When to Plant Cabbage in Arvada, CO
Published: April 24, 2026
Cabbage Planting Dates for Arvada, CO
| Start seeds indoors | February 9–16 |
| Last frost (average) | March 30 |
| Transplant outdoors | March 9–19 |
| Minimum soil temperature | 45°F |
| Expect first harvest | May 8 – June 17 |
| Fall crop planting | August 9–19 |
| Fall crop harvest | October 8 |
| First fall frost (average) | November 1 |
⚠ Start cabbage indoors 6–8 weeks before last frost. Transplant 2–4 weeks before last frost. Very frost tolerant — withstands temperatures as low as 20°F. Also plant in late summer for fall harvest.
Best Cabbage Varieties for Arvada, CO
Consult a Arvada-area nursery or your state extension office for cabbage varieties proven in Zone 6a.
Growing Cabbage in Arvada
Arvada sits in Zone 6a, with an average last frost of March 30 and first fall frost around November 1 — giving a 216-day frost-free growing season. Cool-season crops like cabbage benefit from Arvada's cooler spring and fall windows, when temperatures stay in the 55–75°F sweet spot that produces the best flavor and least bolting.
Arvada's moderate climate supports cabbage 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.
Arvada's well-draining loam soils are among the best for cabbage growing — focus on annual organic matter additions (2 to 3 inches of compost) and consistent moisture during drier months. Water cabbage at 1.5 inches per week; loam holds moisture evenly without the drought-crack cycle of heavy clay or the rapid-drain losses of pure sand.
Cabbage Calendar for Arvada
| Month | Task |
|---|---|
| February | Start seeds indoors under grow lights |
| March | Transplant outdoors into warm soil |
| May | Expect first harvest window to open |
| August | Start fall crop — transplants or direct sow |
| November | First fall frost — harvest remaining, end of outdoor season |
Cabbage Tips for Arvada Gardeners
- •Space plants 18 inches apart — crowding reduces head size and promotes fungal disease.
- •Side-dress with nitrogen 3–4 weeks after transplanting to support rapid leaf formation.
- •Succession plant cabbage in Arvada every 2–3 weeks through spring to extend the harvest window into summer.
Common Cabbage Pests in Arvada
- •Cabbage Worm — peaks July in Zone 6a (active May–September); green caterpillars on brassicas; apply Bt spray or use row covers.
- •Cabbage Looper — peaks July in Zone 6a (active May–September); loop-walking green caterpillars; Bt spray works well.
- •Aphid — peaks July in Zone 6a (active May–September); monitor closely during peak season and treat early.
Check plants every 2–3 days during peak season — early intervention prevents most infestations from becoming serious.
What to Plant with Cabbage in Arvada
In Arvada's moderate climate, Onion and Dill are the most beneficial plants to grow alongside cabbage. Onion deters carrot fly, aphids, and several root-zone pests through sulfur compounds. Keep cabbage away from Tomato — it competes for nutrients or shares pest pressure.
Frequently Asked Questions
When should I plant cabbage in Arvada, CO?
In Arvada (Zone 6a), start cabbage seeds indoors around February 9–16 and transplant outdoors around March 9–19. The city's average last frost of March 30 is the anchor date — count 7 weeks back for seed starting and 3 weeks back for transplanting.
What zone is Arvada, CO for cabbage growing?
Arvada is USDA Zone 6a. For cabbage, this means a frost-free growing season of roughly 31 weeks running from March 30 to November 1. Cool-season crops like cabbage thrive in this zone with both spring and fall planting windows available.
When is cabbage harvest season in Arvada?
Expect the first cabbage harvest in Arvada around May 8, with harvest continuing through June 17. This is based on 60–100 days from transplant or direct sow. A fall crop planted August 9–19 adds a second harvest around October 8.
How long does it take to grow cabbage in Arvada, CO?
From transplant or direct sow to first harvest, cabbage takes 60–100 days in Arvada's climate. Based on a typical planting date of March 9–19, expect your first harvest around May 8. Arvada's Zone 6a transition-zone climate produces maturity times right in the middle of the stated range.
What soil does cabbage need in Arvada?
Arvada's loam soil is near-ideal for cabbage. Work in 2–3 inches of compost before planting to boost organic matter and nutrient content. Minimal amendment is needed beyond that — loam holds moisture evenly without the drought-crack cycle of clay or the nutrient-loss issues of sandy soil.