When to Plant Brussels Sprouts in Vacaville, CA
Published: April 24, 2026
Brussels Sprout Planting Dates for Vacaville, CA
| Start seeds indoors | February 15–22 |
| Last frost (average) | March 22 |
| Transplant outdoors | June 14–24 |
| Minimum soil temperature | 45°F |
| Expect first harvest | September 2 – September 22 |
| Fall crop planting | August 11–21 |
| Fall crop harvest | October 30 |
| First fall frost (average) | November 10 |
⚠ Brussels sprouts are planted in midsummer for a fall harvest. Count back 90 days from your first fall frost to find the transplant date. Start seeds indoors 4–6 weeks before that date. Flavor improves after frost.
Best Brussels Sprout Varieties for Vacaville, CA
Consult a Vacaville-area nursery or your state extension office for brussels sprout varieties proven in Zone 6b.
Growing Brussels Sprouts in Vacaville
Vacaville sits in Zone 6b, with an average last frost of March 22 and first fall frost around November 10 — giving a 233-day frost-free growing season. Cool-season crops like brussels sprout benefit from Vacaville's cooler spring and fall windows, when temperatures stay in the 55–75°F sweet spot that produces the best flavor and least bolting.
Vacaville's moderate climate supports brussels sprout on the standard transplant calendar with minimal special accommodation. Succession planting — sowing fresh seeds or setting new transplants every 2–3 weeks through spring — stretches the harvest window and gives you a backup crop if pests hit the first planting.
Vacaville's mixed soil conditions vary block by block — get a soil test if you have not in three years. Generally, a base of quality compost (2 to 3 inches annually) and consistent watering at 1.5 inches per week serves brussels sprout well across most soil types found in Vacaville.
Brussels Sprout Calendar for Vacaville
| Month | Task |
|---|---|
| February | Start seeds indoors under grow lights |
| March | Last frost — harden off seedlings outdoors |
| June | Transplant outdoors into warm soil |
| September | Expect first harvest window to open |
| August | Start fall crop — transplants or direct sow |
| November | First fall frost — harvest remaining, end of outdoor season |
Brussels Sprout Tips for Vacaville Gardeners
- •Count back 90 days from first fall frost to find the transplant date — this is the most important Brussels sprout timing rule.
- •Pinch the top of each plant about a month before first frost — this channels energy into sprout formation.
- •Succession plant brussels sprout in Vacaville every 2–3 weeks through spring to extend the harvest window into summer.
Common Brussels Sprout Pests in Vacaville
- •Cabbage Worm — peaks July in Zone 6b (active May–September); green caterpillars on brassicas; apply Bt spray or use row covers.
- •Aphid — peaks July in Zone 6b (active May–September); monitor closely during peak season and treat early.
- •Cabbage Looper — peaks July in Zone 6b (active May–September); loop-walking green caterpillars; Bt spray works well.
Check plants every 2–3 days during peak season — early intervention prevents most infestations from becoming serious.
What to Plant with Brussels Sprouts in Vacaville
In Vacaville's moderate climate, Onion and Celery are the most beneficial plants to grow alongside brussels sprout. Onion deters carrot fly, aphids, and several root-zone pests through sulfur compounds. Keep brussels sprout away from Tomato — it competes for nutrients or shares pest pressure.
Frequently Asked Questions
When should I plant brussels sprout in Vacaville, CA?
In Vacaville (Zone 6b), start brussels sprout seeds indoors around February 15–22 and transplant outdoors around June 14–24. The city's average last frost of March 22 is the anchor date — count 5 weeks back for seed starting and 12 weeks forward for transplanting.
What zone is Vacaville, CA for brussels sprout growing?
Vacaville is USDA Zone 6b. For brussels sprout, this means a frost-free growing season of roughly 33 weeks running from March 22 to November 10. Cool-season crops like brussels sprout thrive in this zone with both spring and fall planting windows available.
When is brussels sprout harvest season in Vacaville?
Expect the first brussels sprout harvest in Vacaville around September 2, with harvest continuing through September 22. This is based on 80–100 days from transplant or direct sow. A fall crop planted August 11–21 adds a second harvest around October 30.
How long does it take to grow brussels sprout in Vacaville, CA?
From transplant or direct sow to first harvest, brussels sprout takes 80–100 days in Vacaville's climate. Based on a typical planting date of June 14–24, expect your first harvest around September 2. Vacaville's Zone 6b transition-zone climate produces maturity times right in the middle of the stated range.
What soil does brussels sprout need in Vacaville?
Vacaville's soil conditions vary block by block. Before planting brussels sprout, do a soil test (most state extension offices run them for $15–30). The test reveals pH, key nutrient levels, and organic matter content, so you can amend appropriately rather than guessing. Generally, 2–3 inches of compost annually improves most soils for vegetable production.