Growing Flower Sprouts: A Complete Profile
By Growing Home Greens Team · August 10, 2026
Flower Sprouts is a separately trademarked kale x Brussels sprouts cross from a different breeding line than Kalettes, though the two are similar in concept: small, ruffled, purple-and-green florets running up a tall stalk instead of the tight round sprouts of a standard Brussels plant.
Fertile soil, steady water
Best florets come from fertile soil with a pH between 6.5 and 7.5. Fertilize at roughly 75 percent the nitrogen rate used for Brussels sprouts, and irrigate through dry stretches to keep growth even; this crop has a heavier nitrogen appetite than most brassicas here.
Culture matches Brussels sprouts
Start seed indoors about 6 weeks before the last frost, sown a quarter to a half inch deep, then transplant out on the same schedule as Brussels sprouts. The overall plant size and timeline track closely with Brussels sprouts, with the payoff being a more colorful, ruffled harvest at the end.
Flower Sprouts has no well-established companion pairings, and nothing it needs to be kept away from. At 1 plant per square foot, it’s a colorful brassica option for the Garden Designer, alongside Kalettes or standard Brussels sprouts for comparison.
Source: Flower Sprouts: Key Growing Information, Johnny’s Selected Seeds.
Companion planting guide for Flower Sprouts · Find your planting dates
Typically viable in USDA zones 2-11. Not sure your zone? Look it up by ZIP code.
Mature height: 2-3 ft
Method: Start indoors: Start indoors from seed, then transplant outside. It needs a head start most zones can't give it by direct-sowing alone.
When to plant Flower Sprouts, by zone
Every zone Flower Sprouts grow 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 & 2b | Apr 8–Apr 15 | May 6–May 13 | Aug 14–Aug 21 |
| 3a & 3b | Apr 18–Apr 25 | May 16–May 23 | Aug 24–Aug 31 |
| 4a & 4b | Apr 3–Apr 10 | May 1–May 8 | Aug 9–Aug 16 |
| 5a & 5b | Mar 29–Apr 5 | Apr 26–May 3 | Aug 4–Aug 11 |
| 6a & 6b | Mar 14–Mar 21 | Apr 11–Apr 18 | Jul 20–Jul 27 |
| 7a & 7b | Feb 27–Mar 6 | Mar 27–Apr 3 | Jul 5–Jul 12 |
| 8a & 8b | Feb 11–Feb 18 | Mar 11–Mar 18 | Jun 19–Jun 26 |
| 9a & 9b | Jan 4–Jan 11 | Feb 1–Feb 8 | May 12–May 19 |
| 10a & 10b | Dec 19–Dec 26 | Jan 16–Jan 23 | Apr 26–May 3 |
| 11a & 11b | Nov 20–Nov 27 | Dec 18–Dec 25 | Mar 28–Apr 4 |
Harvest dates are about 100 days after the sow or plant-out date, not after starting seeds indoors.
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 Flower Sprouts plants fit per square foot?
Spacing: 1 per square foot (square-foot-gardening spacing). Mature height: 2-3 ft.
Good companions for Flower Sprouts
- Radish: Radish (including the daikon form) is a documented trap crop for flea beetles, which prefer its mustard oils over other brassicas and can be sacrificed or pulled once infested: the same research cited on the radish page.
Full companion guide, including what to keep away from Flower Sprouts →
Varieties worth considering
- Straight-species Flower Sprouts (Brassica oleracea): Johnny's Selected Seeds sells this as its own trademarked line, a separate breeding program from Kalettes though similar in concept; the culture and floret style are traits of the line itself. (source)
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 Flower sprout seeds
None of the seed suppliers we list carries Flower sprout seeds right now. A local garden center or a specialty seed house is the place to look.
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 Flower Sprouts" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)
Pin this for later
Growing Flower Sprouts: A separately trademarked kale x Brussels sprouts cross from a different breeding line than Kalettes, with small, ruffled, purple-and-green florets along a tall stalk.
Save to Pinterest