How to grow rapini (broccoli raab)
Brassica rapa subsp. rapa · Brassicaceae · Vegetable
When to plant rapini (broccoli raab): the short answer
Sow outdoors about 3 weeks before the last frost; for a fall crop, sow about 8 weeks before your first fall frost. Seeds germinate in soil from 45 to 85°F, fastest near 70°F.
Cold winters (zone 5): sow Apr 4 – Apr 23, or sow Jul 31 – Aug 17 for a fall crop. Mild winters (zone 9): sow Sep 25 – Oct 12 for fall and winter harvests; the spring window (Jan 25 – Feb 13) closes before the summer heat. Skip the hottest months for rapini (broccoli raab). See every zone.
Rapini (Broccoli Raab) is a cool-season vegetable in the Brassicaceae family, almost always sown straight into the ground where it will grow. It wants full sun, though it tolerates a little afternoon shade in hot regions and steady, even moisture. From sowing to first pick is about 40–60 days. It handles frost well and a light freeze often improves the flavour.
Grower’s note: Not true broccoli - a fast turnip relative grown for its pungent leafy shoots and small buds, cut all at once just before the flowers open. A spring and fall crop; summer heat makes it bolt and turn harshly bitter.
Sowing
Sow about 0.5″ deep, into soil between 45–85°F — germination is quickest near 70°F. It comes up fast (5–10 days). It does not transplant well, so sow it in its final position rather than starting it in pots.
Spacing & layout
Give each plant about 5″ along the row with roughly 12″ between rows. On a square-foot grid that is 9 per square foot. Allow at least 12″ of loose, workable soil for the roots. It grows well in containers at least 8″ deep.
Fitting it to your season
As a cool-season crop, rapini (broccoli raab) does its best growing in the mild weather of spring and fall and tends to bolt or turn bitter in summer heat. A second sowing in late summer, timed to mature as the weather cools, is usually the better crop of the year — and light frost only sweetens it.
Quick facts
Growth stages: how long rapini (broccoli raab) takes to grow
From sowing to first harvest takes roughly 40-60 days (6-9 weeks), with seedlings appearing after 5-10 days in soil around 70°F.
When to plant rapini (broccoli raab)
When to plant rapini (broccoli raab) by USDA zone
Dates worked out from each zone’s typical frost dates for 2026. Find your zone on the zone map, or pick your state below for dates from its own frost dates. Zones 11 and above are frost-free, so timing there depends on heat and rain instead.
| Zone | Last / first frost | Start indoors | Sow or plant out | Fall or second sowing |
|---|---|---|---|---|
| Zone 3 | May 15 / Sep 15 | - | Apr 19 – May 8 | Jul 11 – Jul 28 |
| Zone 4 | May 10 / Sep 25 | - | Apr 14 – May 3 | Jul 21 – Aug 7 |
| Zone 5 | Apr 30 / Oct 5 | - | Apr 4 – Apr 23 | Jul 31 – Aug 17 |
| Zone 6 | Apr 15 / Oct 15 | - | Mar 20 – Apr 8 | Aug 10 – Aug 27 |
| Zone 7 | Apr 5 / Oct 25 | - | Mar 10 – Mar 29 | Aug 20 – Sep 6 |
| Zone 8 | Mar 20 / Nov 5 | - | Feb 22 – Mar 13 | Aug 31 – Sep 17 |
| Zone 9 | Feb 20 / Nov 30 | - | Jan 25 – Feb 13 | Sep 25 – Oct 12 |
| Zone 10 | Jan 30 / Dec 15 | - | Jan 4 – Jan 23 | Oct 10 – Oct 27 |
Companions
Onion, Beet
Tomato, Pole Bean, strawberry
Common problems
Pests: flea beetle, cabbage worm, aphids.
Diseases & disorders: clubroot, downy mildew.
Same family (Brassicaceae)
Rotate these so they don’t follow each other in the same bed year to year.
Questions gardeners ask
When should I plant rapini (broccoli raab)?
Sow outdoors about 3 weeks before the last frost; for a fall crop, sow about 8 weeks before your first fall frost. Seeds germinate in soil from 45 to 85°F. The table on this page gives dates for each USDA zone, and the planting calendar gives dates for your own state or ZIP code.
How long does rapini (broccoli raab) take to grow?
About 40-60 days from sowing to the first harvest. Seeds germinate in 5-10 days, fastest in soil around 70°F.
How much sun does rapini (broccoli raab) need?
It needs six or more hours of sun for the best growth, though four to six hours in partial shade is enough.
What soil pH does rapini (broccoli raab) need?
A soil pH between 6.0 and 7.5. Test before adding lime or sulfur - see the soil pH and testing guide.
How far apart should I plant rapini (broccoli raab)?
Space plants about 5 inches apart in rows 12 inches apart, or 9 per square foot in a square-foot bed. Sow seeds about ½ inch deep.
Can I grow rapini (broccoli raab) in a container?
Yes. Use a container at least 8 inches deep with drainage holes and a good potting mix, and water more often than you would in the ground.
Figures are typical home-garden ranges from Cooperative Extension planting guides, cross-checked against multiple state sources. Your variety and conditions will vary.