When to Plant Larkspur in Lake Mc Donald, Montana (59921)

Location

Lake Mc Donald, Montana

ZIP Code

59921

USDA Zone

Last Frost

Sunday, May 10, 2026

📅 Your 2026 Planting Dates

Direct Sow Outdoors

Sunday, April 12, 2026

Based on last frost Sunday, May 10, 2026 · Zone 5a

Pro tip: Sow Larkspur directly outdoors 4 weeks before your last frost date.

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🌿 Plant Details

Scientific Name Consolida ajacis

Days to Maturity 65 days

Mature Height 24-48"

Spread 12"

☀️ Growing Requirements

☀️

Sun

Full Sun to Partial Shade

💧

Water

Moderate (1 inch/week)

↔️

Spacing

9" apart

🌱

Planting Depth

0.25" deep

Seeds typically germinate in 14-21 days

Ready to Plant Larkspur in Lake Mc Donald?

Get your seeds now so they're ready by Sunday, April 12, 2026.

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🤝 Good Companions

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Full Companion Planting Guide for Larkspur

See which plants help Larkspur thrive, which to keep away, and raised bed layout tips →

🛠️ Supplies You'll Need

🌍 Flower Garden Soil ✂️ Pruning Shears 🚿 Watering Can

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🌾 Seed Saving Guide

🟢 Easy

✅ Open-pollinated — seeds grow true to parent

When to Harvest Seed

Allow seed pods to turn brown and dry on the stalk. Harvest before pods split open.

Processing

Crack dry pods to release tiny seeds. Dry in open envelope for 1 week.

Seed Viability

Up to 2 years when stored cool, dark, and dry.

Pro Tip

All parts of larkspur are toxic — wash hands thoroughly after handling seeds. Self-sows readily once established.

🪴

Raised Bed Planting Guides

A 4×8 bed fits 56 plants of Larkspur. See plant counts, spacing grids, and companion pairings for every bed size →

Frequently Asked Questions

When should I plant Larkspur in Lake Mc Donald, Montana? +

In Lake Mc Donald (Zone 5a), direct sow Larkspur outdoors around Sunday, April 12, 2026.

What is the last frost date for Lake Mc Donald, Montana? +

The average last spring frost date for Lake Mc Donald, Montana (ZIP 59921) is around Sunday, May 10, 2026. This is based on NOAA climate normals for USDA Zone 5a.

How long does Larkspur take to grow? +

Larkspur typically matures in about 65 days from direct sowing. In Lake Mc Donald, that means you can expect harvest around Sunday, April 12, 2026 plus 65 days.

Should I start Larkspur indoors or direct sow in Montana? +

Larkspur does best when direct sown outdoors. In Lake Mc Donald, sow directly around Sunday, April 12, 2026.

📚 More Larkspur Planting Guides

🗺️

Larkspur in Montana

Zone-by-zone breakdown · Full state guide

→ 🌡️

Zone 5a Larkspur Guide

All cities in your zone · Avg dates

→

Other Plants for Lake Mc Donald

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 Brussels 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 Onion 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 Sunflower Marigold Zinnia Nasturtium Cosmos Echinacea (Coneflower) Petunia Black-eyed Susan Apple Tree Pear Tree Peach Tree Plum Tree Sweet Cherry Tree Lemon Tree Borage Lemongrass Ginger Stevia Tomatillo Edamame Fava Bean Mâche Mizuna Sorrel Shishito Pepper Banana Pepper Watermelon Radish Napa Cabbage Popcorn Broccoli Raab Catnip Valerian Lemon Verbena Bee Balm Anise Lovage Chervil Summer Savory Dahlia Snapdragon Pansy Sweet Pea Morning Glory Hollyhock Bachelor Button Columbine Impatiens Salvia (Annual) Sweet Alyssum Celosia Lupine Verbena Elderberry Grape Vine Red Currant Gooseberry Serviceberry Fig Tree Avocado Tree Persimmon Tree Olive Tree

Growing Larkspur in Zone 5a

Larkspur (Consolida ajacis) is a popular garden vegetable. In Lake Mc Donald, Montana, which is in USDA Hardiness Zone 5a, you should direct sow seeds around Sunday, April 12, 2026.

Your average last frost date is Sunday, May 10, 2026. Larkspur grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.