When to Plant Sweet Potato in Lothair, Montana (59461)

Location

Lothair, Montana

ZIP Code

59461

USDA Zone

Last Frost

Friday, May 15, 2026

📅 Planting Calendar

Direct Sow Outdoors Friday, May 15, 2026

Pro Tip: Sow Sweet Potato directly outdoors around your last frost date when soil starts to warm.

🌿 Plant Details

Scientific Name Ipomoea batatas

Days to Maturity 100 days

Mature Height 12-18"

Spread 36"

Type Vine

Fruit Size Medium-Large (6-12 oz per root)

☀️ Growing Requirements

☀️

Sun

Full Sun (8+ hours)

💧

Water

Moderate (reduce as harvest approaches)

↔️

Spacing

12" apart

🌱

Planting Depth

4" deep

Seeds typically germinate in 14-21 days

Ready to Plant Sweet Potato in Lothair?

Get your seeds now so they're ready by Friday, May 15, 2026.

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🤝 Good Companions

OkraDillThyme

⚠️ Avoid Planting Near

SquashSunflower

Other Plants for Lothair

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 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 Larkspur 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 Sweet Potato in Zone 4a

Sweet Potato (Ipomoea batatas) is a popular garden vegetable. In Lothair, Montana, which is in USDA Hardiness Zone 4a, you should direct sow seeds around Friday, May 15, 2026.

Your average last frost date is Friday, May 15, 2026. Sweet Potato grows well when direct sown, as it doesn't transplant well or germinates quickly outdoors.