After harvesting, radishes can be stored without loss of quality for two or three days at room temperature, and about two months at {{convert|0|C|F}} with a [[relative humidity]] of 90–95%.<ref name="Gopalakrishnan 2007" />

=== Companion plant ===
Radishes can be useful as [[companion plant]]s for many other crops, probably because their pungent odour deters such insect pests as [[aphid]]s, [[cucumber beetle]]s, [[Manduca quinquemaculata|tomato hornworms]], [[Coreidae|squash bugs]], and [[ant]]s.<ref name=EarthWood /> They can also function as a [[trap crop]], luring insect pests away from the main crop.<ref>{{cite web|url=http://www.knowledgebank.irri.org/IPM/cultCtrl/Trap_Crop.htm|title=Trap Crop|access-date=24 May 2011|archive-url=https://web.archive.org/web/20070322215153/http://www.knowledgebank.irri.org/IPM/cultCtrl/Trap_Crop.htm|archive-date=March 22, 2007}}</ref> Cucumbers and radishes seem to thrive when grown in close association with each other, and radishes also grow well with [[chervil]], [[lettuce]], [[pea]]s, and [[Tropaeolum|nasturtiums]]. However, they react adversely to growing in close association with [[hyssop]].<ref name=EarthWood>{{cite web |url=http://users.netconnect.com.au/~ewood/companion_planting.html |title=Garden Companions and Enemies |author=Ready, Barbara |date=1982-02-01 |work=EarthWood |access-date=2014-07-30 |archive-url=https://web.archive.org/web/20140701075634/http://users.netconnect.com.au/~ewood/companion_planting.html |archive-date=2014-07-01 |url-status=dead }}</ref>

=== Pests ===
As a fast-growing plant, diseases are not generally a problem with radishes, but some insect pests can be a nuisance. The larvae of [[flea beetle]]s live in the soil, but the adult beetles cause damage to the crop, biting small "shot holes" in the leaves, especially of seedlings. The [[Contarinia nasturtii|swede midge]] (''Contarinia nasturtii'') attacks the foliage and growing tip of the plant and causes distortion, multiple (or no) growing tips, and swollen or crinkled leaves and stems. The larvae of the [[Delia radicum|cabbage root fly]] sometimes attack the roots. The foliage droops and becomes discoloured, and small, white maggots tunnel through the root, making it unattractive or inedible.<ref name=Seaman />