Sowing and growing radishes in a pot
If one vegetable is made for beginners, it is the radish. Four weeks after sowing you pull the first roots, it needs almost no depth, and it keeps growing in partial shade. That is exactly why radishes appear in nearly every windowsill or balcony plan.
At a glance
- Light
- 4 hours of light is enough, partial shade is fine
- Pot depth
- Pot 15 cm deep
- Sowing
- March to September, resow every two weeks
- Harvest
- 4 to 6 weeks after sowing
- Water
- Evenly moist, never let it dry out
- Level
- Very easy
Sowing
Sow one centimetre deep, leaving three to five centimetres between seeds. That looks generous for such a small seed, but a radish needs the room to form a root — too close together and you harvest nothing but leaves.
Sow a new row every two weeks rather than everything at once. That gives you radishes from March to September instead of thirty roots ripening in the same week.
Care
Radishes ask for little beyond steady moisture. If the compost dries out in between, the root turns hard, woody and hot — and watering afterwards will not undo it.
In full summer sun radishes bolt quickly. In July and August, put the pot in partial shade rather than the hottest spot on the balcony.
Harvesting
Pull them as soon as they reach the width of a coin. Leaving them longer does not improve the flavour: they turn hollow, spongy and sharp.
The leaves are edible and taste peppery — use them in a salad or soup instead of binning them.
Common mistakes
Leaves but no root almost always means sown too densely, too little light, or too much nitrogen in the compost. Thin to five centimetres apart.
Split roots come from drought followed by a heavy watering. A little every day beats a lot once a week.
Frequently asked questions
Why do I get leaves but no radish?
Usually the plants sit too close together or get too little light. Thin to five centimetres apart and move the pot somewhere brighter. Very rich compost does the same thing: plenty of nitrogen pushes the plant into leaf rather than root.
Can radishes grow indoors on a windowsill?
Yes, as long as the pot is fifteen centimetres deep and gets at least four hours of light. A north-facing window is too dark; east or west works well.
How often can I resow?
Every two weeks from March to September. Do refresh the top layer of compost after a few harvests.
Updated on 2026-08-25
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