Growing Radish

Raphanus sativas : Brassicaceae / the mustard or cabbage family

Jan F M A M J J A S O N Dec
P P P P P P P P P P P P

(Best months for growing Radish in Australia - sub-tropical regions)

  • P = Sow seed
  • Easy to grow. Sow in garden. Sow seed at a depth approximately three times the diameter of the seed. Best planted at soil temperatures between 8°C and 30°C. (Show °F/in)
  • Space plants: 3 - 5 cm apart
  • Harvest in 5-7 weeks.
  • Compatible with (can grow beside): Chervil, cress,lettuce, leeks, spinach, strawberries, tomatoes
  • Avoid growing close to: Hyssop, gherkins

Your comments and tips

02 Apr 15, Costa (USA - Zone 9b climate)
The greens of radishes are also edible. Eat raw when the leaves are small and tender. More mature greens before turning woody or the stem becoming hard and dark or before leaves start turning yellow can be steamed or boiled....A little lemon, salt, olive oil and you have some great tasting and healthy greens.Great over a bed of rice. Also good for juicing.
26 Mar 15, Lola Diver (Australia - cool/mountain climate)
What is the best type of fertilizer to use for my radishes?
29 Dec 17, Mike (Australia - temperate climate)
Radishes need good soil - not overly rich. If too rich the plant will produce a lot of leaves. Good free draining soil and water every day.
13 Mar 15, Kristin Litwiler (USA - Zone 5a climate)
What is the best region of the US to grow radishes? What region is Arkansas in? I haven't been able to find that on the Web nor a picture of the US divided into its' regions as I've seen on seeds pack backs.
30 Oct 22, Dan von Bose (USA - Zone 8a climate)
NW third of Arkansas is zone 7, rest is 8. Type "USDA zone map" into a search engine (I used Google).
10 Mar 15, Kay Green (Australia - temperate climate)
Recent radish purchases from a variety of shops have all been like rocks. Almost break my dentures. Is it the time of year or just a weather phenomenon?
29 Dec 17, Mike (Australia - temperate climate)
Radishes grown slow with irregular watering tend to be hard and bitter I think. Grow them quick with plenty of water.
19 Oct 14, Sheila Graham (Australia - temperate climate)
I have raddish from seed, lots of them. And I have some from seedling. I used Seasol two weekly. The seedlings are ready to eat. I will leave the seeds for another two weeks or so.
09 Oct 14, claire storey (Australia - temperate climate)
What type of fertilizer do you use for radishes. How do you get good root development
11 Sep 14, suzette (Australia - temperate climate)
How much fertiliser is needed for radishes? No root development and lots of leaves makes me think too much fertiliser.
Showing 81 - 90 of 144 comments

Your Black Spanish Radishes are a a winter variety - Germination (seed to seedling) happens at temps of 50f - 75f (10c - 24c) and will take 6 to 10 days. --they take anywhere from 30 to 70 days to mature (that is from sprouted seedling to harvest) - you can harvest them when they are about 3" to about 5". Plant anywhere from about two months before the first expected fall frost to 3 weeks before the first expected fall frost. Your best option is to figure out your first expected frost date - count back 8 weeks and call that your "expected planting date" - then check LAST years temperatures at or around your "expected planting date" -- if the temperatures sync up with the germination temperatures (10c - 24c) for Black Spanish Radishes, then it is a good time to plant, if not try and tweak your "expected planting date" so you will have the correct germination temperatures - and enough time for your radishes to grow. The reason your days to harvest has such a wide range is: you can harvest from 3" up to 5" -- additionally, when planting closer to fall/winter the number of hours of sunlight (and the intensity) varies a lot - for example: in my area on August 10th I get 14:36:05 hours of daylight .... and on September 30th I get 11:43:20 hours of daylight -- both are fairly good planting dates with August 10, 2022 having temps of (high/low) 20.4c/ 12.8c AND September 30th having temps highs of 20.4c and lows of 8.7c ==> but September has about 20% less daylight hours and the suns intensity is much weaker -- this means radishes planted in September will take longer to grow and mature than radishes planted in August.

- Celeste Archer

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This planting guide is a general reference intended for home gardeners. We recommend that you take into account your local conditions in making planting decisions. Gardenate is not a farming or commercial advisory service. For specific advice, please contact your local plant suppliers, gardening groups, or agricultural department. The information on this site is presented in good faith, but we take no responsibility as to the accuracy of the information provided.
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