Growing Radishes: A Complete Profile
By Growing Home Greens Team · July 18, 2026
Radishes are the fastest crop you can grow in a home garden, 25 days from seed to harvest, direct-sown as early as four weeks before your last frost. They’re also useful beyond the kitchen: radish is a documented trap crop that draws cucumber beetles away from more valuable plants.
Direct-seeding straight into the bed
Direct-seed straight into the bed; radishes don’t transplant well and don’t need to, given how fast they mature. At 16 plants per square foot, they’re one of the densest crops available, which makes them a natural filler in gaps between slower-growing neighbors. Check roots starting around three weeks in. Radishes left in the ground too long past maturity turn pithy and hot rather than crisp.
Small roots and cracked skins
Roots that stay small and never bulb up are usually a spacing or soil problem. Radishes crowded too tightly compete with each other for room. Cracked or split roots are typically from inconsistent watering; a dry stretch followed by a heavy soak causes the root to swell too fast for its skin.
A decoy for cucumber beetles
Radish is a documented trap crop for cucumber beetles, making it a useful companion near cucumbers. See the full companion guide for radish. Its speed and density make it a good gap-filler in the Garden Designer: sow it in a spot that will open up before a slower crop needs the space.
Companion planting guide for Radish · Find your planting dates
Typically viable in USDA zones 2-10. Not sure your zone? Look it up by ZIP code.
Mature height: 0.5-1 ft
Method: Direct sow: Direct-sow outside. It doesn't transplant well, or doesn't need the extra time indoors.
When to plant radish, by zone
Every zone radish grows in. Pick your zone in the header and it will be highlighted here. Each zone links to its full page.
| Zone | Start indoors | Sow or plant out | Harvest |
|---|---|---|---|
| 2a & 2bSpring window | Not usually | Apr 22–Apr 29 | May 17–May 24 |
| Fall window | Not usually | Jul 24–Aug 7 | Aug 18–Sep 1 |
| 3a & 3bSpring window | Not usually | May 2–May 9 | May 27–Jun 3 |
| Fall window | Not usually | Jul 28–Aug 11 | Aug 22–Sep 5 |
| 4a & 4bSpring window | Not usually | Apr 17–Apr 24 | May 12–May 19 |
| Fall window | Not usually | Aug 12–Aug 26 | Sep 6–Sep 20 |
| 5a & 5bSpring window | Not usually | Apr 12–Apr 19 | May 7–May 14 |
| Fall window | Not usually | Aug 27–Sep 10 | Sep 21–Oct 5 |
| 6a & 6bSpring window | Not usually | Mar 28–Apr 4 | Apr 22–Apr 29 |
| Fall window | Not usually | Sep 6–Sep 20 | Oct 1–Oct 15 |
| 7a & 7bSpring window | Not usually | Mar 13–Mar 20 | Apr 7–Apr 14 |
| Fall window | Not usually | Sep 16–Sep 30 | Oct 11–Oct 25 |
| 8a & 8bSpring window | Not usually | Feb 25–Mar 4 | Mar 22–Mar 29 |
| Fall window | Not usually | Oct 2–Oct 16 | Oct 27–Nov 10 |
| 9a & 9bSpring window | Not usually | Jan 18–Jan 25 | Feb 12–Feb 19 |
| Fall window | Not usually | Oct 27–Nov 10 | Nov 21–Dec 5 |
| 10a & 10bFall window | Not usually | Sep–Mar | ~25 days after direct-sowing |
Harvest dates are about 25 days after the sow or plant-out date.
Zone 2 sows before zone 3 here, which looks wrong and is not. USDA zones rank winter cold, not season length, and zone 2 is mostly interior Alaska, where hard winters come with warm summers. More on what a zone measures.
See exact start-indoors, direct-sow, and harvest dates for your zone →
How many Radish plants fit per square foot?
Spacing: 16 per square foot (square-foot-gardening spacing). Mature height: 0.5-1 ft.
Soil & water: pH 6.2-6.5. Needs well-drained soil. Amend with lime if soil pH falls below 6.2.
Good companions for radish
- Cucumber: Reputed as a trap crop that draws cucumber beetles away, but the documented trap-crop research for cucumber beetles points to Blue Hubbard squash specifically, not radish. Radish IS a real, documented trap crop, but for flea beetles on brassica crops: a different pest and crop pairing than this one. Treat this specific pairing as garden tradition, not measured evidence.
Full companion guide, including what to keep away from radish →
Varieties worth considering
- Rover (F1): Listed by the seed company at 21 days to maturity with a 'performs well under heat stress' rating, an early option if you want the fastest possible turnaround. (source)
- Cherry Belle: The most-reviewed radish in Cornell's variety database at 26 reviews and 4.3 stars, an All-America Selections winner with the round, red, classic look most people picture. The default choice if you just want a reliable radish and aren't optimizing for anything specific. (source) Buy seeds: Botanical Interests · True Leaf Market · Burpee · High Mowing Organic Seeds
- French Breakfast: Cornell rates it 4.8 stars, an oblong, bicolor (scarlet-to-white) type that the database notes adapts well to hot, dry conditions, useful for a summer sowing where round types like Cherry Belle tend to go pithy fastest. (source) Buy seeds: Botanical Interests · True Leaf Market · Burpee · High Mowing Organic Seeds
Why each variety is listed comes from the source shown next to it. We haven't grown these ourselves yet, so treat this as a research-backed starting point, not a personal endorsement. The buy links are separate from those sources: they go to seed suppliers that sell that exact variety, and we may earn a commission on some of them.
Where to buy radish seeds
Botanical Interests · True Leaf Market · Burpee · High Mowing Organic Seeds (each supplier's radish seeds)
The varieties we recommend above each have their own buy links, for the suppliers that sell that exact variety.
As an Amazon Associate we earn from qualifying purchases. Some links on this page also go to other retailers we may earn a commission from as an affiliate, at no extra cost to you. We only recommend products with a clear consensus of positive, independent reviews, or ones we bought and use ourselves. Each item on our gear page says which.
See it growing
Search YouTube for "growing radish" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)
Pin this for later
Growing Radish: The fastest crop in the garden: ready in under a month, and a genuine decoy for cucumber beetles.
Save to Pinterest