🌱 MyLocalPlanting

When to Plant Onion in Zone 11B

USDA Zone

11B

Cities Covered

14

Avg Last Frost

Friday, January 1, 2027

Plant Type

Indoor Start

📅 Planting Calendar for Zone 11B

Start Seeds Indoors Friday, November 6, 2026
Transplant Outdoors Friday, January 15, 2027

Pro Tip: Start Onion seeds indoors 8 weeks before your last frost date for best results.

🌿 Plant Details

Scientific Name Allium cepa
Days to Maturity 100 days
Sun Requirements Full Sun (6+ hours)
Plant Spacing 4" apart

Cities in Zone 11B

Long Key, Florida Islamorada, Florida Key West, Florida Key West, Florida Summerland Key, Florida Big Pine Key, Florida Key West, Florida Marathon, Florida Key Colony Beach, Florida Marathon Shores, Florida Tavernier, Florida Hana, Hawaii Ocean View, Hawaii Mountain View, Hawaii

Other Plants for Zone 11B

Blackberry Blueberry Raspberry Strawberry Basil Chamomile Chives Cilantro Dill Lavender Lemon Balm Marjoram Mint Oregano Parsley Rosemary Sage Tarragon Thyme Acorn Squash Artichoke Arugula Asparagus Beefsteak Tomato Beet Bell Pepper Bok Choy Broccoli Brussel Sprout Butternut Squash Cabbage Cantaloupe Carrot Cauliflower Cayenne Pepper Celery Cherry Tomato Chili Pepper Collard Green Common Bean Cucumber Eggplant Endive Fennel Garlic Grape Tomato Green Bean Habanero Pepper Head Lettuce Heirloom Tomato Honeydew Melon Jalapeño Pepper Kale Kohlrabi Leaf Lettuce Leek Lima Bean Mustard Okra Parsnip Pea Poblano Pepper Pole Pea Potato Pumpkin Radicchio Radish Rhubarb Roma Tomato Rutabaga Serrano Pepper Shallot Snap Pea Snow Pea Spaghetti Squash Spinach Squash Sweet Corn Sweet Potato Swiss Chard Tomato Turnip Watermelon Zucchini

Browse Other Zones

Zone 1a Zone 1b Zone 2a Zone 2b Zone 3a Zone 3b Zone 4a Zone 4b Zone 5a Zone 5b Zone 6a Zone 6b Zone 7a Zone 7b Zone 8a Zone 8b Zone 9a Zone 9b Zone 10a Zone 10b Zone 11a Zone 12a Zone 12b Zone 13a

Growing Onion in USDA Zone 11B

Onion (Allium cepa) grows well in USDA Hardiness Zone 11B. This zone includes cities like Long Key, Islamorada, Key West and 11 more.

The average last frost date for Zone 11B is around Friday, January 1, 2027. For best results, start your Onion seeds indoors around Friday, November 6, 2026, then transplant outdoors around Friday, January 15, 2027.

Expect to harvest your Onion approximately 100 days after planting.