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 New Zealand - cool/mountain 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 46°F and 86°F. (Show °C/cm)
  • Space plants: 1 - 2 inches 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

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28 Oct 18, Mike (Australia - sub-tropical climate)
A bit of a contradiction - splitting maybe too wet and tough could be too dry. I find I grow the best radishes in the winter - a light watering each day.
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02 Nov 18, Mike (Australia - sub-tropical climate)
I picked some today - rough looking, probably a bit tough. They are longer than the winter ones - the root seems to be growing longer in search of water even though I water them every day or two. The winter ones are a lot better looking.
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22 Oct 18, Jean (Australia - sub-tropical climate)
I grow radishes a few years ago and they were so hot and spicy and I wanted to have another go, but when I went to the shop they had three or four different type. I just want to know which ones are mild and I can grow here in Brisbane.
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06 Sep 19, Terry (Australia - temperate climate)
Most of the heat is in the outer - red - skin. As a small child I'd peel that away (thumbnail worked well) and eat the white flesh inside, which is much milder. The leftover skin can be used in cooking, where they lose the peppery taste. Another way to use overly hot radishes is therefore to cut them into halves or quarters, coat in oil, and roast them in a hot oven (say 220C) until coloured and not too watery inside (30 mins or more).
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23 Oct 18, Mike (Australia - temperate climate)
I have grown them for 40+ years and I think it has to do with watering and weather. Better grown into/in the winter - a more even growing conditions - smaller variation of temp and water in the soil. If grown in the hotter weather they can dry out a bit and I think this makes them hotter. Try and grow quickly. Pick as soon as they reach the required size. They will keep in the fridge for weeks.
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28 Jan 18, Alice (Australia - temperate climate)
You mentioned that Radishes are best planted at three times the seed's diameter. Could you suggest a specific depth for a variety such as a Cherry Radish?
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02 Feb 18, Mike (Australia - sub-tropical climate)
I received some cherry radish in the mail yesterday and it says 10mm deep.
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30 Jan 18, Mike (Australia - cool/mountain climate)
Just run the rake handle in the soil to make a small furrow 4-6mm deep. Shake a few seeds into one hand and then pick up a few with the other hand and drop along the furrow. When finished cover the seeds with 4-6mm of soil. Water them morning and night. You could put a piece of shade cloth over the top of them until they germinate.
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01 Aug 17, Corinne Young (Australia - temperate climate)
Can I grow Radishes in pots . Deep pots. I live in Capel , Western Australia.
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03 Aug 17, Bev (Australia - cool/mountain climate)
Your pot size must be relative to the size of the radish. Radishes come in sizes ranging from 2cm to 30cm & larger !
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Showing 51 - 60 of 145 comments
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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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