Growing Milkweed from seed:

• Milkweed is a vital plant for monarch butterflies, providing both food and shelter for their caterpillars. If you want to help support the monarch population, growing milkweed from seed is a great way to do it.

Quick Guide

Start Indoors (recommended):

• Cold Stratification: 3-6 weeks (approximately 30 days)

• Timing: sow indoors 4-6 weeks before planting out

• Seed Depth: 1/4"

• Germination time: 10-15 days

• Transplant out: when seedlings are ~3 inches tall

Plant Specifications

Light Preference

Plant Height

Plant Spacing

Hardiness

Full Sun

30-60"

12-18"

Perennial

Step-by-Step Instructions - Starting Seeds Indoors

Collect Supplies:

• Seeds

• Seed starting trays or pots

• Seed starting mix (sterile)

• Labels and a marker

• Plastic wrap or a humidity dome

• Spray bottle or watering can with a fine nozzle

• Grow lights or a sunny windowsill

  Timing

  • Cold Stratification: Place milkweed seeds in a damp paper towel inside a ziplock bag and store them in your refrigerator for 3–6 weeks (approximately 30 days). Choose a safe spot in the fridge where they won't be disturbed; taping the bag to the underside of a refrigerator shelf works well.

  • When to Start: Sow seeds indoors about 4 - 6 weeks befoe planting out.

  Preparation

  • Clean Containers: Sterilize your seed starting trays or pots to prevent disease.

  • Moisten Seed Mix: Slightly moisten your seed starting mix so it's damp but not soggy.

  Planting Seeds

  • Fill Trays: Fill each cell in the seed tray with the moist seed starting mix.

  • Sow Seeds: Place 1-2 seeds in each cell.

  • Label Trays: Label each tray or pot with the variety and the planting date.

  Germination

  • Cover Seeds: Cover seeds with 1/4" of soil.

  • Moisten Surface: Use a spray bottle to mist the top of the soil.

  • Create Humidity: Cover the seed trays with plastic wrap or a humidity dome to maintain moisture.

  • Warmth: Place the trays in a warm location (70-75°F or 21-24°C). A heat mat can help.

  Light and Watering

  • Lighting: Once the seeds germinate (about 10-15 days), remove the cover and place the seedlings under grow lights or in a sunny windowsill. Provide 12-16 hours of light per day.

  • Watering: Keep the soil moist but not waterlogged. Water from the bottom if possible to prevent damping-off disease.

  Take Care of Seedlings

  • Thinning: Once seedlings have two sets of true leaves, thin them to one plant per cell or pot.

  • Hardening Off: About a week before transplanting outdoors, start to harden off your seedlings by gradually exposing them to outdoor conditions for increasing time periods each day.

  Transplanting Outdoors

  • Timing: Transplant the seedlings outdoors when they are about 3 inches tall.

  • Soil Preparation: Choose a sunny spot with well-draining soil. Amend with compost if needed.

  • Planting: Plant seedlings 12-18 inches apart.

  • Watering: Water thoroughly after planting.